esa-sceva/satcom-chunk-collection huggingface dataset:
# Adaptive Suppression Method of LiDAR Background Noise Based on Threshold Detection
###### Abstract
Most research focuses on the method of changing the operating voltage of APD, which is equivalent to adjusting the APD multiplier, for background radiation noise suppression, but these methods have a low response speed of adjustment due to the bandwidth limitation of the high voltage source of APD so that they cannot be quickly adjusted according to the background radiation changes in the instantaneous field of view when the laser radar is scanning the large field of view. In this paper, the influence of background radiation noise of LiDAR on the detection performance is analyzed, the principle of CFAR and the implementation method of threshold control are studied, and then an adaptive suppression method of background radiation noise of LiDAR through threshold adjustment is proposed. Based on the traditional adjustment mode, the signal identification threshold is automatically adjusted by the cascade current steering architecture with a back-end digital-to-analog converter (DAC) correction to achieve CFAR control of LiDAR. In order to solve the problem of quantization deviation of a short time in noise detection, a dynamic comparator is used to replace the traditional continuous comparator, and the comparator implementation structure and threshold selection requirements are studied. Finally, comparative experiments are carried out by using this method on LiDAR, and the experimental results are analyzed.
# Water Supply Systems for Settlements with Arsenic-Contaminated Groundwater--Making the Right Choice
## 3 Results and Discussion
### Central Supply Approach
#### 3.4.1 Central Supply Approach for Kanijza
The settlements included are: Kanjiza (K0), Velebit (K1), Zimonjic (K3), Martonos (K6), and Horgos (K10) in Kanjiza municipality and Novi Knezevac (NK) in the neighbouring municipality. The configuration of the proposed water supply system with all of the basic infrastructure facilities is shown in Figure 11.  
According to the proposed solution for a central water supply, water is abstracted and treated onsite in the village of Velebit, and then, via the main pumping station, it is directed to the settlements in the system. The water treatment plant has a capacity of 100 L/s and applies a simple treatment scheme consisting of aeration/degasification, retention, sand filtration, and disinfection. Clean water flows into the pumping pool. Velebit settlement is supplied by a booster pump unit, which draws water directly from the system pumping pool. The main pumping unit of the system displaces water to all settlements in the system. Zimonjic is directly connected to the main pipeline. In Kanjiza, two pipeline branches are directed towards Martonos and Horgos (one branch) and the other branch to Novi Knezevac. The settlements Kanjiza, Martonos, Horgos, and Novi Knezevac have their own water towers (VT in Figure 11). To increase the pressure and connect to the water towers in these settlements, at node 3, the construction of a pumping station with two blocks is planned: one block to Martonos and the other to Horgos. Before entering Novi Knezevac, another pumping station is planned, connected to the water tower in Novi Knezevac. The transmission network configuration includes water pipelines ranging from DN400 down to DN140 and includes 32.6 km of pipeline among settlements in total. The estimated value of the central supply for the MS Kanjiza system is shown in Table 6 below. The total cost of the central supply system is almost EUR 8.8 million, with annual operational costs of EUR 0.6 million/year. The pipelines represent approximately 54% of the investment costs and 36% of the operating costs.
## 3 Results
### Evaluation of the Elastocaloric Properties
One possible solution to reduce the heat exchange time and increase the cooling power could be to work in forced convection, using a fan. Future works are in progress to explore this possibility. Finally, it can be interesting to make a comparison between the elastocaloric performance of shape memory alloys reported in the literature [9] and NR_1.5S, the most promising NR formulation among the ones tested. Three parameters are considered for the comparison reported in Table 8: the deformation imposed during the elastocaloric tests (\(\Delta\varepsilon\)), \(\Delta\Gamma_{\text{cool}}/\Delta\sigma\) where \(\Delta\sigma\) the maximum stress needed to deform the material, and \(\Delta\Gamma/\Delta\varepsilon\) \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Physical Parameter** & **Sample** & \multicolumn{3}{c}{**Maximum Deformation**} \\ \hline  & & **300\%** & **400\%** & **500\%** \\ \hline  & NR\_1.5S & 18.3 & 20.4 & 17.2 \\ \(\tau_{\text{c}}\) stretching phase (s) & NR\_2.5S & 21.1 & 21.1 & 17.1 \\  & NR\_3.5S & 22.3 & 20.7 & 23.9 \\ \hline  & NR\_1.5S & 51.8 & 57.8 & 57.1 \\ \(\tau_{\text{c}}\) stretching phase (s) & NR\_2.5S & 39.8 & 56.6 & 62.3 \\  & NR\_3.5S & 58.6 & 53.6 & 62.1 \\ \hline  & NR\_1.5S & 12.6 & 11.3 & 13.4 \\ h stretching phase (W/(m\({}^{2}\)K)) & NR\_2.5S & 21.1 & 21.1 & 17.1 \\  & NR\_3.5S & 22.3 & 20.7 & 23.9 \\ \hline  & NR\_1.5S & 17.8 & 15.9 & 16.1 \\ h retraction phase (W/(m\({}^{2}\)K)) & NR\_2.5S & 24.9 & 17.5 & 15.9 \\  & NR\_3.5S & 17.0 & 18.6 & 16.1 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Characteristic time of temperature dampening (\(\tau_{\text{c}}\)) and heat transfer coefficient (h) calculated in the stretching and retraction phases of the samples. NR exhibits a strain two orders of magnitude higher than that of shape memory alloys. NR needs to be stretched several times its original length to demonstrate noteworthy elastocaloric performance, presenting a drawback in the context of designing compact air conditioners. Consequently, the elastocaloric strength \(\Delta\)T/\(\Delta\varepsilon\) in natural rubber is two orders of magnitude lower. In the literature, a suggested approach to address this challenge is to work with pre-strained natural rubber [9]. On the other hand, the parameter \(\Delta\)T\({}_{\text{cool}}\)/\(\Delta\sigma\) is two orders of magnitude higher compared to shape memory alloys, which is an important advantage as the stress required to deform natural rubber is well below that required for metal alloys and quite close to the stresses involved in current air conditioners.
# Using Satellite-Derived Vegetation Products to Evaluate LDAS-Monde over the Euro-Mediterranean Area
## 2 Material and Methods
### LDAS-Monde  
Within the SURFX Land Data Assimilation System (LDAS, [9; 12; 14; 38; 39]), recently extended at the global scale (LDAS-Monde, [15]), satellite-based products of soil wetness and of vegetation can be jointly assimilated using a simplified extended Kalman filter. This method uses finite differences to compute the flow dependency between the observations and the analyzed variables. Equations of the analysis update equations can be found in [14]. In the three-layer soil hydrology version of ISBA, the analyzed variables are the root-zone soil moisture and LAI, each containing 12 values corresponding to the possible 12 plant functional types of the considered pixel (no vegetation, rock bare soils, snow and ice, deciduous forests, coniferous forests, evergreen forests, summer crops, winter crops, irrigated crops, grasslands, tropical grasslands or wetlands, from ECOCLIMAP, which is the vegetation map used in SURFX, [40]). These two variables are the main interest in the photosynthesis process since the root-zone soil moisture and LAI are the main drivers of the evapotranspiration process. Once a day, the model is stopped, and the analyzed variables are adjusted according to the observations and their relative errors compared to the ones assigned to the open-loop simulations (when the model runs without any assimilation).
# Innovations in Sustainable Agriculture: Case Study of Lis Valley Irrigation District, Portugal
## 4 Results and Discussion
### Case Study: The OG for Water Management Improvement in the Lis Valley Irrigation District, Portugal  
Portuguese agriculture is strongly influenced by its Mediterranean climate, implying that drainage and irrigation are techniques of utmost significance for soil conservation and land productivity. The high rainfall temporal variability, associated with frequent droughts, makes rainfed crop production very poor. In addition, crops with higher market prices, like fruit and vegetables, require irrigation to grow during summer's dry season. For this reason, nowadays, most economically feasible crops are irrigated. Also, considering the positive impacts of irrigation to mitigate the effects of expected climate changes that are expected to increase rainfall vagaries, the length of drought periods, and water scarcity, the Portuguese PDR gives a higher priority to the improvement of irrigation systems, with the development and rehabilitation of irrigation infrastructures to reduce water losses, improve management, and foster agricultural competitiveness. The LVID is located in the Portuguese Center region, is 2000 ha, and is a public irrigation district with hydraulic infrastructures dating back from 1957. It is managed by the Water Users' Association (WUA). The main crops are forage corn, forage grass, horticultural, orchards and rice. Water is supplied by an open-channel conveyance network from weirs installed along the Lis river and tributaries, and by pumping from drainage ditches [38]. The OG (OGLIS) aims to improve water management in the Lis Valley Irrigation District (LVID). The partners are two research teams from the Polytechnic Institute of Coimbra, as well as from the University of Coimbra, the Lis Valley Water Users Association, the Regional Board of the Center Region of the Ministry of Agriculture, three farmers' companies, and a group linked with the AKIS systems. The objectives of OGLIS are to enhance competitiveness and environmental quality through monitoring and experimental actions [39]. These objectives are to be achieved through an innovation approach based on the improvement of management processes, following up several advances of knowledge and practices quantified by several indicators related with water-pumping energy efficiency, off- and on-farm irrigation and drainage, water quality, operational water demand and distribution plans, and their economic assessment. The experimental procedure focuses on the soil and water management system in individual farmer fields, creating a dynamic knowledge extension with LVID farmers.
## 2 Materials  
### Remote Sensing Data  
The base data used in this experiment were two GF-2 images, denoted as image A and image B. Image A was imaged on 19 February 2021, with a fused resolution of 1 m, a longitude of 111.8\({}^{\circ}\) E and a latitude of 34.7\({}^{\circ}\) N at the center point, and the number of rows and columns being 27,403 \(\times\) 28,616. Due to the limitation of computer performance, it is not possible to process the whole image, so a part of the area was selected as the data set. To verify the universality of the pseudo-TCT, the selected area required rich types of ground objects, including mountains, lakes, fields, bare soil, rural areas, cities, etc., and a rich variety of building and road styles. The location of each region is shown in Figure 1, which are region 1 (suburban), region 2 (rural with lake), region 3 (mountain) and region 4 (suburban) with the size of 3001 \(\times\) 3001; region 5 (urban) was the size of 3000 \(\times\) 3000; mountain 1 (mountain) was the size of 2147 \(\times\) 2534; and mountain 2 (mountain) was the size of 2629 \(\times\) 1370.  
Image B was from the Gaofen image dataset (GID) [38], a land cover classification datasets produced by Wuhan University, and the images in the GID have been specially processed without latitude and longitude information. It was a GF-2 image, with a resolution of roughly 3-4 m and a dimension of 6800 \(\times\) 7200 pixels, as shown in the following Figure 2. GID has no resolution information, which was the resolution we infer from the size of the ground objects.  
Figure 1: Selected remote sensing data. (**a**) whole GF-2 image; (**b**) region 1, corresponding to B in (**a**); (**c**) region 2, corresponding to C in (**a**); (**d**) region 3, corresponding to D in (**a**); (**e**) region 4, corresponding to E in (**a**); (**f**) region 5, corresponding to F in (**a**); (**g**) mountain 1, corresponding to G in (**a**); (**h**) mountain 2, corresponding to H in (**a**).  
Figure 2: A remote sensing image from GID. (**a**) original image; (**b**) land cover label; (**c**) built-up label.
## 4 Results
### Test Results Versus Map Results
These results agree with the dynamic solicitations of the cycles since RDEs 5 and 6 were generated to be less aggressive than RDEs 1 to 4. In the case of NO\({}_{\rm X}\) errors, a clear tendency was not found. In any case, errors were kept below 5% in all cases. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**CO\({}_{2}\) [kg]**} & \multicolumn{3}{c}{**NO\({}_{\rm X}\) [g]**} \\ \cline{2-7}  & **Test** & **Map** & \(\varepsilon_{\text{co2}}\) & **Test** & **Map** & \(\varepsilon_{\text{NOx}}\) \\ \hline RDE 1 & 11.56 & 11.38 & 1.61\% & 28.89 & 29.32 & \(-1.50\%\) \\ RDE 2 & 11.36 & 11.21 & 1.34\% & 31.16 & 30.04 & 3.62\% \\ RDE 3 & 11.68 & 11.82 & \(-1.19\%\) & 32.08 & 33.28 & \(-3.74\%\) \\ RDE 4 & 12.21 & 12.38 & \(-1.34\%\) & 31.55 & 31.96 & \(-1.31\%\) \\ RDE 5 & 10.66 & 10.57 & 0.77\% & 27.85 & 28.87 & \(-3.65\%\) \\ RDE 6 & 9.68 & 9.61 & 0.79\% & 18.38 & 17.57 & 4.39\% \\ \hline \hline \end{tabular}
\end{table} 
Table 7: CO\({}_{2}\) and NO\({}_{\rm X}\) pollutants from RDE cycles versus map emissions. Figure 14: NO\({}_{\rm X}\) emissions comparison between RDE 1 and engine map i urban (**a**,**d**,**g**), rural (**b**,**e**,**h**), and motorway (**c**,**f**,**i**) driving phases. As previously commented, during the tests, it was not possible to measure the PM along the entire driving cycle. However, three different periods of 500 s corresponding to three zones (urban, rural, and motorway) in RDE 1 have been considered. Figure 15 shows RDE PM mass emissions compared to those obtained from the steady-state map. Figure 15 emissions show a great correlation between emissions measured and emissions from the steady-state map. Table 8 shows the accumulated values of each one of these three phases and the total values represent their summation. Looking at PM mass errors, the higher discrepancies appear during the urban and motorway periods, which are characterized by more dynamic conditions due to steeper  
Figure 15: RDE 1 periods PM urban (**a**), rural (**b**) and motorway (**c**) mass emissions [g/s] test versus engine map. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**PM Mass [g]**} \\ \cline{2-4}  & **Test** & **Map** & \(\epsilon_{\text{PM}}\) \\ \hline Urban period & 0.285 & 0.276 & 3.4\% \\ Rural period & 0.383 & 0.385 & \(-0.5\%\) \\ Motorway period & 0.672 & 0.643 & 4.4\% \\ TOTAL & 1.340 & 1.303 & 2.8\% \\ \hline \hline \end{tabular}
\end{table} 
Table 8: PM mass emissions from RDE 1 versus map emissions. accelerations. In any case, the interpolation can also be a very helpful tool to estimate the PM in an RDE cycle since the obtained errors are relatively low considering the complexity of this species.
###### Abstract  
The 5 th Generation Mobile Communication (5G) plays a significant role in the Fourth Industrial Revolution (4 IR), facilitating significant improvements and innovations in various fields. The 3 rd Generation Partnership Project (3 GPP) is currently standardizing the Authentication and Key Management for Application (AKMA) system for the 5G convergence applications (5G CAPPs). The Transport Layer Security (TLS) is recommended as the application-specific \(\text{U}^{\ast}\) protocol between User Equipment (UE) and Application Function (AF) to securely transmit the AKMA identifiers of UE as well as guarantee traffic protection. Among TLS protocols, session resumption in TLS 1.2 and the Pre-Shared Key (PSK) modes of TLS 1.3 are particularly desirable for \(\text{U}^{\ast}\). Unfortunately, the integration of PSK options of TLS 1.3, namely PSK-only, PSK-(EC)DHE, and 0-RTT (0 Round-Trip Time) modes, with AKMA has not yet been thoroughly investigated; hence, security, performance, compatibility, and effectiveness remain uncertain. In response, this paper explores the integration of the TLS 1.3 PSK options with AKMA and investigates the said metrics by conducting formal security verification and emulating exemplary applications. According to the formal verification and experimental results, the PSK-(EC)DH mode shows a security strength trade-off with efficiency. On the one hand, the 0-RTT mode demonstrates better efficiency but exhibits drawbacks on forward secrecy and replay attacks. The result suggests that 0-RTT mode has to be approved to ensure seamless integration of the TLS 1.3 PSK option with AKMA. In addition, adjustment on the AKMA architecture is also imperative to enhance security level.  
3 GPP AKMA; 5G/6G security; 5G CAPP; TLS 1.3; ProVerif; formal security verification
## 4 System Implementation and Experimental Results
### Motion Sensors
Before the motion capturing session, the Shimmer3 units were calibrated using the Shimmer 9 DOF Calibration Application, that is also derived by the same company. This application implements an automated process that calculates the calibration parameters for Shimmer's integrated accelerometers, gyroscopes and magnetometers sensors. These calibration parameters are finally stored in the unit memory, so as the sensor measurements can be automatically corrected before they are sent to the paired device (e.g., a computer that functions as base station). In the sequel, the collected sensors measurements, for both type of sensors, are processed and filtered as described in the previous Section. Then, the DoFs rotations \(\theta_{i}\), for the upper limb model, are extracted by Equation (12) for the shoulder, Equations (13) and (14) for the elbow and Equations (15) and (16) for the wrist joint, respectively. In the following Subsections, the 3D reconstructed upper limb joints trajectories are presented in common rehabilitation exercises, as the elbow's flexion-extension, the shoulder's abduction-adduction and the wrist's flexion-extension exercise. In the processing stage, the sensor's sampling period is selected as \(T=20\) msec, while the values of the model lengths are defined as \(l_{c}=0.2322\) m, \(l_{ua}=0.3348\) m, \(l_{fa}=0.2628\) m and \(l_{h}=0.1944\) m, which were estimated for the subject's height of \(H=1.80\) m. Furthermore, the first two experimental cases do not account for any wrist rotation, since there was not any sensor node attached over the subject's hand. Hence, the corresponding DoFs angles are assumed as \(\theta_{6}=\theta_{7}=0^{\circ}\).
# Analysis of the Scalability of UWB Indoor Localization Solutions for High User Densities
## 4 Localization Schemes and MAC Considerations
### Two-Way Ranging  
As the name suggests, a two-way ranging technique requires bidirectional communication between the tag and each of the involved anchors. Two of the most common TWR schemes, called single sided TWR and symmetrical double sided TWR (SDS-TWR), are shown in Figure 2. Generally, the tag initiates the communication sending the first message at time T\({}_{0}\). The anchor, after a certain period (T\({}_{\text{reply}}\)), replies with a message containing the packet timestamps T\({}_{1}\) and T\({}_{2}\), which are the reception moments of the first packet and the reply to the tag, respectively. Moreover, these timestamps are unknown to the mobile node. At this point the tag can compute the ToF, which is in turn used to estimate the distance between the tag and the anchor (assuming that the propagation speed is known). A more accurate range estimation is possible if the number of exchanged packets is doubled, e.g., as it happens in SDS-TWR.  
The exchanged messages, two or four depending on the TWR algorithm, are used to determine the distances between the anchors and the tag, which, based on the performed distance measurements, will compute its position using one of the previously mentioned localization estimation techniques. This approach also has several advantages and disadvantages.
###### Abstract  
Deformation predictions in high Concrete Face Rockfill Dams tend to underestimate observed settlements due to scale effect and breakage phenomena that cannot be adequately captured by laboratory tests. This paper presents a Visco-Elasto-Perfectly Plastic (VEPP) model for predicting deformations in high Concrete Face Rockfill Dams (CFRDs) that addresses these challenges incorporating explicitly key rockfill parameters like grain size and post-compaction porosity, which influence both the non-linear elastic and plastic behaviors of rockfill. The VEPP model enables deformation prediction while using standard laboratory test results. The model's effectiveness was demonstrated through its application to the 233 m high Shuibuya Dam, the tallest CFRD in the world. The VEPP model predictions closely align with observed deformations throughout the dam's construction, impoundment, and early operational stages. By using physically meaningful parameters, the model reduces the uncertainty associated with the empirical assessment of model parameters using back-analysis from similar projects. While the VEPP model offers improved predictive accuracy, particularly during early design phases, further advancements could be achieved by refining the creep formulation and accounting for grain size evolution during construction. This approach has the potential to optimize the design and construction of future high CFRD.  
rockfill; deformation; plasticity; dam; CFRD; numerical model +
Footnote †: journal: applied sciences