esa-sceva/satcom-chunk-collection huggingface dataset:
# Simple HPLC-PDA Analysis to Determine Illegal Synthetic Dyes in Herbal Medicines
## 3 Results and Discussion  
### Optimization of Extraction  
Extraction was needed before the detection stage to remove all impurities that may interrupt the results. The most common extraction methods were liquid-liquid extraction, solid-phase extraction, membrane filtration, and cloud point extraction [24]. The extraction procedures significantly influenced the recovery of most dyes, and the selection of suitable extraction methods depended on the target samples [25]. For a rapid and straightforward HPLC-PDA analysis to determine ten synthetic dyes in herbal medicines, this study referred to the Chinese government's HPLC-UV methods [15] to distinguish synthetic colorants in herbal medicines. The HPLC-UV analysis uses 70% ETOH as an extraction solvent. This study investigated the recoveries of ten synthetic dyes in herbal medicines among several candidate solvents to search for an optimal extract solvent. As shown in Figure 1, the recoveries of several synthetic dyes were far below the acceptance criteria when 70% ETOH or 70% MeOH was used for the extraction solutions. The solvent combination consisted of 50 mM ammonium in 70% MeOH and 100 mM HCl in 70% MeOH, resulting in higher recoveries than 70% ETOH. Among candidate solvents, however, 100 mM ammonium acetate in 70% MeOH was considered an optimal solvent to extract the synthetic dyes from herbal medicines (Figure 1). When the selected extraction solvent was applied for three herbal medicines, most of the analytes indicated satisfactory recoveries greater than 80% (Figure 2). When considering these results, ten synthetic dye adulterants in herbal medicines can be successfully released through double extraction using 100 mM ammonium acetate in 70% MeOH without an additive purification process. [PERSON] et al. [6] demonstrated that 50% MeOH as an extraction solvent in developing the LC-MS/MS method can determine synthetic dyes in herbal medicines, and the recoveries obtained from the test method were in the range between 83.4-92.7%. [PERSON] [26] argued that the mixed solution comprising MeOH and 100 mM ammonium acetate can result in an excellent extraction of synthetic colors in foods.  
Figure 1: Recoveries of ten synthetic colorants obtained from extraction using various solvents from Hawthorn fruit spiked with the color mixture solution.  
Figure 2: Mean recoveries of each synthetic dye obtained from each herbal medicine spiked in low, medium, or high concentrations of the mixed ten standard solutions using the proposed HPLC-PDA analysis.
# Deformation and Stress Analysis of Pile-Supported Immersed Tunnels under Seismic Loads
## 2 Methodology
### Numerical Model
#### 2.2.2 Material Properties  
Parameters \(M\), \(e_{0}\), \(e_{1}\), \(\lambda\), \(K\)r, and \(v\) are common to the Cam-Clay model (MCC) for marine soil. In the MCC model, the slope of the critical line (CSL) in the \(p\)-\(q\) coordinate system is \(M=6\sin\!\varphi/(3-\sin\!\varphi)\); the slope of the normal consolidation line (NCL) in the \(e\)-\(l\)\(n\)\(p\) coordinate system is \(\lambda=\)\(\mathrm{Cc}\)/2.3 and the slope of the swelling line in the \(e\)-\(l\)\(n\)\(p\) coordinate system \(K\)r = (0.2-0.5) \(\lambda\); and the relationship between the soil void ratio and the consolidation ratio (\(OCR\)) at a given location is \(e_{1}=e_{0}+\lambda lnp_{0}+K\)\(rln(OCR)\)[40].  
Figure 4: Schematic of the numerical model. 1—Level surface; 2—Angle of incidence; 3—Seismic waves in X, Y, Z directions; 4—Incident wave.  
During consolidation, the void ratio of the seabed decreases as pore water is drained, leading to subsidence of the seabed and the marine structures above it. The hydrostatic pressure of the seabed foundation will change significantly under large deformations. Accordingly, in finite element calculations, the Darcy permeability coefficient \(k\) in the soil is related to the change in the void ratio \(e\) during soil deformation. In the calculation, the permeability of the seabed soil is \(k_{\rm i}=C_{\rm f}\,e^{3}/(1+e)\), where \(C_{\rm f}=k_{0}(1+e_{0})/e_{0}{}^{3}\) is the empirical coefficient [41], and \(e_{0}\) and \(k_{0}\) are the initial void ratio and permeability, respectively.  
SCP produces hardening behavior under the action of seismic waves, and the DP hardening model is coupled with a porous elastic material (_Proelastic_) to form a sand pile drainage channel used to reduce the exceeded porous water pressure in the subsea foundations. The immersed tunnel, gravel cushion, and backfill are practically designed with impermeable and rigid materials. Therefore, they are modeled with linear elastic (_elastic_) materials with the parameters given in Table 2.
# A Hierarchical Fusion SAR Image Change-Detection Method Based on HF-CRF Model
## 3 Experiment and Analysis  
### Datasets  
In this study, we utilized eight publicly available SAR image sets to generate mean difference maps and log-ratio difference maps. To construct the training set, we employed data enhancement techniques. The effectiveness of our algorithm was then evaluated using four SAR datasets, with the composition of the training set being readjusted for each validation process. All datasets consist of two temporal phase maps and the corresponding GTs. The first dataset is a remotely sensed image of the Berne area with a pixel resolution of \(301\times 301\), as shown in Figure 10; the second dataset is a remotely sensed image of the Ottawa area with a pixel resolution of \(290\times 310\), as shown in Figure 11; the third dataset is a remote sensing image of the Mexico region with a pixel resolution of \(256\times 256\), as shown in Figure 12; the fourth dataset is a remote sensing image of the San Francisco region with a pixel resolution of \(512\times 512\), as shown in Figure 13.
# Worldwide Coverage Mobile Systems for
## 4 Ku-Band Antennas Design Techniques  
Currently, there is a growing demand for antenna systems aimed at satellite communications, either GEO or LEO constellations, with low weight and small size factor to be used in mobile communications with global coverage and wide bandwidth. In this kind of applications, where those features are a strong requirement, planar antenna systems could be a good option to fit those specifications.  
This section introduces the main design techniques used to construct antennas operating in the Ku-band. Usually, to achieve the required specifications, i.e., radiation pattern gain, directivity, aperture, etc., the antennas are combined to set-up arrays. First, we briefly introduce some state-of-the-art examples and, afterwards, the next sections introduce the types of antennas that are most commonly used in satellite communications, with special focus on the Ku-band transmission/reception.  
Figure 1: Phase array antenna.
## 7 Conclusions  
This study presents real-time path planning based on JPS in a structured urban environment at 30 kph. At beginning, a vector GIS map is built, which contains a GPS position, a direction and lane information. Next, a global path is planned according to the GIS map database for a driverless car. Then, the JPS algorithm is adopted for driverless cars and for local path planning. Finally, 125 simulation experiment results show that the JPS algorithm is an efficient method for real-time local path planning, and it can find the optimal path rapidly in the structured urban environment.  
This paper was supported by the National Natural Science Foundation of China (Grant No. 61403426, 61403427), State Key Laboratory of Mechanical Transmissions of Chongqing University  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Algorithm** & **Scene1** & **Scene2** & **Scene3** & **Scene4** & **Scene5** & **Average** \\ \hline A* & 0.5226 & 0.4689 & 0.4241 & 0.4327 & 0.6288 & 0.8257 \\ JPS & 0.02113 & 0.01792 & 0.02003 & 0.0179 & 0.0259 & 0.02058 \\ PRM & 8.2568 & 6.2625 & 6.7503 & 7.0778 & 6.9995 & 7.0694 \\ VFH & 1.3215 & 1.0611 & 1.2958 & 1.0376 & 1.1192 & 1.1670 \\ RRT & 0.0900 & 0.1085 & 0.0703 & 0.0777 & 0.0834 & 0.0860 \\ \hline \hline \end{tabular}
\end{table}
Table 2: The time complexity evaluation comparison (secs) of different algorithms.  
Figure 16: Four algorithms simulation experiment results.  
(SKLMT-KFKT-201602), State Key Laboratory of Robotics and System (HIT) (SKLRS-2017-KF-13). Meanwhile, we thank Ref. [19]'s authors, Figures 9 and 10 are based on that paper.  
[PERSON] and [PERSON] conceived and designed the experiments; [PERSON] and [PERSON] performed the experiments; [PERSON] and [PERSON] analyzed the data; [PERSON] wrote the paper.  
**Conflicts of Interest:** The authors declare no conflict of interest.
## 3 Results and Discussion
### Results of HHO-RF Model  
To obtain the best combination of \(m_{\text{try}}\) and \(n_{\text{tree}}\), 8 HHO-RF models with the maximum number of iterations of 500 and variable numbers of Harris hawks ranging from 20 to 250 were developed. The fitness curve of these HHO-RF models checked by \(RMSE\) can be found in Figure 7. As shown in Figure 7, there is no significant change after 350 iterations. But the escaping energy of the rabbit has a relationship with the maximum number of iterations in the HHO algorithm according to Equation (3). The change of the maximum number of iterations may affect the optimization performance of the HHO algorithm. Hence, 500 and 150 were chosen as the best parameter combination of HHO-RF modeling in view of the excellent prediction performance.  
As shown in Figure 8, the established HHO-RF model can predict and evaluate the \(PPV\) with \(R^{2}\) of 0.94, \(MAE\) of 0.17 and \(RMSE\) of 0.23 for training datasets and \(R^{2}\) of 0.94, \(MAE\) of 0.29 and \(RMSE\) of 0.34 for testing datasets. After comparing the prediction performance obtained by the RF model and HHO-RF model, the comparison results show that the HHO-RF model can be used to predict the PPV with a higher level of prediction accuracy.  
Figure 8: PPV prediction by HHO-RF model: **(a)** training datasets; **(b)** testing datasets.  
Figure 7: The fitness curve of the HHO-RF model with various numbers of Harris hawks and 500 iterations.
## 2 Materials and Methods
### Determination of Individual Polyphenols by High-Performance Liquid Chromatography (HPLC)  
Alongside spectrophotometric analysis of total polyphenols, HPLC analysis was performed to evaluate individual ones. For this purpose, the HPLC system 1260 Infinity II (Agilent Technology, Santa Clara, CA, USA) was utilized. The system is composed of a quaternary pump, a vial sampler, and a diode array detector (DAD) and equipped with a Poroshell 120 EC C-18 column (4.6 \(\times\) 100 mm, 2.7 \(\upmu\)m). Initially, extracts were filtered over PTFE filters (0.20 \(\upmu\)m pores) and then injected into the system at a volume of 10 \(\upmu\)L, and the flow rate was adjusted to 1.0 mL/min. The DAD was used for monitoring UV-Vis spectra in the wavelength range from 190 to 600 nm. Two mobile phases were used, orthophosphoric acid (0.1% water solution) as mobile phase A and methanol (100%) as mobile phase B. The gradient used for separation was arranged under the following conditions: 0 min 5% B, 3 min 30% B, 15 min 35% B, 22 min 37% B, 30 min 41% B, 32 min 45% B, 40 min 49% B, 45 min 80% B, 48 min 80% B, 50 min 5% B, and 53 min 5% B. Identification of polyphenols was conducted by comparing the extract and standards through retention times and UV-Vis spectra. Anthocyanins were detected at 520 nm, phenolic acids at 320 nm, and quercetin-3-rutinoside at 360 nm. A calibration curve for cyanidin-3-galactosidase was generated in the range from 1 to 500 mg/L (r\({}^{2}\) = 0.9998; LOD = 0.0006 mg/L; LOQ = 0.0019 mg/L), for cyanidin-3-arabinoside from 1 to 150 mg/L (r\({}^{2}\) = 0.9996; LOD = 0.29 mg/L; LOQ = 0.89 mg/L), for neochlorogenic acid from 5 to 150 mg/L (r\({}^{2}\) = 0.9992; LOD = 0.71 mg/L; LOQ = 2.15 mg/L), for chlorogenic acid from 5 to 500 mg/L (r\({}^{2}\) = 0.9997; LOD = 0.0002 mg/L; LOQ = 0.0006 mg/L), and for quercetin-3-rutinoside from 5 to 150 mg/L (r\({}^{2}\) = 0.998; LOD = 0.18 mg/L; LOQ = 0.55 mg/L). For each extract, two injections were conducted, and the results are presented as mg of polyphenol per kg of hydrogel beads (mg/kg).
## 4 Discussion
### Altitude Reporting  
In both manned and unmanned aviation, the flight altitude is determined by measuring the air pressure, but with different reference levels. In manned aviation, the air pressure at mean sea level (MSL) is generally chosen as the reference level and corrected by a certain amount for local deviations from the standard atmosphere (Air pressure = 1013.25 hPa, temperature at sea level = 15 \({}^{\circ}\)C, temperature gradient = \(-\)0.65 K per 100 m altitude). This is known as QNH altimeter pressure setting. Above a so-called transition altitude, the altimeter is set to the standard air pressure of 1013.25 hPa (known as standard QNH pressure setting). All ADS-B capable Mode A/C/S transponders are fixed to the standard air pressure for better comparability, regardless of the actual air pressure. For small UAS, on the other hand, the present air pressure at the launch site (AGL) is taken as the reference level, so that a flight altitude of 0 m is displayed on the ground. There are also differences in the preferred unit for altitude reporting. While commercially available UAS (such as DJI's systems in this case) use the metric system (altitude in meters), in manned aviation altitude is usually measured in feet. This inevitably creates potential source of error in mixed operations.  
It can be concluded that for multimodal communication it is essential to have a common data source for the reporting of altitude information. Preference should be given to the measurements of certified (and thus more reliable) sensors, i.e., the barometer of the transponder, as its altitude information can also be received by participants outside the UTM network. However, it must be noted that altitude information via Modes S is only transmitted with a resolution of 25 ft.
This study proposes a trust enhanced on-demand routing (TER) scheme, which takes inherent advantages of the TW algorithm for efficient trust assessment and an ad hoc on-demand distance vector (AODV). The proposed TER scheme uses the three-valued subjective logic (3 VSL) and Bayesian network theory. 3 VSL, which is a kind of advanced probabilistic logic, gives an accurate trust assessment result in the final computed opinion [11; 12]. This feature urges us to use 3 VSL in the proposed scheme because it defines trust as a threefold event by considering positive, negative, and neutral events. The neutral state expresses the posterior uncertainty which exists in trust generated by vehicles during an interaction. Prior uncertainty remains the same in most of the probabilistic trust models. Furthermore, the TW algorithm represents the vehicular network topology in the form of a matrix using 3 VSL operations. The performance is analyzed to validate the accuracy of the proposed TER in terms of throughput, packet loss, and end-to-end (E2E) delay. Additionally, the execution time of the TW algorithm is analyzed by comparing it with another route search algorithm called  
Figure 2: A possible scenario in future vehicular Internet of Things. Assess-Trust (AT) [13]. The execution times of the TW and AT schemes are evaluated by using two real-world on-line datasets i.e., Advogato and Pretty Good Privacy (PGP).
## 7 Experimental Research
### Energy Losses Due to Phase and Timing Synchronization  
Additional energy losses occur during packet transmission due to inaccuracies in phase and timing synchronization. Figure 11 (red line) shows the experimental BER for the bit rate \(R=1.42/T\). The same figure shows the results of calculating the BER using simulation (Section 5). As we can see, the difference between simulation and experiment at \(BER=10^{-4}\) is about 1 dB.  
These additional energy losses are explained by the fact that the experimental SDR setup used a standard phase-locked frequency control system and a timing synchronization system designed to process classical BPSK signals with a rectangular amplitude pulse of  
Figure 10: Signal sequence at the output of the transmitter (**a**) and spectral characteristics (**b**).  
duration \(T\). The resulting additional energy losses of 1 dB can be reduced to 0.1-0.2 dB by using improved phase and clock synchronization systems working with FTN signals, which can provide less phase and timing errors.
## 5 Implementation  
### Development Environment  
Our proposed method's development environments are summarized in two tables, one for the manufacturer and the blockchain network, and another for the IoT gateway and IoT device, as shown in Tables 2 and 3. Both manufacturer and blockchain network reside in Ubuntu Linux 16.04 LTS under the VMWare virtual environment. The virtual environment was installed on a Windows 10 host machine with Intel Core i5-7200U @2.50 GHz CPU and 4 GB memory. For the manufacturer, we used Express.js to generate a REST API. It provides GET requests for IoT gateways. Web3.js was used to facilitate communication between the manufacturer and the blockchain network. Additionally, we used Node.js as a programming language. Our blockchain network was based on Ganache. Ganache is a rapid Ethereum and Corda distributed application development [27]. Solidity and Node.js were used as programming languages to write a smart contract.  
Table 3 describes the development tools and technologies for implementing the IoT gateway and the IoT device. Raspbian Buster was installed on the Raspberry Pi 3 Model B with 1 GB memory for both the gateway and the IoT device. The gateway used SQLite3 as a database management system to store device information and firmware updates' metadata from smart contracts. Express.js was used to generate REST API requests (POST and GET requests) and Web3.js to enable communication between the IoT gateway and the blockchain network. Additionally, Node.js was used as a programming language for both the gateway and the IoT device. Nevertheless, the IoT device had C as an additional programming language for IoTity's code. Besides, IoTivity Lite 2.0.5 was installed to make this device an IoTity server. Additionally, the IoT device was connected to the Dallas temperature sensor.
# Satellite Measured Ionospheric Magnetic Field Variations over Natural Hazards Sites
## 5 Results
### Earthquakes
#### 5.2.1 Earthquake M6.5 Severo-Kurilsk, Russia  
The so-called Pacific Ring of Fire, with its subduction zones, is a hotspot of volcanic and earthquake activity. Here we focus on the M6.5 earthquake near Severo-Kurilsk, Kuril Islands, Russia, where the data enables common CSES and _Swarm_ investigations, see Figure 3. This provides a testbed at the Kuril-Kamchatka trench to compare high magnitude events at different times and hypocenters. CSES FGM1 shows an increase in fluctuations for all three components, i.e., the variations are higher after the earthquake occurrence. _Swarm_ B had only one post-crossing. _Swarm_ A VFM shows higher variations than _Swarm_ C VFM, the three components have varying maxima in different frequency bands (wavelike transition between frequencies and scales).  
\begin{table}
\begin{tabular}{l l l l l l l}
**No.** & **USGS ID** & **Event** & **Date** & **Mag** & **Depth** & **Satellite and Instrument** \\ \hline
1 & us1000 hacw & Severo-Kurilsk, RUS & 2018-10-10 & M6.5 & 20 km & CSES FGM1, _Swarm_ VFMs \\
2 & us1000 ge27 & Rio Caribe, VEN & 2018-08-21 & M7.3 & 146.8 km & CSES HPM (FGM1 and CDSM) \\
3 & us1000 gci & Ndoi Island, FJI & 2018-08-19 & M8.2 & 600 km & CSES HPM (FGM1 and CDSM) \\
4 & ci38457511 & Ridgecrest, USA & 2019-07-06 & M7.1 & 8 km & CSES HPM (FGM1 and CDSM) \\ \end{tabular}
\end{table}
Table 2: Investigated earthquakes with space based magnetic field measurements by LEO satellites.  
Figure 3: _Cont_.
## 1 Introduction
analyzed the properties of air dielectric strength under transmission lines during forest fires. The study examined the frequency of short-circuits between phases and short-circuits to the ground below transmission lines caused by forest fires. Since 2010, a total of 128 short-circuit incidents have been recorded, including 37 short-circuits between phases (28.9%). It was determined that the reduction in the dielectric strength of air below transmission lines occurs mainly in the flame area, and the flame height does not reach the region between phases [9]. [PERSON] measured the dielectric strengths of liquid nitrogen, GN\({}_{2}\), and CGN\({}_{2}\), and described the differences in dielectric strengths according to the electrode shape. In addition, gas temperature, vapor, and mist density influenced dielectric strength [10]. \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Variable** & **2005** & **2006** & **2007** & **2008** & **2009** & **2010** \\ \hline Number of forest fires & 516 & 405 & 418 & 389 & 570 & 282 \\ \hline Number of transmission line & 6 & 6 & 5 & 2 & 4 & 4 \\ breakdowns by forest fires & 2011 & 2012 & 2013 & 2014 &
\begin{tabular}{c} Average \\ (2005–2014) \\ \end{tabular} \\ \hline Number of forest fires & 277 & 197 & 296 & 492 & 384.2 \\ \hline Number of transmission line & 5 & - & - & - & 3.2 \\ breakdowns by forest fires & & & & & \\ \hline \end{tabular}
\end{table} 
Table 1: Number of forest fires and the number of transmission line breakdowns by forest fires. [PERSON] discovered that in flames without smoke, dielectric strength gradually decreased as the flame height increased. This was a result of the increase in relative air density when the flame was farther from the electrode [11]. [PERSON] examined the dielectric properties of air when a flame was between the cylinder-shaped rods and plane electrodes. There was a reduction of up to 32.1% in the flashover voltage when a flame was present compared to when it was absent. Furthermore, the corona wind extinguished the flame as the gap length and horizontal distance increased [12]. [PERSON] proposed guidelines for firefighting activities for fires occurring below transmission lines. Firefighting activities are proscribed when the flame approaches transmission lines. They are permitted when there is a distance of 3 m or more between the bottom of the transmission line and the top of the flame (only for transmission lines of 400 kV or less). In addition, it is recommended to cut off the power source when a flame is detected at the bottom of a transmission line [13]. Therefore, there is a need to study the possibility of physical damage due to the dielectric breakdown voltage of the air and flames when fires occur on the ground below DC transmission lines. This study was conducted according to the procedure in Figure 1. First, we measured the fire properties of each material using a cone calorimeter. Second, we analyzed the breakdown of insulation that occurred when a material was burned using the dielectric strength test. Finally, we confirmed the correlation between the two experimental results through correlation analysis.