esa-sceva/satcom-chunk-collection huggingface dataset:
# Research Progress Regarding the Precision of Dosing and Distribution Devices for Fertilizers
## 2 Current Status of Research on Precision Fertilizer Dischargers
### Research Status of Spiral Fertilizer Dischargers
The research above primarily focused on parameters such as pitch, number of heads, inner and outer diameters, length, gap, center distance (for double-spiral blade), blade height, blade thickness, rotation speed of the spiral blades, as well as the length and angle of the fertilizer discharge port. These were investigated through discrete element simulation, bench tests, field trials, and other research methodologies. The aim was to enhance the stability and uniformity of fertilizer discharge, meeting the requirements for precise fertilization dosing. This research provides a comprehensive foundation for the design and optimization of spiral fertilizer dischargers and offers valuable technical support for agricultural production.
# Data and Knowledge-Driven Bridge Digital Twin Modeling for Smart Operation and Maintenance
## 4 Spatiotemporal Data Collection and Processing for Bridge Digital Twin
### Expert Knowledge
#### 4.4.1 Acquiring Expert Knowledge  
Unlike traditional data, expert knowledge is mainly acquired through expert interviews, expert workshops, national standards, and historical case analyses. Expert interviews are a direct way to acquire expert knowledge.  
Through structured interviews, knowledge of specific damage types such as bridge cracks, corrosion, and deformations can be systematically collected from experts. By systematically recording the experts' evaluation criteria and qualitative judgments for different types of damage, this information forms a key foundation for the expert knowledge base.  
Expert workshops bring together multiple experts in bridge engineering to discuss particular types of bridge damage. Through discussions, a consensus is reached regarding the evaluation and assessment of the damage types. Expert workshops primarily focus on complex or controversial issues in order to form a systematic framework for damage evaluation. National standards and industry regulations are authoritative sources of expert knowledge. The standards published by the government and industry detail the methods for monitoring and assessing bridge damage under various circumstances. By carefully analyzing the content of these standards, key indicators and criteria related to bridge damage are extracted. Standards represent the primary source of data informing expert knowledge. Historical case analysis provides expert knowledge that has been validated through real-world practice. By analyzing successful cases of bridge monitoring and maintenance, specific and effective measures can be summarized. Furthermore, through historical case analysis, the development patterns and characteristics of similar types of damage, such as regions where cracks tend to concentrate or deformation trends, are identified. Historical cases provide valuable empirical insights and further enhance expert knowledge.
## 1 Introduction
In 2009, [PERSON] [12] proposed a linear BSS method based on the Ant Colony Optimization (ACO) algorithm. In 2016, [PERSON] et al. [13] proposed a firefly optimization algorithm based on a new step size adjustment rule and applied it to the BSS problem. In 2018, [PERSON] et al. [14] optimized the signal's kurtosis using the whale optimization technique with adaptive weights, which still provided good separation performance at low signal-to-noise ratios. [PERSON] presented a nature-inspired metaheuristic called the Marine Predators Algorithm (MPA) and its application in engineering in 2020 [15]. [PERSON] proposed the slime mold algorithm, and [PERSON] introduced a new method called the Mayfly Algorithm (MA) to solve optimization problems in the same year [16; 17]. A BSS approach based on the genetic lion swarm optimization algorithm was proposed by [PERSON] et al. in 2021 [18], which effectively applied the algorithm to the blind separation of image signals while increasing the accuracy of the algorithm. This article proposes an improved BCA algorithm based on BAS-BCA to solve the problems of slow convergence speed and unstable precision in the BCA algorithm. Without any prior knowledge, this algorithm can extract and separate independent and dependent source signals from mixed signals. The BAS algorithm avoids entering local optima during the iteration process by providing a step decay factor. The objective function of the BCA algorithm is optimized using the improved BAS algorithm, enhancing the efficiency and precision of the method. Simulation experiments prove that this algorithm not only has stronger universality but also has faster convergence speed and more stable precision than traditional blind source separation algorithms and BCA algorithms. To summarize, the major contributions of this paper are given as follows:1. An improved BCA algorithm based on the Beetle Antennae Search (BAS) algorithm is proposed to address the shortcomings of conventional blind source separation algorithms. 2. A step decay factor is introduced to the BAS algorithm, which avoids entering local optima during the iteration process. 3. Simulation results show that the BAS-BCA algorithm successfully separates the dependent and independent source signals. This algorithm not only has stronger universality but also has faster convergence speed and more stable precision than traditional blind source separation algorithms and BCA algorithms. The rest of the paper is organized as follows: Section 2 introduces the BSS model and the basic BCA algorithm; Section 3 introduces the improved BAS algorithm and the proposed BAS-BCA algorithm; the performance of this method was demonstrated via simulation analysis in Section 4; The conclusion is shown in Section 5.
# Impacts of Land-Use Change from Primary Forest to Farmland on the Storage of Soil Organic Carbon
## 4 Discussion
### Effects of Continuous Cropping and Fallow on SOC Stocks in Cultivated Land  
In order to evaluate the impact of increasing CO\({}_{2}\) concentration in the growing environment of crops due to continuous cropping on SOC dynamics, [PERSON] et al. (2016) [35] conducted an experiment in Hyderabad, India. Using an open top chamber (OTC) experimental design, they measured the unstable carbon, stable carbon, total carbon, instability index (LI), carbon pool index (CPI), and carbon management index (cmI) of sorghum, pearl millet, sunflower, peanut, cowpea, black bean, and castor bean in three environmental conditions (CO\({}_{2}\) levels were 380 ppm, 550 ppm, and 700 ppm, respectively) after five years (2005-2010) and after planting these crops in open land and in a fallow plot at the depths of 0-0.2 m, 0.2-0.4 m, and 0.4-0.6 m. The results showed that, compared with the fallow condition, the highly unstable carbon, the unstable carbon, and the stable organic carbon components in the depth range of 0-0.4 m increased with the increase in CO\({}_{2}\) level. However, the increases in unstable carbon, stable carbon, and total carbon components at the same depth peaked at the CO\({}_{2}\) level of 550 ppm and decreased until 700 ppm. LI, CPI, and cmI are sensitive indicators of SOC changes due to land use change and management practices. According to [PERSON] et al. (2008) [36], cmI values greater than 100 and less than 100 indicate positive and negative impacts of land use and management practices on SOC changes, respectively, while low CPI values indicate SOC loss. Such experimental results mean that excessive environmental CO\({}_{2}\) levels have a negative impact on soil quality and soil carbon sequestration capacity. After 30 to 50 years of cultivation, SOC loss in the surface soil (0-0.20 m) is as high as 50%, and SOC loss in the upper 1 m soil is about 30%. Such large and relatively rapid changes in soil organic carbon caused by land cultivation indicate that appropriate agricultural management can improve soil carbon sequestration capacity, thereby reversing the negative impact of crop cultivation on soil organic carbon pool. Crop cultivation reduces the size of total carbon pool and microbial carbon pool and affects soil fauna but increases metabolic CO\({}_{2}\). Management measures to improve SOC reserves and organic matter accumulation include returning farmland to forest, nutrition management, irrigation management, grazing management, rational use of cover crops and grasses, and the introduction of beneficial organisms to soil such as earthworms.
# Combination of Chemo- and Biocatalysis: Conversion of Biomethane to Methanol and Formic Acid
## 3 Results and Discussion
### Cascade Combining Chemo- and Biocatalysis  
After the optimization of the separate processes both were combined in the chemo-/biocatalytic oxidation cascade. The used set-up is presented in Scheme 2. The feed was composed of CH\({}_{4}\), CO\({}_{2}\) and O\({}_{2}\) in the ratio of 9:9:1.  
In the first mode, formaldehyde was first introduced into the buffer solution by absorption in the absence of free FDM. The formaldehyde feed (chemocatalytic product gas stream) was switched off after 160 min and 176 mg free FDM containing raw extract dissolved in 10 mL buffer was added to the stirred vessel. The enrichment of the formaldehyde and the formation of methanol after addition of the FDM are shown in Figure 4a. After 30 min the reaction was completed. Nearly no formaldehyde could be detected, and the methanol concentration was about 0.2 g\(\cdot\)L\({}^{-1}\). The concentration of formic acid increases in the same way and the initial enzyme activity in this experiment was 17,900 nmol\(\cdot\)mg\({}^{-1}\cdot\)min\({}^{-1}\) for both components.  
In the second mode, the cascade was operated continuously since the use of immobilized enzymes enables a reaction during absorption. Moreover, product removal is simplified reducing the problems caused by product inhibition, which might be interesting for possible applications. Figure 4b shows the enrichment of formaldehyde in the tank as consequence of ongoing feeding from chemocatalytic methane conversion. The constant gassing caused a saturation of the buffer solution with carbon dioxide and methane, so that bubbles entered the membrane inlet of the mass spectrometer and led to the noise of the measurement signal. In parallel, the formaldehyde in the buffer solution within the stirrer tank is simultaneously converted by the immobilized enzyme to methanol and formic acid. After an induction period of about 30 min, the onset of the reaction was observed. The methanol concentration increased linearly up to 20 mg\(\cdot\)L\({}^{-1}\) and the formaldehyde concentration reached a maximum of 0.3 g\(\cdot\)L\({}^{-1}\) at the end of the experiment. The overall productivity was 30 nmol\(\cdot\)mg\({}^{-1}\cdot\)min\({}^{-1}\) for both components.  
Figure 3: Product inhibition of the free FDM by different concentrations of methanol (**a**) and formic acid (**b**).  
Two points speak clearly against an exact implementation: (i) the lower productivity compared to industrial methanol production and (ii) ongoing product enrichment. Hence, it can be stated that the aforementioned approach only demonstrates the concept and a direct transfer to industry would be impractical. We suggest that productivity could be improved by site-selective immobilization. Moreover, in order to retain the protein structure and high activity of the FDM immobilization in cavities using porous polymers or glasses could be utilized. Furthermore, the inhibition of FDM by formed products could be solved by in situ product removal as it will be shown on idealized mixtures in the following.
# A Survey of Methods and Technologies for Congestion Estimation Based on Multisource Data Fusion
## 4 Data Collection Technologies
The discovered traffic co-congestion patterns are then used to detect anomalies in the arterial network and better estimate traffic conditions of a large arterial network. [PERSON] et al. [72] developed a real time fusion-based system using GNSS probe taxi vehicle data and loop data from the Sydney Coordinated Adaptive Traffic System (SCATS). In review [73], authors separated multisource data on the traditional research data (survey data, bank notes, call detail records), and popular urban data (GNSS data, public transport data, social media check-in data) used for modeling and predicting human-mobility patterns. [PERSON] et al. in [74] used three different data sources: GNSS data obtained from buses, inductive loop data, and mobile phone network data, while automatic number plate recognition data were used as a ground truth. For the traffic speed prediction in [75], data was obtained from inductive loop devices in combination with weather data. Novel research [64] proposed a combined method for estimating traffic conditions fast and accurately by using connected vehicles combined with stationary detectors. [PERSON] et al. [76] proposed a more accurate visualization of traffic conditions using specific elements of Transport System models zones and graphs. Procedure included DF of GNSS and traditional survey data. In [77], authors develop a framework for traffic state estimation using data collected from point detectors (loops, cameras, and radar) and probe data (GNSS and Bluetooth). The framework can filter, fuse, and process data from various sources in real time, providing a reliable Advanced Traveler Information Service (ATIS). The authors in [78] developed a new convex optimization framework for route flow estimation problem using a fusion approach for loop detectors and cellular signal traces. Most of the authors used GNSS probe data and inductive loop data for DF. An inductive loop is a well-known technology, and in combination with GNSS probe data, it can overcome mutual shortcomings. Most authors use GNSS probe data because of their large spatial coverage and potential for real-time traffic state estimation.
## 5 Conclusions  
The VR gaming solution for rehabilitation after musculoskeletal injuries presented in this study showed a high perceived usability of the system, greater intrinsic motivation to perform the rehabilitation exercises, a high level of immersion, and a good experience in the VR gaming environment. Therefore, this technological solution for musculoskeletal injury rehabilitation based on VR games can be adopted as a novel rehabilitation tool in elite or amateur soccer. Finally, the variation in the rated perceived exertion and heart rate when participants exercise the entire rehabilitation session using an immersive virtual reality system agreed with the intensity progression requested throughout the three training session phases. The efficacy of this immersive virtual reality rehabilitation system on soccer musculoskeletal injury might be tested with a more extended intervention program.  
Conceptualization, E.R.G., P.C., F.G. and B.R.G.; Methodology, C.S.F., L.M.R., F.T., F.M. and C.F.; Validation, A.I., B.R.G. and P.C.; Formal analysis, E.R.G. and B.R.G.; Investigation, C.S.F., L.M.R., F.T., F.M. and C.F.; Resources, E.R.G., P.C., F.G. and B.R.G., Writing--original draft preparation, E.R.G., P.C. and B.R.G.; Writing--review and editing, C.S.F., L.M.R., F.M., C.F., F.T. and A.I.; Visualization, P.C. and A.I.; Project administration, E.R.G., P.C., F.G. and B.R.G.; Funding acquisition, E.R.G., P.C., F.G., A.I. and B.R.G. All authors have read and agreed to the published version of the manuscript.  
This study was framed in the Maritime Training Lab Project. The project received funding under application no. M1420-01-0247-FEDER-000033 in the System of Incentives for the Production of Scientific and Technological Knowledge in the Autonomous Region of Madeira--PROCiencia 2020. C.F., F.M., and E.R.G. acknowledge support from LARSyS--the Portuguese national funding agency for science, research, and technology (FCT) plurianual funding 2020-2023 (Reference: UIDB/50009/2020). This work was further supported by the Swiss National Centre of Competence in Research LIVES, \"Overcoming Vulnerability: Life Course Perspectives\", granted by the Swiss National Science Foundation (Grant Number: 51 NF40-185901). A.I. acknowledges support from the Swiss National Science Foundation (Grant Number: 10001C_189407).  
This study was conducted according to the guidelines of the Declaration of Helsinki, was approved by the Ethics Committee of the Faculty of Human Kinetics (CEIFMH N\({}^{\circ}\)34/2021), and followed the ethical standards of the Declaration of Helsinki for Medical Research in Humans (2013) and the Oviedo Convention (1997).  
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.  
The data presented in this study are available upon request from the corresponding author.  
The authors would like to thank all participants and team staff for participating in this study.  
The authors declare no conflict of interest.
# Theoretical Study of the Wear of a Reduced-Diameter Wheel for Freight Wagons, Based on Its Diameter
## 3 Results  
After running the algorithm, the diameter versus mileage curves are obtained, with the diameter measured in millimeters (mm) and distance traveled in kilometers (km). Detailed results are discussed in Section 4, but here are some key figures:  
1. The 920-mm wheels can travel up to 124,275 km before their diameter reduces to 840 mm. These wheels lose 2 mm in diameter with each reprofiling cycle, at which point they are replaced for safety and operational reasons.
2. The 680-mm wheels are able to travel for 75,648 km before reaching their minimum allowed diameter of 630 mm. In practice, this is the point at which the wheels are retired. However, if the wear and reprofiling cycles are extended as though the minimum diameter could be 600 mm (similar to the difference between 680 and 600 being analogous to the difference between 920 and 840), the wheels would theoretically last 118,683 km.
3. The 355-mm wheels are capable of traveling 26,983 km before their diameter reaches the minimum allowed size of 335 mm. This is the practical end of their service life. If wear and reproffiling cycles were extended as if the final diameter could be 275 mm (with the difference being similar to that of the 920 to 840 scenario), the wheels would theoretically travel 101,433 km.  
Additionally, the worn wheel profile is represented by mapping the wear depths onto the zones of a real wheel profile. This wear is determined after a randomly chosen distance traveled, using coordinates for the vertical position (\(z_{p,f}\)) and horizontal position (\(y_{p,f}\)). The worn profiles indicate that flange wear is much more significant compared to the minimal tread wear. This is expected due to the aggressive nature of flange-rail contact and the prevalence of tight curves on the railway line. The algorithm shows that in most flange-rail contacts, rolling contact fatigue (RCF) occurs due to high normal pressures and tangential stresses.  
Figure 16 presents the diameter versus mileage curves and the worn wheel profile, with the latter shown in the lower right corner. The first plot demonstrates that wheels start with a nominal diameter of 920 mm at the tread. Upon reaching the wear depth limit (1 mm in radius or 2 mm in diameter), the wheel is sent for lathing. This process begins with a nearly new diameter of 920 mm at the tread and ends with a diameter of 917 mm. Consequently, 3 mm of material is removed (1.5 mm per side when viewed in cross-section). The wheel then exits the workshop with a diameter of 917 mm, wears down to 915 mm, and is reprofiled from 917 mm to 914 mm, and so forth:
## 4 Discussion and Application Field of the Model
[3]). It is important to highlight that the present analytical model is only applicable to represent travelling fire scenarios. It does not allow to automatically transition to flashover and is not appropriate to represent fully developed compartment fires. In the frame of the \"TRAFIR\" project ([PERSON] et al. [31]), CFD parametric analyses were performed to better understand in which conditions a travelling fire would develop; applying this analytical model amounts to consider that a travelling fire is developping. [PERSON] et al. [32] proposed a three modes classification of the fire dynamics based on the ratio of flame spread velocity and burnout front velocity: \"fully developed\", \"growing\" and \"travelling\". [PERSON] et al. [33] precise heat fluxes criteria allowing to distinguish between them; the \"travelling\" mode occurs when enclosure heat losses are important enough such that the pre-heating by the external heat flux ahead of the flame front is minimal. Several modifications can therefore be brought to improve the proposed analytical procedure. Some of these may be deemed as possible for an analytical approach (for example: multi directional fire spread), but others may be dealt with only through the use of numerical tools (for example: automatic transition to flashover and consideration of the exact location and evolution of the openings). In both cases, the authors would like to encourage further work on this topic to improve the proposed procedure. The authors would like to point out that this methodology is not aimed at performing detailed analysis of the local fire dynamics; it is aimed at evaluating the structural response (i.e., heating of the structural elements, followed by a mechanical analysis) in a compartment subjected to travelling fire.
## 8 Multi-Segmental Channel Estimation  
In this section, we present the MSCE technique to estimate time-varying channels and discuss the pilot symbol selection in each iteration. Additionally, the MSCE can be terminated in an early iteration by comparing with previous estimates.  
Figure 4: The uncoded bit error rate analysis of the system with the presence of the residual inter-carrier interference (ICI) outside the band (Q = 2,4,6). \(N_{s}=128,f_{d}T_{\text{OFDM}}=0.65\), \(L=~{}8\).