esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 Airborne Instruments and Interface with the ATR-42
### CAROLS Radiometer
#### 2.1.1.1 General System Design  
CAROLS is a total power radiometer and has a simple structure and high theoretical sensitivity. The receiver was developed as a copy of the EMIRADII radiometer [9, 10], in collaboration between the TUD (Technical University of Denmark) and the LATMOS laboratory (Laboratoire Atmospheres, Milieux, Observations Spatiales). It is a fully polarimetric correlation radiometer using direct sampling [9, 10]. The antenna system comprises two large, identical Potter horns and two waveguide orthomode transducers (OMT). These provide dual-incidence measurements, useful for the estimation of soil moisture or ocean salinity from brightness temperatures.  
The CAROLS system periodically performs two-point calibrations, to calibrate the receiver gain and noise temperature by means of noise injection. In such a calibration system, the receiver looks at known sources and makes use of their associated outputs to infer the relationship between the output value provided by the A/D converter and the antenna temperature. A matched load is coupled with a noise source, which can be switched on and off, in order to measure two different brightness temperatures. Laboratory calibration of the instrument consists in determining a set of parameters relating the power received from the noise source to its physical temperature.  
All of the analog components are placed inside a double insulated and thermally regulated box and their physical temperatures are recorded in real time by means of temperature sensors. The accuracy of the receiver is highly dependent on the stability of the noise source and other components used in the noise injection circuitry.
# Anomaly Monitoring of Process Based on Recurrent Timeliness Rules (AMP-RTR)
## 4 Experimental Results
### Conduct Simulation Experiments on Semiconductor Manufacturing Datasets
#### 4.2.2 Process of Simulation Experiment
For example, when the \(fall\) value is the same and the \(13^{\#}\) experiment \(\alpha=0.05\) is less than the \(14^{\#}\) experiment \(\alpha=0.1\), the number of iterations of the experiment shown in Figure 7(a up to 350) is greater than the number of iterations of the experiment shown in Figure 7(b) (more than 200). At the same time, we can see that the fluctuation range of timeliness score in Figure 7(a about \(0.93-1.04\)) is smaller than that in Figure 7(b  
Figure 6: The trend of timeliness score converging to 0. Figure 7: The fluctuation amplitude of timeliness score is different under the two parameters. In order to test the operation effect of the model considering multiple attributes (such as temperature, humidity, pressure, flow, etc. ), we divided the original data set into four. According to Formulas (8) and (9), we carried out simulation experiments \(15^{\#}\). The experimental \(15^{\#}\) results are shown in Figure 8.  
In Figure 8, we consider four attributes: temperature, humidity, pressure and flow. Finally, the model converges because the timeliness score of the humidity attribute reaches 0. We can choose the appropriate \(\alpha\) value according to the requirements of different properties of products on the sensitivity of abnormal monitoring, so that the production process can be dynamically adjusted.
## 3 Initial State of SBSs Based on Relaxed Threshold for LSTM Traffic Prediction  
When using the SBS traffic prediction algorithm to study the switching state of the SBS, one generally sets a traffic threshold, where the predicted traffic load of the SBS in the next period is lower than the threshold and is turned off, and vice versa. In addition to the accuracy of the prediction algorithm, the setting of the threshold value is also important. A fixed threshold value set artificially too high will turn off the SBS too much, reducing the quality of service for users or even making them unserved, and a threshold value set too low will result in poor energy saving. This paper corrects the results of SBS switching by subsequent SBS state switching cost and user association algorithms to ensure that unreasonable turn-on or turn-off does not occur, so we can set a higher threshold for SBS turn-on traffic and a lower threshold for SBS sleep traffic, which is then supplemented by subsequent algorithms to make it possible to turn off the SBS to the maximum extent without affecting user service.
## Materials and Methods
### Satellite Imagery
#### 2.2.1 PlanetScope  
PlanetScope image products are available in three different forms. PlanetScope Basic Scene (1B) is a product with radiometric and sensor corrections only, which is designed for users with advanced knowledge of image processing. PlanetScope Ortho Scene (3B) is an orthorectified product that is projected to a cartographic projection. PlanetScope Ortho Tile (3A) products are orthorectified as individual 25 km \(\times\) 25 km tiles, and can serve a wide range of applications that need accurate geolocation and cartographic projection. PlanetScope satellite imagery is state-of-the-art optical products with up to 3-m spatial resolution. Unlike other optical satellites, the PlanetScope satellite constellation consists of multiple launches of groups of individual satellites (also called \"Doves\") with continuous improvements of on-orbit capacity. The complete PlanetScope constellation of about 175 satellites (by 2 April 2018) covers the entire earth's landmass every day, and has a daily collection capacity of about 300 million km\({}^{2}\). PlanetScope Ortho Tile images of the study sites were downloaded from the Planet Explorer Beta website in June 2017. Only images with cloud cover \(<\)50% and images acquired between January-May 2017 were used. On average, 13.0 images were available for each location. The minimum number of images per location was four, and the maximum was 24.
# A Printed Wearable Dual-Band Antenna for Wireless Power Transfer
## 2 Design and Fabrication  
It is important to choose a substrate material that is tested under bending conditions [26]. Bending, twisting, and rolling tests of the fabricated antenna prototypes presented in [27] show that Kapton is a robust material for designing wearable antenna. Kapton is prone to performance degradation because it resists substrate deformation. In this work, the flexible antenna was designed to be printed on Kapton. We chose Kapton because it has physical robustness, high flexibility, very high durability, high mechanical strength, distortion resistance to harsh environments, thus, enhancing the reliability of the antenna [4; 28].  
The printing material and equipment are described as follows [33]:  
_PCB Printer, Voltera V-One:_ Voltera V-One shown in Figure 1 was used to fabricate the antenna. The Gerber file of the antenna design was first imported to V-one software. After calibrating ink and position, the device was set to dispense ink and solder paste onto the substrates.  
_Conductive Ink:_ The conductive ink from Voltera was used for printing transmitting antenna on the FR-4. After thermal curing the ink the antenna is ready for testing.  
Figure 1: V-one from Voltera was used for fabrication.  
Flexible Conductive InkFor the flexible substrate, the flexible conductive ink (from Voltera) that is compatible with Kapton (polyimide), polycarbonate, PET was used. This specific ink has a curing temperature of 140 \({}^{\circ}\)C for 10 min or 120 \({}^{\circ}\)C for 30 min.  
The proposed microstrip antenna design is based on split-ring elements and can be used at two frequencies (2.5 GHz/4.5 GHz). The dimension of the transmitter (TX) and receiver (RX) antennas are 14 mm \(\times\) 15 mm, occupying a small area.  
In this design, a current-probe feeds the outer ring, and the inner ring is considered to provide frequency tuning. The design procedure is presented in [34]. To verify the design, antennas were simulated by ANSYS HFSS (High Frequency Structure Simulator) software [35]. Simulation results were compared with empirical ones. Figure 2 illustrates the proposed antenna. While the overall design of the TX and RX antennas is the same, the substrate materials and thicknesses are different. A rigid substrate (FR-4) with a thickness of 1.56 mm, relative permittivity of 3.66 and dielectric loss tangent of 0.004 was used for the TX. A flexible substrate (Kapton) with a thickness of 0.17 mm, relative permittivity of 3.4 and conductivity of 0.00524 \(\frac{S}{m}\) was used for the RX. Since the substrate materials and thicknesses are different, that resonance frequencies of the TX and RX are not exactly the same. The antennas were simulated in the air and on the muscle tissue. The muscle tissue was assumed to have the relative permittivity of 49.54, and the conductivity of 4.0448 \(\frac{S}{m}\) obtained from the Institute of Applied Physics (IFAC) database [36].
## 1 Introduction
The antennas compared are Regular Palm Tree-Coplanar Vivaldi Antenna (RPT-CVA), Front Cut Palm Tree (FCPT-CVA), Middle Cut Palm Tree (MCPT-CVA), Back Cut Palm Tree (BCPT-CVA), Complete Cut Palm Tree (CCPT-CVA), Left Tilt Palm Tree (LTPT-CVA), Right Tilt Palm Tree (RTPT-CVA), Hilbert Fractal Structure Palm Tree (HFSPT-CVA), Koch Fractal Structure Palm Tree (KFSPT-CVA), Exponential Slot Edge Palm Tree (ESEPT-CVA), Vertical Wave Structure Palm Tree (VWPT-CVA), Horizontal Wave Structure Palm Tree (HWPT-CVA), Regular Lens Palm Tree (RLPT-CVA), Elips Lens Palm Tree (ELPT-CVA) and Metamaterial Lens Palm Tree (MLPT-CVA). This paper is organized as follows: Section 2 discusses antenna design, Section 3 discussesResults and Discussion, Section 4 discusses Measurement and comparison of related antenna, and Section 5 conclusion.
# Point-Line-Aware Heterogeneous Graph Attention Network for Visual SLAM System
## 4 Experiments and Evaluation
### Real Data Evaluation  
As shown in Figure 11, the feasibility of the algorithm was verified on a physical and virtual oil and gas station, where the virtual simulation platform with a quadruped robot was built with Unity3D.  
To show the effects of point and line features on the SLAM system, we intercepted two frames of images for extracting the features by PL-Net and matching by HAGNN. As shown in Figure 12, it can be seen that the combination of point and line could make the SLAM algorithm obtain richer and more diverse feature information.  
The virtual simulation platform used a quadruped robot to inspect the oil field equipment. As shown in Figure 13, this trajectory was compared with the ground truth by using the evaluation package to obtain the RPE and APE. It can be seen that the area with a larger error was basically distributed at the corner of the trajectory. The RMSE was 17.5 m. Overall, the trajectory of our method was consistent with the ground truth with a high accuracy.  
Figure 11: The experimental robot platform. (**a**) The physical experimental robot platform with robot hardware including a camera, depth camera, and IMU. An additional GPS/RTK was used for the ground-truth estimation. (**b**) The virtual simulation platform.  
Figure 10: Comparison of the statistical error property between our system and ORB-SLAM2 on sequence 09 of KITTI. (**a**) Quantitative index chart of ATE. (**b**) Histogram of ATE.
# Accurate and Detailed Transversal Road Section Characteristics Extraction Using Laser Scanner
## 1 Introduction
Other approaches to achieving higher levels of robustness in the detection of road lines are raised in [30]. Similarly, with similar equipment, [31] proposes algorithms for the detection of road boundaries. The authors of [32] propose a system that is based on a formulation of stereo with homography as a maximum a posteriori (MAP) problem in a Markov random field (MRF). This solution, that uses computer vision, provides quite robust results even in complex scenarios. In [33], the free road surface ahead of the ego-vehicle using an onboard camera is detected. The main contribution is the use of a shadow-invariant feature space combined with a model-based classifier. The model is built online to improve the adaptability of the algorithm to the current lighting, and to the presence of other vehicles in the scene. In other cases, the fusion of laser scanners and computer vision is used, as in [34], where the algorithm is based on clouds of 3D points and is evaluated using a 3D information from a pair of stereo cameras, and also from the laser scanner. To obtain a dense point cloud, the scanner cloud has been increased using Iterative Closest Point (ICP) with the previous scans. Algorithms proposed in this paper are oriented for the positioning of the vehicle in the road with centimetric precision, even when the signals obtained from GNSS or inertial systems are not appropriate. The solution is based on the use of 3D laser scanner, and the algorithms pursue the detection of the boundaries of the road and the lanes, identifying the lane through which it circulates, and the lateral position (and, therefore, the identification of lane change maneuvers). Unlike previous approaches, the algorithm proposed in this paper tries to increase the robustness of the results with a low computational cost (much faster than real time), using only laser scanner data and a digital map when available, even in complex scenarios, and to go through the detection of road boundaries and, subsequently, the detection of lanes in an integrated way, taking advantage of both results to increase global reliability and to improve partial approaches. The algorithm also accept the input of digital map information in order to improve results, but this additional information is not strictly necessary. Furthermore, the algorithms should work under different scenarios, rural and urban, considering that the road boundaries and the configurations of the lane lines could vary.
# Analysis and Experimental Validation of Efficient Coded OFDM for an Impulsive Noise Environment
## 4 Experimental Planning and Test Bed Design
### Measurements Scenarios
#### 4.2.2 Experimental Scenario 2  
The second experimental scenario consists of NLOS situations. It is very similar to the first case except for one detail. We use a metallic reflector as depicted in Figure 4(b) to generate multi-path phenomena.  
* We consider 2 m between the two USRPs. The emitter and the receiver are at 1 m from the source.
* The second scenario consists of placing the receiver at 1.80 m from the source and the emitter at 1.90 m.  
As for the LOS experiments, we evaluated four types of voltage varying from 12 kV-18 kV.
# Enhanced Efficient EMT-Type Model of the MMCs Based on Arm Equivalence
## 3 Equivalent Circuit of the MMC
### Average Capacitor Current of the SMs  
The positive direction of the currents and voltages are shown in Figure 1a. As shown in Figure 1b, when the SM is under inserted mode, through the switching actions of power devices, the arm current is diverted into the capacitor branch of the SM. The current flowing through the capacitor is defined as the capacitor current. The capacitor current of the \(x\)th SM on the \(r\) arm in phase \(j\)\(i_{C}\), \(r_{j\_x}\) is equal to the current flowing through the \(r\) arm in phase \(j\)\(i_{\text{Arm, }rj}\). Namely, \(i_{C}\), \(r_{j\_x}=i_{\text{Arm, }rj}\). In contrast, \(i_{C}\), \(r_{j\_x}\) is equal to zero for bypassed mode. Each SM is under only one mode at a specific moment. For the sake of convenience, \(i_{C}\), \(r_{j\_x}\) is expressed as:  
\[i_{C,rj\_x}=S_{rj\_x}i_{\text{Arm,}rj} \tag{9}\]  
where, \(i_{\text{Arm, }rj}\) is the current flowing through the \(r\) arm in phase \(j\); \(S_{rj\_x}\) represents the switching function of the \(x\)th SM on the \(r\) arm in phase \(j\), and is defined as:  
\[S_{rj\_x}=\left\{\begin{array}{c}1,\text{\emph{inserted} mode }(T_{1} =1,\,T_{2}=0)\\ 0,\text{\emph{ bypassed} mode }(T_{1} =0,\,T_{2}=1)\end{array}\right. \tag{10}\]  
Sum up the capacitor current of all \(N\) SMs on the specific arm, then:  
\[\sum_{x=1}^{N}i_{C,rj\_x}=\sum_{x=1}^{N}S_{rj\_x}i_{\text{Arm,}rj} \tag{11}\]  
so  
\[\frac{1}{N}\sum_{x=1}^{N}i_{C,rj\_x}=i_{\text{Arm,}rj}\frac{1}{N}\sum_{x=1}^{ N}S_{rj\_x} \tag{12}\]  
Figure 4: The average value model (AVM) topology.  
As the number of SMs per arm \(N\) is very large, and the switching frequency is high enough, the inserted mode and bypassed mode for each SM are switching frequently. Therefore, the definition of the ASF is applied to represent the characteristic of SM frequent switching actions to simplify the analysis. For the sake of simplicity, the ASF is defined as \(S_{rj}\) to denote the average insertion ratio of the SMs on the \(r\) arm in phase \(j\), and is expressed as [16; 26]:  
\[S_{rj}=\frac{1}{N}\sum_{x=1}^{N}S_{rj\_x} \tag{13}\]  
In order to maintain the DC voltage \(V_{\text{dc}}\) stable, the sum of \(S_{\text{pj}}\) and \(S_{\text{nj}}\) in phase \(j\) is controlled as 1. The average capacitor current of the SMs on the \(r\) arm in phase \(j\)\(i_{\text{C},\gamma}\) is defined as:  
\[i_{\text{C},rj}=\frac{1}{N}\sum_{x=1}^{N}i_{\text{C},rj\_x} \tag{14}\]  
Note that, the sums of the currents in Equations (11) and (14) do not express the connection of SMs in parallel, but express the concept of SM average switching actions. From Equations (12) and (13), Equations (11) is rewritten as:  
\[i_{\text{C},rj}=S_{rj}i_{\text{Arm},rj} \tag{15}\]
## 5 Simulation Results  
### Simulation  
In this section, we design a practical LDPC coded modulation system based on the PS scheme. The system block diagram is shown in Figure 2. At the transmitter, in order to generate the 16-ary PS-QAM symbols, the pseudo-random binary sequence (PRBS) is generated. Therefore, we can see that the uniform distribution binary sequence is divided into two parts, one of which is fed to the CCDM. The CCDM converts the uniformly distributed bits into the desired distributed 16-ary QAM symbols. After binary converting, they are encoded together with the remaining binary bits. We utilize the DVB-S2 LDPC code, whose code rate is \(\frac{2}{3}\). At the receiver, the LLRs are calculated for bit-metric decoding. We then evaluate the achievable information rate of the signal. We also measure the average SER and the post-FEC BER.
# Lifetime Prediction of Single Crystal Nickel-Based Superalloys
## 2 Experimental Procedure and Methodology
### Lifetime Assessment
#### 2.3.6 ANN Model Configuration  
ANNs are made up of 20 hidden layers with 20 neurons and a single output layer and neuron to predict the lifetime. The stochastic gradient descent optimizer \"Adam\" is used since it adjusts its learning rate with a corresponding decrease in the loss function, and the initial learning rate is set to 0.0001.  
Loss function and metric are chosen as Mean Square Error (MSE) and Root Mean Square Error (RMSE), respectively. The training data, formed with the damage model, is consistent and does not contain data points that differ significantly from others, making MSE a suitable loss function for this case. Stress-lifetime values fed into the ANNs are on a logarithmic scale, eliminating the need for a logarithmic error. This yields better training results rather than using actual lifetime values with mean squared logarithmic error (MSLE). Lifetime data ranges from 1 to 10\({}^{10}\), and it is normalized before being fed into the input layer. Logarithmic scaling decreases the difference between maximum and minimum lifetime values, thus making it easier for ANNs to compute the nonlinear relation.  
Figure 5: Finite element mesh (**a**) and the boundary conditions (**b**) of the notched specimen.  
\[\text{Loss (MSE)} =\frac{1}{n}\sum_{i=1}^{n}(y_{i}-\hat{y}_{i})^{2}\] \[\text{Metric (RMSE)} =\sqrt{\frac{1}{n}\sum_{i=1}^{n}(y_{i}-\hat{y}_{i})^{2}} \tag{22}\]  
The dataset is divided into 70% for training, 15% for validation, and 15% for an independent test set. During training, the validation set is used to monitor performance by tracking validation loss and metrics, ensuring the model does not overfit. After training, the independent test set, unseen during training and validation, is evaluated to assess the model's generalization and predictive accuracy on unseen data.
# Design and Implementation of C-Band Large-Power Planar Butler Matrix in SRS
## 2 Principle and Design Method
### Design and Analysis
#### 2.3.4 Butler Matrix Design  
The Butler matrix was designed as an eight-port device. The input ports are labeled P1 to P4, and the output P5 to P8. The rest of the details of the design are chamfered edges, ventilation holes, square coaxial line corners for corner-cutting, square coaxial line corners for rounding, avoiding low-pressure discharge, etc. These design factors were considered to achieve high power threshold.  
Aluminum alloy is used to build both inner and outer conductors. The material used in the simulation of Butler matrix is aluminum, and the actual machining is performed with aluminum alloy in order to machine the material more rigidly. One significant detail is that each of the eight ports of the Butler matrix leads to a small cylinder in order to facilitate testing with the L29 connector. The cylinder size is 2 mm in diameter and 4 mm in height. The proposed Butler matrix [28] uses a planar open-cover structure, as shown in Figures 14 and 15. The mounting configuration ensures the strength of the structure. It is 440 mm by 400 mm and has a height of 40 mm.  
Figure 13: Simulation results of 0\({}^{\circ}\) phase shifter (**a**) S-parameters; (**b**) phase difference.