esa-sceva/satcom-chunk-collection huggingface dataset:
# Assimilation of Earth Observation Data Over Cropland and Grassland Sites into a Simple GPP Model
## 2 Data
### Eddy Covariance Flux Tower GPP  
Eddy covariance (EC) is an established technique to quantify turbulent exchanges of CO\({}_{2}\) between the surface and the atmosphere (for a descrption see [PERSON] et al. (2018); [PERSON] et al. (2018)). European flux data have been collected from the European Flux Database Cluster (EFDC, a repository of flux observations for various European projects), and the FLUXNET2015 database (a coordinated effort to harmonize flux observations for as many sites as possible globally ([PERSON] et al., 2018)). For the purposes of this study, only flux measurements over cropland and grassland were acquired for a total of 58 sites.  
Among the different GPP products available in the two datasets we selected half-hourly GPP estimated from net ecosystem exchange (NEE) measurements quality-checked, filtered for low friction velocity conditions, gap-filled and partitioned as consolidated in the FLUXNET methodology ([PERSON] et al., 2018). Specifically, we used the GPP product computed using an annual friction velocity threshold to filter NEE, NEE gap-filling based on Marginal Distribution Sampling ([PERSON] et al., 2018), and finally estimates GPP using night-time flux partitioning ([PERSON] et al., 2018). Daily GPP values were computed by aggregating half-hourly GPP estimates, and eventually aggregated to 8-day mean daily value for the validation against modelled GPP. Surface homogeneity of all EC sites was visually inspected using Google Earth to eliminate sites with obvious heterogeneity of land cover within the MODIS pixel (e.g., ([PERSON] et al., 2018; [PERSON] et al., 2018)). As a result, only the EC site FR-Avi (Avignon, France) was excluded for further analysis. The location of the retained sites and period covered by flux measurements is shown in Figure 1 (30 cropland sites and 27 grassland sites).
## 6 Experimental Results and Analysis  
The metrics considered in the study were packet delivery ratio (PDR), received signal strength indicator (RSSI), signal to noise ratio (SNR) and time on air (ToA), which are the parameters chosen to assess the performance of the LoRa communication uplink and downlink in the different environments of the Chirinche Bajo community. The experiments were conducted during weather variations with sun and rain from 5-23 June 2022.  
The LoRa gateway was placed in a fixed position during all measurements, while the end nodes were placed in different locations as illustrated in Figure 10. The evaluation was segmented into three groups: the first expedition was in the morning hours, the LoRa network was configured with SF at seven, a cloudy day with showers and a breeze was present; the average temperature was 16 \({}^{\circ}\)C, the relative humidity was in the range of 74-86% and the average UV radiation was in two indexes.  
In the second evaluation, the SF was parameterized at nine and the weather was partially cloudy. At the end of the evaluation (POS G and H), the sun was present, the wind blew with medium intensity; the average temperature was 12 \({}^{\circ}\)C, the relative humidity was in a range of 74-89% and the average ultraviolet radiation was in one index. Finally, on the third excursion, it was a sunny day with high-intensity winds,  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Metrics** & **Units** & **Meaning** \\ \hline PDR & \% & Package Delivery Ratio \\ \hline RSSI & dbm & Received Signal Strength Indicators \\ \hline SNR & db & The signal-to-noise ratio \\ \hline ToA & ms & Time on Air \\ \hline \hline \end{tabular}
\end{table}
Table 4: Summary of evaluated metrics.  
Figure 10: End nodes in test positions.  
was 19 \({}^{\circ}\)C, the relative humidity was in a range of 53-68% and the average ultraviolet radiation was in four indices. This evaluation was carried out from 16h00.
# Application of Molecularly Imprinted Polymers in the Analysis of Waters and Wastewaters
## 5 Application of MIPs for the Detection of Different Classes of Contaminants
### Heavy Metals
#### 5.1.6 Manganese  
Manganese has found many applications in ferrous metallurgy, electrochemical and chemical processes, as well as in many foods and pharmaceutical industries. Despite being essential for some vital human process, its maximum allowed level in water should not exceed 0.1 mg L\({}^{-1}\), as its accumulation has a negative impact on the nervous system [43].  
A multiwalled carbon nanotube ion-imprinted polymer (MWCNT-IIP) was developed for manganese ions detection and extraction. The ion imprinted layer was synthesized on the surface of vinyl functionalized MWCNTs via free radical polymerizing using methacrylic acid as a functional monomer. A modified platinum electrode was then designed through immobilization of the above-mentioned polymer in nafion. Under the optimized conditions, Mn(II) ions could be sensed with a linear range from 1 to 5 ppm with an LOD of 0.0138 mM using differential pulse voltammetry [57].
## 5 Discussion
### Possible Mitigation for Current Systems  
In this subsection, we explore measures that can enhance the resilience of WLANs against APT attacks. As previously discussed, vulnerabilities in authentication mechanisms can be exploited, enabling attackers to transition from online to offline attack vectors. Offline attacks utilize high-performance computing to accelerate malicious activities. One essential precautionary step involves thwarting the conversion of online attacks into offline ones. This can be achieved by deploying authentication protocols specifically designed to withstand such attacks, but care must be taken to prevent downgrade attacks. However, this approach poses compatibility challenges, as certain devices may not support enhanced protocols, leaving them susceptible to these attacks. This is particularly evident in smaller devices like IoT devices.  
As a result, an alternative approach emerges: segregating networks according to their distinct security requirements. This strategy involves partitioning various network components into separate entities, each tailored to handle specific types of data and devices. For instance, one could establish a dedicated network exclusively for IoT devices, keeping them isolated from networks hosting computing devices or storing sensitive data. By implementing this segregation, the vulnerability to cyber attacks is significantly diminished. This separation can be achieved through different means, ranging from comprehensive hardware segregation to the implementation of sophisticated network management techniques. Full hardware segregation entails physically isolating different network segments, ensuring that each operates independently without any direct connections. Alternatively, network administrators can leverage solutions such as IP subnetting or Virtual LANs (VLANs) to create logical partitions within a shared physical infrastructure.  
An important consideration is to avoid using routers provided by Internet service providers, as these devices often include additional features that grant the ISP greater access to the local network. It is crucial to carefully select access points, opting for devices with no documented firmware vulnerabilities. Choosing open-source firmware options such as DD-WRT [93] and OpenWRT [94] can offer a viable alternative, but it is essential to ensure proper implementation to avoid misconfigurations, particularly for less experienced users.  
Furthermore, deploying robust firewall configurations can effectively prevent unauthorized access. Firewalls can be specifically configured to restrict the flow of WLAN information through the gateway to the ISP, enhancing network security. Additionally, leveraging tunneling protocols can minimize the amount of information exposed to potential attacks on the gateway, reducing the attack surface and mitigating the risk of man-in-the-middle attacks. These measures collectively contribute to bolstering network security and safeguarding sensitive data from potential threats.
###### Abstract  
This paper presents a Dual-sideband Optical Carrier Suppression (DSB-OCS) technique which is used to generate an optical millimeter-wave (mm-wave) signal in radio over fiber (RoF) systems. The proposed system employs a Dual-Electrode Mach-Zehnder Modulator (DE-MZM) and a carrier of 40 GHz mm-wave for data transmission through the RoF systems. Characteristics determining the performance of the system, among which are the modulation index, phase imbalance and dispersion parameters, are included. The performance evaluations of the system show that the mm-wave signal output power follows MZM's transfer function when the modulation index is raised. Moreover, the generated optical mm-wave signal power is affected by phase imbalance and optical splitting ratio. It is observed that the optical fiber dispersion influences the DSB-OCS system by decreasing the amplitude of the mm-wave and the signal-to-noise ratio (SNR).  
mm-wave; RoF; dual sideband optical carrier suppression; optical modulation index; optical fiber dispersion; phase imbalance +
_Photonics_
## 2 Materials and Methods
### Mobility Indicator Design
#### 2.2.5 Path Availability  
Path availability is a portion of the path availability time between two nodes \(x\) and \(y\):  
\[PA(x,y)=\left\{\begin{array}{ll}\frac{\sum_{t=start(x,y)}^{T}A(x,y,t)}{T- start(x,y)}&T-start(x,y)>0\\ 0&otherwise\end{array}\right. \tag{12}\]  
where \(A(x,y,t)\) is a random variable, such that if the path from node \(x\) to node \(y\) is available at time \(t\), its value is \(1\); otherwise, its value is \(0\). \(start(x,y)\) is the start time of communication service between nodes \(x\) and \(y\).  
Average path availability is the average value across pairs of nodes that meet specific conditions.  
\[PA=\frac{\sum_{x=1}^{N}\sum_{y=x+1}^{N}PA(x,y)}{P} \tag{13}\]  
In which \(P\) is the number of node pairs \((x,y)\) that satisfy \(T-start(x,y)>0\).
# Optimized Sensors Network and Dynamical Maps for Monitoring Traffic Noise in a Large Urban Zone
## 3 Dynamap Approach
### The Dynamap Network for Z9: Implementation, Location, and Operation
#### 3.3.2 The Sensor Locations in Z9  
As mentioned in Section 3.1, we have at our disposal 24 sensor stations which need to be distributed within Z9 in an optimized fashion. The natural choice is to get an equal number of sensors per group that is \(N_{g}=4\), and somehow well separated from each other. To this end, we have first plotted all road groups, \(g_{i}\) (shown separately in Figure 5), together in Figure 6, so that one can get a full picture on the spatial distribution of equivalent levels, \(L^{(1\mathrm{h})}_{\mathrm{eq}}(t_{\mathrm{ref}},s)\), in the pilot zone Z9 [86; 87; 88; 89; 90]. The selection of sensor locations is shown in Figure 6 by the full black triangles, and the corresponding addresses are reported in Table 2, while the yellow circles correspond to the sites where additional measurements have been performed for validation purposes (see Section 4.1).  
\begin{table}
\begin{tabular}{c l l l l} \hline \hline
**Code (g\({}_{i}\))** & **Address** & **Code (g\({}_{i}\))** & **Address** \\ \hline
135 (1) & Via Lambruschini & 121 (4) & Via [PERSON] \\
137 (1) & Via Maestri del Lavoro & 127 (4) & Via Quadrio \\
139 (1) & Via Bruni & 129 (4) & Via Crespi \\
144 (1) & Via D’Integnano & 138 (4) & Via Novaro \\ \hline
108 (2) & Via [PERSON] & 106 (5) & [PERSON] \\
124 (2) & Via Grivola & 123 (5) & Via Galvani \\
125 (2) & Via Abba & 136 (5) & Via Comasina \\
145 (2) & [PERSON] & 151 (5) & Via Veglia \\ \hline
115 (3) & Via Fara & 109 (6) & Via Stelvio \\
116 (3) & Via Moncalieri & 114 (6) & Via [PERSON] \\
120 (3) & Via Baldinucci & 117 (6) & Via Fermi \\
133 (3) & Via Maffucci & 140 (6) & Via Jenner \\ \hline \hline \end{tabular}
\end{table}
Table 2: Location of the 24 Dynamap noise monitoring stations (cf. Figure 6). For each sensor, the code number, group index \(g_{i}\) (within parenthesis), and name of the street are reported [91].
# Self-Organizing Control of Mega Constellations for Continuous Earth Observation
## 1 Introduction
The above control methods cannot be applied to mega constellation scenarios. For the requirement of continuous Earth observation of mega constellations, this paper analyzes the relationship between orbital planes, coplanar adjacent satellites, and coverage performance and proposes a continuous novel coverage constraint that relates to intersatellite motion only. The new constraint can be applied to the self-organizing control of mega constellations. The APF method is adopted to solve the self-organizing control problem in this work. Considering the large range of relative motion between constellation satellites, the scale-independent relative orbital elements (SIROEs) are proposed as the APF control variables. SIROEs have been proposed in our preliminary work [23; 24], which have clear geometric interpretations, concise expressions, and high precision for relative motion with near-circular reference orbit and arbitrary intersatellite separation, which are particularly suitable for mega constellation satellites. The stability of the proposed self-organizing control is proven based on the Gaussian equations and [PERSON]'s theory. An ideal APF control variable of the controlled satellite should have the same time derivative as the target satellite states under a two-body Keplerian motion circumstance. Finally, the GW-2 constellation is simulated to verify the proposed self-organizing control method. The results indicate its goodness of control effect and ground-coverage performance. The continuous coverage constraint is analyzed in Section 2.1. The configuration requirements of mega constellations are given here. The artificial potential functions for a single satellite and the self-organizing control rules for coplanar satellites are studied in Section 2.2. The detailed stability proofs of the proposed artificial potential functions are given in Section 2.3. The performance of self-organizing control for continuous coverage is evaluated based on a GW-2 constellation in Section 3. Conclusions are provided in Section 4.
# Fault Diagnosis of Wind Turbine Planetary Gear Based on a Digital Twin
## 4 Case Study  
### Experimental Process  
This paper uses a Spectra Quest custom-manufactured wind turbine drive system fault diagnosis test stand as an example. It consists of a motor, spur gear, planetary gear, magnetic powder brake, console (PC), sensor, and acquisition device (STM32 development board). The parameters of the strain gauge sensor are shown in Table 1. In this paper, a wind turbine's planetary gear fault diagnosis system based on a digital twin is tested by the planetary gear's normal and broken tooth fault states. The normal and faulty gears used for replacement are the planetary gear of the planetary reduction box, as shown in Figure 11, and the parameters of each gear option are shown in Table 2. For more relevant work of the real wind turbine speed, according to the characteristics of the wind turbine, the spindle speed was low, the motor speed was set to 750 r/min, the frequency was set to 12.5 Hz, the impeller in the spindle speed was just about 18 r/min, the torque was set to 33 N\(\cdot\)m, and the sampling frequency for the experiment was 500 Hz. Using Ansys simulation software, through the transient simulation analysis (sun wheel speed 87 RPM, planet carrier torque 33 N\(\cdot\)m), as shown in Figure 12, it can be observed that the strain gauge sensors pasted outside the planetary gear ring gear, meshing gear, and tooth root area can be measured with the maximum strain signal. Hence, the planetary gear sensor layout's wind machine is shown in Figure 13.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Type** & **Grid Size (mm)** & **Base Size (mm)** & **Resistance Value (\(\Omega\))** \\ \hline
350-3 AA & 3.0 \(\times\) 3.1 & 7.3 \(\times\) 4.1 & 350 \(\pm\) 0.1 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Strain gauge sensor parameters.  
\begin{table}
\begin{tabular}{l l} \hline \hline
**Items** & **Gear** \\ \hline Number of teeth & 36 \\ Module (mm) & 1 \\ Pressure Angle & 20 \\ Crest height (mm) & 1 \\ Top clearance (mm) & 0.25 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Gear main parameters and geometric dimensions.  
Figure 11: Experiment with planetary gears in different states.  
Figure 12: Equivalent stress nephogram.  
First, the strain gauge sensor is connected to the STM32 development board. The other end of the development board is connected to the signal amplifier to amplify and filter the received signals. The other end of the bridge is connected to a PC to realize the real-time acquisition of various data of the wind turbine's planetary gear. The visualization of the collected data is completed by an ECharts chart, and the collected data are stored in the MySQL database. Then, the classification diagnosis of real-time data and the continuous updating optimization of the fault diagnosis model are realized by a machine learning algorithm supported by MATLAB software. Finally, the User Interface (UI) interface is established in the Unity3D platform, and the diagnostic results and data are displayed visually in the interface.
# Energy Efficient Data Transmission for Sensors with Wireless Charging
###### Abstract  
This paper studies the problem of maximizing the energy utilization for data transmission in sensors with periodical wireless charging process while taking into account the thermal effect. Two classes of problems are analyzed: one is the case that wireless charging can process for only a limited period of time, and the other is the case that wireless charging can process for a long enough time. Algorithms are proposed to solve the problems and analysis of these algorithms are also provided. For the first problem, three subproblems are studied, and, for the general problem, we give an algorithm that can derive a performance bound of \((1-\frac{1}{2m})(OPT-E)\) compared to an optimal solution. In addition, for the second problem, we provide an algorithm with \(\frac{2m}{2m-1}OPT+1\) performance bound for the general problem. Simulations confirm the analysis of the algorithms.  
wireless charging; thermal effect; data transmission 18 2018 18 511 10.3390/s18020511 10.  
* To the best of our knowledge, this is the first work to study data transmission in sensors taking into account the thermal effects in wireless charging and uses a periodical charging period to eliminate the thermal effect.
* This paper considers the problem where the wireless charging continues for a limited period of time. Algorithms are provided and the performance bounds of the algorithms are also analyzed.
* This paper also considers the problem where the wireless charging continues for a long enough time. Algorithms are provided and the performance bounds of the algorithms are also analyzed.
* The simulations are conducted to evaluate and confirm the performance of the provided algorithms.  
The rest of this paper will first introduce the motivation and the problem formulation, and then study the problem with different conditions. After that, the simulation results are presented, then the related work follows, and finally it concludes this paper.
## Abstract  
Cryopreservation has been shown to be a reliable method for preserving coral biodiversity in the face of present environmental threats. To be successful in cryopreservation, the effect of cryopreservation on molecular parameters is an important factor that needs to be taken into consideration. The goal of this research was to see how cryopreservation affected protein expression in _Seriatopora calientrum_ larvae. Larvae were subjected to vitrification (2 M ethylene glycol + 1 M propylene glycol, 40% \(w/v\) Ficoll and 1.2 \(\times\) 10\({}^{18}\) /m\({}^{3}\) gold nano particles) and laser warming (300 V, 10 ms pulse width, 2 mm laser beam diameter). Successfully vitrified and warmed larvae were maintained for 8 and 24 hours, respectively, before protein extraction. The proteins with various molecular masses were separated using one-dimensional gel electrophoresis, and target proteins were identified using liquid chromatography-tandem mass spectrometry. After vitrification and nano-laser warming, keratin-associated protein 9-2 was found to be reduced, although mitogen-activated protein kinase 13 exhibited the reverse tendency. The reduction in keratin-associated protein 9-2 in coral larvae following vitrification and nano-laser warming is thought to have had a severe impact on the skeletons of the coral larvae, resulting in a poor survival rate. Mitogen-activated protein kinase (MAPK) is a key regulator of cells. Consequently, it is probable that freezing insults for larval development activated MAPK. The existing understanding of the influence of cryopreservation on protein expression was improved by this work.  
cryopreservation; coral; vitrification; laser warming; conservation
# Windowed Hamming Distance-Based Intrusion Detection for the CAN Bus
## 2 Related Work
Correspondingly, the window-based method is more robust. [PERSON], [PERSON] et al. [13] propose the framework for assembling CAN frames into windows and computing their corresponding histograms. It is fed into a multi-class IDS classifier to identify classes of traffic windows. Window-based detection approaches are more robust than packet-based approaches. They capture more robust features and relationships between packets within a window. This paper uses a window-based detection method combined with the Hamming distance method. Compared with the method that only applies the Hamming distance [12], we use the characteristics of time series to make the model more robust. According to the results of the experiment, the detection effect of our method is also more excellent.