esa-sceva/satcom-chunk-collection huggingface dataset:
# A Real-Time On-Orbit Signal Tracking Algorithm for GNSS Surface Observations
## 5 Results: Algorithm Verification Using On-Orbit Data
### Open Loop Tracker Code Phase Predictions
The reflection for PRN 21 passes onto land at approximately second 43 (while the PRN 26 reflection is over an ocean for the whole duration). At second 43, the PRN tracking error using the ocean WGS84 ellipsoid reference starts to increase. However, the red trace shows the improvement in delay tracking performance after the land transition when the land surface elevation is included in the estimate of the specular reflection point in Equation (8).
# Review of Task-Scheduling Methods for Heterogeneous Chips
## 3 Research Status of the Task-Scheduling Framework
### Distributed Scheduling Framework  
Compared to centralized scheduling, the distributed scheduling framework of heterogeneous chips has decentralized scheduling responsibilities into multiple scheduling components, which are usually distributed on different physical or logical nodes [7; 8]. Each node or component is responsible for the scheduling of a portion of the resources, allowing the system to process scheduling decisions in parallel at multiple levels, significantly improving the scalability and fault tolerance of the system. As shown in Figure 5b, the Intel Loihi 2 neuromorphic chip [18] is based on a distributed task-scheduling framework and uses the asynchronous pulse routing protocol to achieve autonomous task negotiation and dynamic load balancing among 128 neural core clusters and supports sparse event-driven computing of spiking neural networks. Moreover, distributed scheduling has local decision-making power to better adapt to local changes in the system state.  
However, the framework has some shortcomings. First, the design and implementation of a distributed scheduling framework are usually accompanied by high communication overhead, especially when frequent synchronization and coordination between nodes are required. This may result in decreased overall system performance. Second, since each node makes independent decisions, maintaining the consistency and fairness of the scheduling method on a global scale is a challenge, especially in resource competition or fierce competition. In addition, when a node failure occurs, although the distributed framework has some fault tolerance, the fault propagation and recovery mechanism may still affect the stability of the system and the task completion time. Due to the dependencies of complex tasks in the heterogeneous chip environment, distributed scheduling makes it difficult to optimize the global execution efficiency of tasks comprehensively, and suboptimization problems can easily occur.
# Promoting Urban Farming for Creating Sustainable Cities in Nepal
## 5 Empirical Analysis
### Estimated Urban Food Production, and Contributions to Household Income  
We can estimate the approximate average that can be used for urban agriculture in Nepal by making some simple assumptions, as follows:  
1. The total number of dwelling units (DU) 3.96. Section 5.2 c.
2. Typical size of dwelling units = 90-150 square meters (average 120 square meters); 30 m\({}^{2}\) can be assigned to a dwelling unit (DU).
3. Area available for urban farming on flat roofs (assuming half of the buildings have flat roofs) and that, on average, buildings are two stories and have balconies (typically 5 m\({}^{2}\)/DU) and front/back/side yards (typically 5 m\({}^{2}\)/DU) = 30 + 5 + 5 = 40 m\({}^{2}\).
4. Assuming half of the available area is used for urban farming, each DU can use 20 m\({}^{2}\) for farming.
5. Referring to Table 4 in Section 4, productivity per square meter of 3 kg of mixed typical vegetables (potato, beans, cabbage, fruits, etc.), the total production is 60 kg/growth cycle (3 times a year) = 778 kg/yr./household (an average household consists of 4.32 persons).
6. The production per household = 778 kg/yr. It will be monetarily equivalent to approximately Rs 46,680/yr./household, assuming the average price of the typical vegetables to be Rs 60/kg in 2022. The prices are based on the price list published in major newspapers in Kathmandu. According to the 2022 exchange rate, this is approximately equal to USD 360 per year).
7. Annual food expenditure per household in Nepal is Rs 144,330 (45% of 322,730)/yr.
8. (USD 1206 in 2017) [(49)].
9. Assuming a similar expenditure in 2022 and assuming any growth in expenditure and the rise of the dollar against Nepali Rupees can wash each other out, urban agriculture can provide 27% of a household's food expenditure.
10. With the above assumptions, we can conservatively assume that urban agriculture can save a household 25% of its food expenditure.
## 2 Frequencies and Mode Shapes of the Double-Beam System
### Mathematical Formulation
\begin{array}{c}\omega_{n}^{(1)}\\ =\frac{\widetilde{\omega}_{2,\theta}}{\sqrt{2}}\sqrt{\left(1+\frac{s_{\mathrm{ k}}}{s_{\mathrm{m}}}\right)+\left(1+\frac{1}{s_{\mathrm{m}}}\right)\frac{s_{ \mathrm{e}}}{\left(r^{(n)}l\right)^{4}}-\sqrt{\left[\left(1-\frac{s_{\mathrm{ k}}}{s_{\mathrm{m}}}\right)+\left(1-\frac{1}{s_{\mathrm{m}}}\right)\frac{s_{ \mathrm{e}}}{\left(r^{(n)}l\right)^{4}}\right]^{2}+\frac{4s_{\mathrm{e}}^{2}} {s_{\mathrm{m}}\left(r^{(n)}l\right)^{8}}}}\\ \omega_{n}^{(2)}\\ =\frac{\widetilde{\omega}_{2,\theta}}{\sqrt{2}}\sqrt{\left(1+\frac{s_{ \mathrm{k}}}{s_{\mathrm{m}}}\right)+\left(1+\frac{1}{s_{\mathrm{m}}}\right) \frac{s_{\mathrm{e}}}{\left(r^{(n)}l\right)^{4}}+\sqrt{\left[\left(1-\frac{s_{ \mathrm{k}}}{s_{\mathrm{m}}}\right)+\left(1-\frac{1}{s_{\mathrm{m}}}\right) \frac{s_{\mathrm{e}}}{\left(r^{(n)}l\right)^{4}}\right]^{2}+\frac{4s_{\mathrm{ e}}^{2}}{s_{\mathrm{m}}\left(r^{(n)}l\right)^{8}}}}\end{array}  \tag{9}\]  
where \(s_{\mathrm{e}}\) is the contact stiffness ratio which is a dimensionless stiffness ratio defined as follows:  
\[s_{\mathrm{e}}=\frac{k_{\mathrm{e}}l^{4}}{E_{2}I_{2}} \tag{10}\]  
and  
\[\widetilde{\omega}_{2,n}=\left(r^{(n)}\right)^{2}\sqrt{\frac{E_{2}I_{2}}{\rho_ {2}A_{2}}} \tag{11}\]  
\(r^{(n)}l\) represents the \(n\)th wavenumber of the double-beam system and it is a constant depending on the boundary conditions of the double-beam system. It will be shown below that the wavenumbers of the double-beam systems are the same as those for a single beam if the boundary conditions of the primary beam are the same as the secondary beam (symmetric boundary conditions). Therefore, Equation (11) also represents the \(n\)th natural frequency of a single secondary beam. It can be seen from Equation (9) that two sub-modes of the double-beam system are corresponding to one wavenumber of the double-beam system. The order of the wavenumber of the double-beam system is defined as the basic mode number in the following context. The following relationship can be obtained from Equation (8)  
\[\left\{ \begin{array}{l}r_{2}=-r_{1},\ r_{3}=r_{1}i,\ r_{4}=-r_{1}i\\ r_{6}=-r_{5},\ r_{7}=r_{5}i,\ r_{8}=-r_{5}i\end{array} \right. \tag{12}\]  
Substituting Equation (12) into Equation (7) results in  
\[\varphi_{2}(x)=C_{1}e^{r_{1}x}+C_{2}e^{-r_{1}x}+C_{3}e^{ir_{1}x}+C_{4}e^{-ir_{ 1}x}+C_{5}e^{r_{5}x}+C_{6}e^{-r_{5}x}+C_{7}e^{ir_{5}x}+C_{8}e^{-ir_{5}x} \tag{13}\]
## 2 Results
### In Planta, RNAi of Ab-far-1 Impairs the Parasitism and Pathogenicity of RWTNs  
RNAi sense and antisense fragments of 130-372 bp within _Ab-far-1_ were constructed into the pFGC5941 vector. Subsequently, the pFGC5941-355: _Ab-far-1_ hairpin dsRNA vector was obtained (Figure S2). Two single-copy _Ab-far-1_ RNAi _A. thaliana_ T3 generation lines (RNAi5 and RNAi8) were obtained through transformation and screening (Figure S3) and  
Figure 5: Investigation of _Aphelenchoides besseyi_ parasitism on Ab-FAR-1 Asp overexpressing (OE) and _Ab-far-1_ silencing (RNAi) _Arabidopsis thaliana_. (**a**) Symptoms of damage in various _A. thaliana_ lines. (**b**) The symptom severity in various _A. thaliana_ lines. (**c**) The total numbers of nematodes were counted in various _A. thaliana_ lines. These data of Ab-FAR-1 Asp overexpressing line 1# (FOE1) and 3# (FOE3), _Ab-far-1_ silencing line 5# (RNAi5) and 8# (RNAi8), empty vector transgenic line (EV) and their wild types (WT) were recorded at 21 days post inoculation (dpi) with _A. besseyi_. Values are indicated as the means \(\pm\) SE, \(n\) = 15. (**d**) The _Ab-far-1_ gene was silenced in _A. besseyi_ collected from _A. thaliana_ RNAi lines. The _Ab-18S_ gene was used as an internal reference gene. The expression levels of _Ab-ubc_ from _A. besseyi_ were used to determine the specificity of the _Ab-far-1_-targeting RNAi. Values are means \(\pm\) SE, \(n\) = 3. Asterisks denote significant differences (* \(p\) \(<\) 0.05, ** \(p\) \(<\) 0.01; _t_-test). There were three independent biological replicates.  
used for the RWTN infection assays. Two RNAi lines and WT plants were inoculated with RWTNs for 21 days, and the symptom severity was monitored. Results indicated that the symptom severity of the RNAi5 and RNAi8 lines was significantly lower (_p_ < 0.05) than that of the WT (Figure 5a,b). The nematode populations on RNAi5 and RNAi8 were 1344 \(\pm\) 173 and 1489 \(\pm\) 130, respectively, which were significantly lower (_p_ < 0.05) than those on WT (3063 \(\pm\) 199) (Figure 5c). Real-time quantitative PCR results showed that the expression level of the _Ab-far-1_ gene was significantly decreased by 86.65% and 87.57% upon infection of the RNAi5 and RNAi8 lines, respectively, compared with nematodes from WT (_p_ < 0.05) (Figure 5d). The expression of the control gene _Ab-ubc_ was not significantly different among the treatments. These results indicate that both RNAi lines specifically silenced the _Ab-far-1_ gene, resulting in a decrease in the parasitism and pathogenicity of RWTNs.
# Research on Seeding Performance of Self-Propelled Industrial Hemp Seeder
## 4 Test and Verification of Seed Metering Device
### Single Factor Test Results
#### 4.4.2 Effect of Hole Diameter on Each Index  
Figure 11 shows the single factor test results of the effect of hole diameter on seeding performance. The results showed that when the rotational speed of the metering wheel was 90 mm and the depth of the hole was 6.5 mm, the variation coefficient of seeding uniformity decreased first and then increased with the increase in the hole diameter. The seed metering quantity increased with the increase in the rotational speed of the metering wheel. The seed rate of 10-12 mm hole diameter was 150.95-177.34 g/min, which met the seed rate index of 150.10-178.29 g/min.  
Figure 10: Relationship curve between the rotational speed of the seeding shaft and each index.  
The reason is that the hole diameter is too small, and the seeds are filled with'vertical posture' in the filling process. The probability of incomplete seed filling into the hole increases, resulting in a decrease in the number of seed filling and uneven distribution of seeds. If the diameter of the hole is too large, the seed is easier to fill the hole and the seed metering capacity increases. Still, some seeds with significant differences in particle size make the filling number of a single hole unstable and affect the metering performance. Therefore, the hole diameter has a significant impact on the seeding effect.
## Conclusions  
Sentinel-2 data time series using a parcel-based quadratic SVM classification provided a successful crop identification product, reaching an overall accuracy higher than 0.87 Cohen's kappa, for the lowest level of the crop nomenclature hierarchy. RF classification provided comparable results for the family and season of cultivation nomenclature levels, while it underperformed for the crop type level. Also, Landsat-8 OLI imagery, of lower spatial resolution, resulted in inferior performance, validating the argument of Sentinel 2's dominance in smallholding agriculture mapping.  
Accurate crop classification enables the monitoring of the CAP and allows for effective and efficient decision making on farmer compliance. The proposed methods were designed appropriately to be geographically independent and potentially scalable from the extent of a small region to national or even continental scales. In the same fashion, input data are deliberately kept least and freely available in order to achieve maximum transferability and ease of data retrieval.  
The following are available online at [[http://www.mdpi.com/2072-4292/10/6/911/s1](http://www.mdpi.com/2072-4292/10/6/911/s1)]([http://www.mdpi.com/2072-4292/10/6/911/s1](http://www.mdpi.com/2072-4292/10/6/911/s1)).  
[PERSON], [PERSON] and [PERSON] conceived and designed the methodology; [PERSON] and [PERSON] implemented the scheme and performed all relevant experiments; [PERSON], [PERSON] and [PERSON] collected and provided the input data (LPIS, farmer declarations, validation dataset) and critically analyzed the results; [PERSON] wrote the paper.  
Authors acknowledge the Copernicus Open Access Hub ([[https://scihub.copernicus.eu/](https://scihub.copernicus.eu/)]([https://scihub.copernicus.eu/](https://scihub.copernicus.eu/))), Hellenic National Sentinel Data Mirror Site ([[https://sentinels.space.noa.gr/](https://sentinels.space.noa.gr/)]([https://sentinels.space.noa.gr/](https://sentinels.space.noa.gr/))) and the USGS for providing free access to Sentinel-2 MSI and Landsat-8 OLI images, correspondingly. We are also grateful to INTIA for supplying the farmers' declarations, LPIS data and phenology timeline. Finally, the authors would like to acknowledge the contribution of the section editor in chief [PERSON] and an anonymous reviewer, whose comments and suggestions were instrumental in strengthening the arguments of the study.  
The authors declare no conflict of interest.
## 2 Numerical Simulation of CSG Dam upon Overburden
### Project Overview and Establishment of Finite Element Model
#### 2.1.2 Model Size and Division of Finite Element Mesh  
The cemented sand gravel dam in a certain design phase is located on a sand gravel soil overburden. The dam body upon overburden is composed of CSG materials, with a height of 41.5 m and a dam crest width of 6 m. The dam body is divided into two stages at an elevation of 8.5 m. The upstream slope ratio of the first stage is 1:1.235, and the downstream slope ratio is 1:1.182. The upstream slope ratio of the second stage is 1:0.5, and the downstream slope ratio is 1:0.65.  
Using the direction of the river flow as the positive direction of the \(X\)-axis, the upward direction perpendicular to the river flow as the positive direction of the \(Y\)-axis, and the outward direction perpendicular to the paper surface as the positive direction of the \(Z\)-axis, ANSYS is used to establish a finite element model of the CSG dam upon overburden. The specific dimensions are shown in Figure 2. The model takes a unit thickness of 1 m in the \(Z\)-axis direction, and full constraints are added to the lower boundary of the model. We apply normal constraints to the two interfaces perpendicular to the \(X\)-axis on the dam foundation, and also apply normal constraints on the two cross-sections perpendicular to the \(Z\)-axis, forming a three-dimensional model of the dam with unit length. The model adopts mapping mesh division, and 4882 mesh elements are divided, with a total of 5002 nodes. The diagram is shown in Figure 3.  
Figure 2: Section of dam (unit: m).
# A Study on Design Requirement Development and Satisfaction for Future Virtual World Systems
## 3 New Requirement Space Development
### Persistency  
The persistency requirement includes state persistency and content persistency. State persistency requires that when a user leaves an application, his/her application state is well-kept for the next-time retrieval and play [76]. State data normally has a small size but could be frequently updated. Thus, data read/write efficiency is the main concern. [77] found that some states only require approximate consistency between write and read (e.g., avatar position), while others require exact consistency (e.g., user inventory). Thus, different persistency strategies can be applied for different consistency requirements to minimize system overhead and response delay. Game state storage also needs to be reliable and robust to any failure. If redundancy is applied for fault tolerance, then the replica consistency, responsiveness, and load balance issue also have to be studied [78].  
On the other hand, user content persistency in virtual worlds is still short of attention. With the growth of user content, however, this aspect is becoming increasingly important. Content persistency requires that a user's data and content can be permanently preserved if the user has not departed from the virtual world. Compared to state data, user content files normally have a larger size (e.g., multimedia files), but are less frequently updated. Thus, the main concern is distinctive [79], which includes storage efficiency (i.e., reliability to storage space), bandwidth cost, data access latency, and content integrity. Furthermore, if user content can be shared with other users, view consistency is needed, which requires that two users can see the same set of objects if both are interested in them.
## 6 Efficiency Performance
### Cost of Communication  
This subsection analyzes authentication schemes by comparing the communication cost of the schemes of [PERSON] et al. [25], [PERSON] et al. [26], [PERSON] et al. [28], [PERSON] et al. [29] and our work for vehicular networks. Generally, in a public channel environment for vehicular networks, the communication cost creates a message-tuple sent from a vehicle to others. Thereby, this paper supposes that the output of a hash function is \(160\) bits, the output of the timestamp is \(32\) bits, the output of the BPC point \(P=(P_{x},P_{y})\) is \((512+512)=1024\) bits, and the output of the ECC point is \((160+160)=320\) bits. The size of the message is excluded in this process. The comparison of cost of communication is tabulated in Table 6 and the analyzed schemes are compared in Figure 7.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Schemes** & **Signing Messages** & **Verifying Messages** \\ \hline [PERSON] et al. [25] & 27.21\% & 81.65\% \\ [PERSON] et al. [26] & 27.21\% & 77.81\% \\ [PERSON] et al. [28] & 68.21\% & 52.32\% \\ [PERSON] et al. [29] & 52.31\% & 64.23 \\ [PERSON] et al. [31] & 68.21\% & 52.32\% \\ \hline \hline \end{tabular}
\end{table}
Table 5: Cost of computation comparison.  
Figure 7: Cost of communication comparison.  
As tabulated in Table 6, the cost of communication of our work is 352 bits, which decreases by \(\frac{1376-352}{1376}\approx 74.42\%\), \(\frac{1376-352}{1376}\approx 74.42\%\), \(\frac{992-352}{992}\approx 64.52\%\), \(\frac{1024-352}{1024}\approx 65.63\%\), and \(\frac{992-352}{992}\approx 64.52\%\), respectively, against the schemes of [PERSON] et al. (2015); [PERSON] et al. (2016); [PERSON] et al. (2018); [PERSON] et al. (2019) and [PERSON] et al. (2011).
the whole area, the use of these models may not be easy because they require detailed information regarding hydrological, geotechnical, and geochemical parameters. Therefore, the geophysical method has been widely applied to estimate soil depth because it can quickly and cost-effectively provide various soil characteristics across an entire area. Electromagnetic waves have been used to measure electrical resistivity [12] and electrical conductivity [2], and the measured values can be converted into soil depths. Refs. [13; 14] used seismic survey to predict soil depth and however, the studies merely showed the distributions of results without methodological content for picking soil depth. In addition, the applied previous geophysical methods require special reference values to determine soil depth and additional invasive experiments to enhance the reliability of the estimated soil depth.  
This study proposes a graphical bilinear method to estimate soil depth based only on seismic survey. A seismic survey was performed, and the dynamic cone penetration test (DCPT) was also used to verify the soil depths deduced by the suggested technique. The measured information, including geological map, location, particle distribution, and distribution of seismic wave velocity were introduced first. Then the graphical bilinear method for determining soil depth, is demonstrated. The estimated soil depths using the suggested method are compared with values deduced by the dynamic cone penetration tests and their reliability is assessed.
# Survey of Smart Parking Systems
## 7 Discussion and Open Problems
### User Preferences  
The main gap identified in the extensive search is the poor identification of user preferences for establishing efficient routes to available parking slots or the choice of an optimal parking slot based on those preferences.  
In this context, papers were published that mentioned user preferences as part of the process of finding and selecting parking slots, but they did not detail how they were implemented [10; 13; 14; 300; 301]. Only in MADM (multiple attributes decision-making guidance algorithm) was the use, classification, and implementation of driver preferences described [274].  
Due to the low suitability of this feature, we believe that intelligent parking systems have even greater potential if they implement these preferences as the main parameters. This will allow the systems to adapt the searches based on these variables, being more precise in the visualization of the information as far as drivers are concerned.  
These pre-search accuracies, together with a suitable algorithm, can make establishing optimal parking slots for each driver possible, thus reducing competition for a common space. That is, there are users who may prefer to park near their workplace while others may prefer to park as quickly as possible. This feature can decongest the competition between drivers for free places, because, by indicating the optimal places according to preferences, the drivers will be guided to them.