esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results
present the vertical distribution of P and S velocity perturbations (%) as well as the V\({}_{\rm P}\)/V\({}_{\rm S}\) ratio values. From WNW to ESE, profiles 1 to 7 demonstrate the different faults we encounter, the relation between the surface expression of these tectonic elements, and the gradual deepening of some of these faults in the Athenian plain (profiles 5-7). Despite the relatively low ray coverage at the SE of the area, inside the Athenian plain, profiles 5, 6, and 7 reveal a clear south-dipping fault plane in the tomographic images of the absolute body-wave velocities (Figures 12 and 13). More specifically, between the 9 and 16 km depth range, we can observe some sharp contrasts of body-wave perturbations (-5-6%), V\({}_{\rm P}\)/V\({}_{\rm S}\), and absolute velocities in profiles 6 and 7 (Figures 9-13). As we move inside the basin, these observations appear differentiated from the ones of the west (TNF), interrupting the continuity of the Thiassion fault zone. This discontinuity cross-cuts the Athenian basin and can be associated with the activity observed since the 16 January 2015 ML = 3.2 earthquake. This zone emerged after geophysical investigations and minor faults in Central and Western Attica [43]. The velocity structure throughout the area at shallow depths (-5 km) is expressed by higher values of V\({}_{\rm P}\) anomalies (%) and high V\({}_{\rm P}\)/V\({}_{\rm S}\) ratio values (>1.85). This is mainly related to unconsolidated Plio-Pleistocene and Holocene formations [7; 46] (Figure S1), such as the ones on the southern shores of Attica. Profiles 1-8 show a negative P-wave anomaly (\(\sim\) -8%) between 0 and 15 km depth in the NE and SW edges. The velocity anomalies (15-25 km distance in the sections), combined with the high V\({}_{\rm S}\) anomalies, form an area of lower V\({}_{\rm P}\)/V\({}_{\rm S}\) ratio in this rectangular region (-1.70-1.74). On 19 July 2019, the Mw = 5.1 earthquake occurred in an area that is characterized by a low body-wave velocity perturbation of about -10%. This anomaly is seen in both P and S models at a depth of 10-14 km in profile 8. At shallower depths in the same area, positive anomalies are seen, which indicates higher absolute body-wave velocities. The main shock of that sequence was located at a depth of approximately 8 km and coincided with the boundary where high- and low-velocity anomalies meet. When these anomalies are transformed into absolute velocities, the highest V\({}_{\rm P}\) of 6.7 km/s is observed at a depth of nearly 20 km in the same area. On the other hand, the lower to minimum values of V\({}_{\rm P}\) (4.9-5.2 km/s) are observed in the shallower eastern half of the study area, where younger sediments are located, and at a depth of around 12 km, east of Thiassionde0 ones, where the plioseismal area was situated.
# WUE and CO2 Estimations by Eddy Covariance and Remote Sensing in Different Tropical Biomes
## 2 Materials and Methods
### Description of Study Area
#### 2.2.2. Caatinga Site  
Measurements were carried out on a site managed by the Chico Mendes Institute for Biodiversity Conservation (ICMBio), and the micrometeorological tower is part of the NOWCDCB (National Observatory of Water and Carbon Dynamics in the Caatinga Biome, Figure 1) monitoring network. The campaign comprised the period from 1 January 2014 to 31 July 2015. The tower is located in a preserved Caatinga segment (BR-CST) within the Pajeu river watershed (7\({}^{\circ}\)58\({}^{\prime}\)05.20\({}^{\circ}\)S, 38\({}^{\circ}\)23\({}^{\prime}\)02.62\({}^{\prime}\)W, 430 m in altitude) in Serra Talhada city, Pernambuco state, Northeast Brazil. According to [PERSON]'s classification, the climate is semiarid (BSwh), with summer rainfalls occurring between December and May (85% of total precipitation) as reported by [27]. Mean annual precipitation is approximately 640 mm, and average air temperatures range from 23.1 to 26.7 \({}^{\circ}\)C [27]. Native species at the site are _Mimosa hostilis, Mimosa verrucosa_ and _Croton sonderianus_, while _Anadenanthera macrocarpa, Sponias tuberosa_, _Casalpinia pyramididis_, and _Ziziphus jozeiro_ can also be found, with a mean height of 8.0 m [27]. Rainfall was provided by a \"Instituto Nacional de Meteorologia\" (INMET) station near of site.
## 2 Antenna Design Procedure
For example, bow-tie-160-50 refers to the bow tie with a flare angle of 160\({}^{\circ}\) and a flare radius of 50 mm. As expected, while maintaining a constant flare angle of 160\({}^{\circ}\), an increase in the flare radius reduces the resonant frequency, since the effective length of the antenna is increasing. With flare radii of 63 mm, 73 mm, and 83 mm, the resonance of the bow tie with a fixed flare angle shifts to 1.36 GHz, 1.18 GHz, and 1.04 GHz, respectively. In particular, it is noted that as the flare radius is increased, the slope of the \(R_{in}\) and \(X_{in}\) curves becomes steeper. For a wide bandwidth, a more gradual slope for the \(X_{in}\) curve is desired. Next, based on the multi-resonance principle, two variants of the triple bow-tie antenna, shown in Figure 5, are investigated. The triple bow tie in Figure 5 consists of three of the previously studied bow ties, bow-tie-80, bow-tie-120, and bow-tie-160, combined in an overlapped fashion and centralized at the feed. Ideally, the superposition of the \(S_{11}\) responses of each individual bow tie results in an enhanced \(-10\) dB bandwidth. Bow-tie-40 is not included in the overlapped bow tie, since the differences between bow-tie-40 and bow-tie-80 are negligible, in terms of \(R_{in}\), \(X_{in}\), and the frequency shift. Bow-tie-80 is preferred since the \(-10\) dB bandwidth is slightly larger than that for bow-tie-40. Bow-tie-80, therefore, is included to supplement the lowest band, bow-tie-120 covers the middle band, and bow-tie-160 provides coverage in the highest band. Bow-tie-160 is especially important for bandwidth enhancement since, as determined by the flare angle study, as the flare angle increases the resonant frequency shifts to the right faster, facilitating a wider bandwidth. The triple bow tie in Figure 5 fits within a sphere with a 50 mm radius and has an electrical size, \(kr\), of 1.3. The simulated \(S_{11}\) is shown in Figure 6, and depicts a \(-10\) dB bandwidth enhancement with a value of 57.9% (1.24-2.25 GHz). Next, the triple bow tie  
Figure 4: Simulated (**a**) \(R_{in}\) and (**b**) \(X_{in}\) for bow tie with flare angle of 160\({}^{\circ}\) and flare radius of 50 mm (bow-tie-160-50), 63 mm (bow-tie-160-63), 73 mm (bow-tie-160-73), and 83 mm (bow-tie-160-83). Figure 5: Dimensions and geometry of the triple bow ties of same radii and varying angles (**a**) without and (**b**) with a circular top. in Figure 5a is modified by the addition of a symmetrical circular top loading onto both ends of bow-tie-80, and is shown in Figure 5b. The effectiveness of circular top loadings on bow-tie antennas for bandwidth enhancement is demonstrated in [10]. The circular top loading provides an increased electrical length, allowing for the lowest frequency to be shifted even lower, generating a broader bandwidth as shown in Figure 6. The antenna now has a \(-10\) dB bandwidth of 65.4% (1.08-2.13 GHz) and a smaller electrical size (1.13), since it is calculated at the lowest frequency in the bandwidth of the antenna.
## 5 Results and Analysis
### Experimental Analysis Using Vibration-Damping Materials
Through analysis, it has been determined that the resonance frequency is proximate to the resonance, resulting in a significant amplitude response of the impact plate and a corresponding increase in charge voltage. Accordingly, the optimal approach to achieve effective vibration damping is to adjust the resonance frequency during sensor design. Upon experimentation with vibration-damping materials, such as rubber and sponge, it was discovered that inherent parameters, including the rigidity constant, k, had a primary impact on the vibration-damping effect. As k decreases, there is an increase in the resonance frequency that triggers a larger amplitude response of high-frequency vibration sources. The implementation of vibration-damping materials is thereby effective in reducing the resonance effect and achieving the optimal treatment of vibration damping. In the absence of vibration-damping materials and with the sensor rigidly connected to the test bench, K can be considered infinite. As a result, the vibration from the vibration source is entirely transmitted to the sensor, leading to voltage fluctuations within the range of 0-3 V. This situation results in the effective signal from the grain impacting the force plate being drowned out. When rubber is employed as the damping material, its stiffness constant, k, is approximately 30 kN/m, leading to high rigidity. Consequently, when the vibration source frequency is proximate to the sensor vibration frequency, a substantial amplitude response occurs, and the detected voltage value is around 2.6 V. This results in a direct submergence of a portion of the voltage signal produced by the grain hitting the stress plate. Upon implementing EVA foam as the damping material, the vibration-damping effect becomes more pronounced. The amplitude response of the interference source is effectively absorbed by the vibration-damping foam material. Additionally, the peak voltage output is regulated within 1.2 V, ensuring that the voltage signal generated by the grain impacting the stressed plate is not drowned out. This study analyzed and verified the two-degree-of-freedom vibration system using kinetic knowledge. Through multiple sets of comparative tests, it was demonstrated that vibration-damping materials had a positive effect on weakening the vibration interference of the sensor, thereby enhancing the detection accuracy of the sensor.
# Delineation of the Flooded Areas in Urban Environments Based on a Simplified Approach
## 1 Introduction
Recent studies have shown that adopting a more complex approach for case studies without sufficient observations for calibration is not contradictory, while the added value of a continuous approach is significant in the characterization of the design hydrograph attributes [25]. Alternatively, event-based approaches still represent a good solution for diminishing the uncertainties related to hydrologic modelling parametrizations [26]. Despite the long rainfall time series available at Tulcea meteorological station, there were no data concerning both (i) the generated street flow during torrential rains and (ii) the corresponding discharges at the outlets of the urban sewage system. The only available information (photographs of flooded urban areas) was for two rainfall events. Consequently, the data used for calibration and validation were the volume stored in the depression areas as unique values (not a time series of the volume storage). The flood volume is more relevant than the peak discharge for flood extent evaluation, as well as for approaching different drainage solutions, in an urban environment. Since a continuous simulation involves the risk of model overparameterization, an event-based approach was adopted. The main goal of our study was to obtain relatively reliable results using fast hydrological modelling coupled with a volume-based flood approach in order to reliably evaluate the flooded urban areas under extreme rainfall events. This approach is imposed by the limited input data compared to a distributed and coupled hydrological-hydraulic 2D model. Based on convenient simulation times, a large number of simulations could be undertaken, analysing a significant number of scenarios, mostly related to the functionality of the sewage system. For calibration and validation purposes, crowdsourced data (mainly photos) are used [27; 28; 29]. Crowdsourced data, even if not at the desired resolution or accuracy, may contain relevant information concerning urban areas with important landmarks. Based on this type of data, a water level can be conveniently estimated, and by using GIS tools coupled with an area DTM, the flood extent and the flood volume can be obtained. Various ways of reducing and controlling surface runoff were reviewed. Upon their calibration, new scenarios for future urban developments or climate change conditionscan be considered. It is considered that this approach can be easily implemented for urban conditions of other towns, where the sewerage outlets discharges are not registered. This paper is organized as follows: Section 2 introduces the Materials and Methods used in this study; Section 3 provides a Case study and the description of the Mathematical model; Section 4 contains the Results of the mathematical modelling; Section 5 is devoted to Discussion; and Section 6 presents Conclusions.
# Approaches and Challenges in Internet of Robotic Things
## 2 IoRT: An Overview
### Definitions and Concept of IoRT
#### 2.1.1 How Does Communication Take Place in IoRT?  
In H2M interactions, humans provide input to IoT devices in the form of speech, text, and images, among other things. The IoT device, including sensors and actuators, then interprets the input, analyzes it, and reacts to the user via text or a visual display, such as facial recognition or speech recognition. By automating programs, machines may communicate with one another. M2M communication needs machine-level instructions. Communication can happen without human assistance. A point-to-point connection between two network devices is known as an M2M connection, e.g., alerts from a smart washing machine and smart meters. M2H communication is the most prevalent sort of communication utilized when robots assist humans in their regular activities. It is a type of interaction in which humans collaborate with smart systems and other machines to complete a task by using tools or gadgets, e.g., fire alarms and traffic lights [8; 17; 18]. The IoRT platform maintains the robotic thing's functionalities and technologies. The platform's major capabilities enable robotic things to achieve their main goals, such as communication among robotic things, data flow, IoRT device organization for accessing and maintaining devices, and IoRT device cooperation inside and between the platforms. This is all done to form IoRT applications via the IoRT platform infrastructure. IoRT platform technologies enable elasticity, usability, and productivity [4; 9; 19; 20]. Sharing of data between robots is the responsibility of IoRT platforms to connect data (in the cloud and at control centers) to robotic objects, devices, and people (IoRT environment) [21; 22].
## 7 Design Applications
### Design Rules Implementation  
To investigate the feasibility of innovative design (and design rules) for new road/rail structures, a series of comprehensive simulation scenarios were carried out to establish the dynamic and fatigue design rules. Hence, the environmental wind gust and buffeting effects of HSV were considered for the design of large portal gantries. Initially, the results of a comprehensive field-study [39] were used to verify the outcomes of the new simulation system for the large portal gantries. Full-scale field study data were collected using a full set of measuring devices (pressure and height sensors, ultrasonic anemometer, and video cameras) to record the physical quantities during the passages of HSVs under a large portal gantry. Figure 10 shows the real-world gantry structure, where the pressure waves were measured at different heights above the HSV in the slow lane as well as the virtual CAD model (vehicle, gantry zones).  
For the zonal-CFD technique, the geometry of the HSV was simplified and the gantry legs were neglected owing to minimal effects on the buffeting results. The far-filed gantry boom over the opposite traffic lanes was also modeled because of its negligible pressure  
Figure 10: (**a**) Typical passage of an HSV under portal gantry for field study [39] and (**b**) CAD model of HSV and partial gantry boom.  
effects (for CFD simulation, not for vibration simulation). The surface geometry of the simulated HSV developed in earlier stages was imprinted in the moving vehicle zone and the height of the vehicle was adjusted to 4.4 m. The partial 3D geometry model of the gantry boom includes the traffic signals and a large traffic sign, which were modelled to resemble the field study conditions. Both HSV and gantry zones are imported into main fluid domain (air at 25 \({}^{\circ}\)C) using appropriate coordinate system. The discretization of the main domain as well as moving/stationary zones were carried out using advanced mesh control routines to create finer mesh zones for the areas of interest in the domain (top of the HSV and area around the gantry boom).  
The numerical simulations of HSV passage under the virtual portal gantry model are shown in Figure 11a at different time steps. The variations of peak calculated pressure against the height above the centerline of the HSV and its smoothed design graph are also shown in Figure 11b.  
Figure 11: (**a**) Snapshots of HSV passage under gantry boom, (**b**) calculated time-history pressure results, and (**c**) calculated peak pressure and its smoothed design curve.
## 2 Methodology
### Verification of the Vulnerability Assessment Performance  
The correlation of the vulnerability indexes based on actual pollution occurrences was used for the validation of the accuracy of groundwater vulnerability maps [12; 43]. The Pearson and Spearman correlation coefficients between the vulnerability indexes and nitrate concentration were adopted to verify the assessment results.  
The Spearman correlation coefficient is defined as the Pearson correlation coefficient between ranked variables. The vulnerability index \(V_{i}\) and nitrate concentration \(C_{n}\) of the samples are converted into ranks and calculated for the correlation coefficient.  
As mentioned above, the Pearson and Spearman correlation coefficients can be used to verify the static vulnerability assessment performance. However, it is necessary to evaluate the vulnerability results from a time perspective. To achieve this goal, the method reported in the work of [PERSON] et al. [44] was modified. From a temporal perspective, the difference between the groundwater vulnerability level and the level of nitrate concentration changes is a good validation criterion. The vulnerability indexes and nitrate concentration changes are strictly divided into the same number of categories and the difference in the levels is then calculated by computing the absolute difference between the two maps.  
The two nitrate datasets obtained in the study area (separated by almost 20 years) provide an opportunity to measure the effects of the vulnerability assessment using nitrate concentration changes. Two maps of nitrate concentration in shallow groundwater of the study area can be attained by spatial interpolation and the variations can be calculated by subtraction of the two maps. The magnitude of the changes can be compared with the vulnerability indexes and the consistency of the two graphs is a good measurement criterion. Since there is no obvious trend, the ordinary kriging (OK) was used instead of the universal kriging (UK) to obtain the spatial nitrate concentration map. The spatial interpolation of the nitrate concentration includes the following steps: (1) the nitrate concentration was logarithmically transformed, as shown in Equation (6); (2) kriging interpolation was performed; and (3) the interpolation result was converted to the original form.  
The data-driven weighting method proposed in this paper is based on the Monte Carlo algorithm or genetic algorithm. This method considers both single factors and the relationship between factors. It overcomes the subjectivity of weight determination. It is theoretically applicable to a variety of hydrogeological environments. It is a generalized weight determination method.
# An Experimental Study on Repairing of Reinforced Concrete Beams Having Damaged Longitudinal Bars
## 3 Results and Discussion
### Load-Displacement Curves
#### 3.2.3 Rigidity of the Beams  
The rigidity of the beam is an important characteristic that defines the behavior of the beam under loading. The rigidity of each beam was calculated as its rigidity at a deflection of 5 mm, which is the displacement of the undamaged beam at a service load (calculated as the span/480 in the ACI 440.2R [40]). A comparison of the rigidity of each beam to the reference beams is shown in Table 7. It can be seen that the damaged beam (RefB-D) lost more than 91% of the rigidity of the undamaged beam (RefB). Among all the repaired specimens, only RB1-SNSM-S and RB7-EBR-S specimens, which were repaired with steel bar, reached the rigidity value of the undamaged reference beam (RefB). The greatest increase in the rigidity was observed in the RB7-EBR-S specimen with 46%.  
The beams repaired with the SNSM (RB1-SNSM-S) and EBR (RB7-EBR-S) methods by using steel rebars enhanced the beam rigidity by 7% and 46% of the undamaged reference beam rigidity, respectively, and increased the beam rigidity by 1100% and 1533% of the damaged beam rigidity, respectively. The other repaired beams had generally lower rigidity. The beams repaired with GFRP rebars has less rigidity than the beams repaired with steel rebars. When the rigidity value of the beam repaired with the SNSM (RB2-SNSM-G) method by using GFRP rebar is compared with the values of the NSM (RB3-NSM-G) method, it can be seen that the NSM method provided more rigidity than the SNSM method. All repaired beams had significantly more rigidity than the damaged reference beam (RefB-D), with an increase in rigidity between 289% and 1533%.
# AHC: Advanced Network-Hiding Access Control Framework
## 2 Related Work
### SPA Enhancement  
In terms of enhancing SPA, current research mainly focuses on improving the SPA authentication mechanism. Ref. [27] proposes a lightweight Port Knocking scheme to resist TCP replay attacks and port scanning. Ref. [28] proposed an OpenSPA scheme that supports custom access policies. Ref. [29] proposes a new single-packet authentication method HSPA. It can transparently authenticate remote clients and addresses two main issues in its design: resource shortage attacks and a lack of correlation between the authentication and establishment processes. The studies [30] use the time synchronization HTOP mechanism to improve single-packet authorization authentication technology to enhance the security of the SDP architecture. The first communication packet between the SDP client and the SDP gateway under the SDP architecture is the SPA authentication packet. However, to resist DDoS attacks, the study [31] proposed that symmetric cryptography should be used to build a lightweight single-packet authorization mechanism instead of using public keys. This is a cryptosystem, so the security of distribution and storage of SPA keys is crucial. [PERSON]. [32] proposed a \"Honeykeys\" deception mechanism to reduce the risk of key leakage caused by centralized storage of SPA keys but did not consider the security of SPA key distribution. [PERSON]. [33] used the HKDF scheme based on the key derivation function and HMAC to achieve symmetric key distribution. [PERSON]. [34] implements key agreements among multiple participants based on secure multi-party computation.  
Through the comprehensive analysis of relevant domestic literature mentioned above, it can be found that the current zero-trust security protection mainly relies on single-mode Single Packet Authorization (SPA) technology, which mainly provides hiding protection and demonstration for the services of the device itself. However, the application scenarios of SPA technology are mainly limited to data centers, and its extensibility is relatively insufficient, making it difficult to meet the increasingly complex and changing network security needs. Therefore, in the process of promoting the development of zero-trust security protection technology, it is necessary to further explore and research more flexible and scalable solutions to cope with the constantly changing network security challenges.