esa-sceva/satcom-chunk-collection huggingface dataset:
## 6 Experiments
### Partial Experiments
#### 6.1.1 Training-Based RSSI Localization
The RSSI measurements were assumed with a realist noise level. Then, we executed the training and application stages of the method and registered the localization errors. The mean localization error assuming no misplacement was 128 cm and the standard deviation was 73 cm, due to the noise assumed in the RSSI measurements. The results in Figure 9 show that the localization mean error and its standard deviation behave fairly well with misplacement errors. When the standard deviation of the misplacement errors increases from 0 to 500 cm, the mean error only increases from 128 to 407 cm and its standard deviation increases from 73 to 196 cm, which illustrates the good behaviour of the proposed method with misplacement of anchor nodes. Figure 8: \(Cont.\)  
Figure 9: Impact of anchor nodes misplacement in mean localization error (**left**) and standard deviation (**right**). Performance During the Training Stage  
As pointed out in Section 4.2.1, the RSSI-range model can be estimated using measurements from only two static nodes. Once an initial model has been computed, it can be applied to localize mobile nodes. Thus, the training stage can be simultaneous with the application stage. Each static node keeps receiving new training measurements and as soon as it re-calculates a new model, it can be used in the application stage. At the beginning, RSSI-range models computed with few measurements will not achieve high localization accuracy. With more measurements, the trained models will be more and more precise, resulting in higher accuracy. The objective of these experiments is to evaluate the evolution of the localization accuracy during this process. The experiments were carried out as follows. Robots carrying a node followed their trajectory in the environment. At a certain time, both the training stage and the operation stage started at the same time. As soon as a static node had gathered enough RSSI measurements, it built its own RSSI-range model. As the number of RSSI measurements gathered increased, the node recalculated its model. Meanwhile, mobile nodes broadcasted _LocRequest_ packets. If a static node received a _LocRequest_ packet but still had not built its RSSI-range model, it ignored the packet. Only static nodes that had their own RSSI-range model responded. With the responses, mobile nodes estimated their location. In this experiment, the localization method was applied using only the measurements--and the RSSI-range models--from four static nodes. The objective is to evaluate the impact of the accuracy of these four RSSI-range models on the localization errors. First, the impact of the number of static nodes considered in the training was evaluated. Each static node contributed with 200 measurements to the training set
## Materials and Methods
### Plant Sampling and TE Analysis  
At harvest, during the flowering stage, the base of the aerial part of the plants was cut with a hand pruner. Per area, ten plants were randomly sampled simultaneously to the sediments. After the harvest, all of the aerial biomass was weighed (portable hand scale) to obtain the yield per area. The plant samples were transported to the laboratory for further analyses. _M. sylvestris_ shoots are composed of three parts (the flower, the stem, and the leaf), which were manually separated and weighed for each plant sample to obtain the fresh weight (FW). The separated plant parts were washed with tap and deionized water and were dried until constant weight (40 \({}^{\circ}\)C). An additional weighing was performed on the dry sample (DW, dry weight), and each sample was ground with a blender to obtain a powder. Per plant, on each part (flower, stem, leaf), digestion (microwave digester Mars Xpress CEM) was performed with 0.5 g of DW with 10 mL of HNO\({}_{3}\) (69%). The solution that was obtained was completed with Milli-Q water until 50 mL was reached, and the solution was filtered (0.45 \(\upmu\)m, hydrophilic Teflon). The TE concentrations in the eluates were measured by ICP-OES (Agilent 5100) or ICP-MS (Agilent 7500). One standard reference material was used for analytical quality control (Branches and leaves of Bush \"NCS DC 73349\", NCS Testing Technology, China, [[http://www.ncsstandard.com](http://www.ncsstandard.com)]([http://www.ncsstandard.com](http://www.ncsstandard.com)), accessed on 5 June 2018). For all of the digestion sets, recoveries of the reference material were between 0.96 and 0.99 for Cu, 1.03 and 1.05 for Pb, and 1.03 for Zn in the branches and leaves. The reference value for Cd was lower than the analytical LoQ. In 2020, to obtain the control TE concentrations in _M. sylvestris_ on uncontaminated soil, 1 m\({}^{2}\) of _M. sylvestris_ was sown in a private garden (50\({}^{\circ}\)25\({}^{\prime}\)43.5\({}^{\prime\prime}\) N, 3\({}^{\circ}\)33\({}^{\prime}\)16.5\({}^{\prime\prime}\) E) near the experimental site, and three shoots of mallow were harvested. Due to the low quantity of flowers that was obtained, flowers from uncontaminated soil were pooled and considered as a single sample. This additional experiment yielded three samples of mallow shoots and one flower sample of uncontaminated origins. These samples were characterized following the same protocols as those described for the contaminated samples. The TE concentration in the shoots was calculated according to the equation:  
[TE] shoots = ([TE] flower * DW of flower + [TE] stem * DW of stem + [TE] leaf * DW of leaf)/(DW of flower + DW of stem + DW of leaf)  
Using the TE concentrations in the shoots and the total and extractable concentrations in the sediment, the bioconcentration factor (BCF) [40] was calculated as follows:  
1. BCF ext = [TE] shoots/[TE] sediment extractable
2. BCF tot = [TE] shoots/[TE] sediment total
# Mechanically Reconfigurable, Beam-Scanning Reflectarray and Transmitarray Antennas: A Review
## 4 Feed Movement
### Feed Displacement on Fully Illuminated Apertures  
Beam scanning with antenna arrays using feed displacement have been extensively studied in [5; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57] for RAs and in [58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69] for TAs. By convention, in fully illuminated RAs, the amplitude of the feed illumination at the aperture rim is less than \(-10\) dB.
## 4 Discussion of FE Analysis Results
Consequently, the normalized critical axial force decreases, especially when lateral bracing is weak. The influence of arch rib spacing is taken into account in all three codes. Figure 13 shows that the decreasing stiffness of lateral bracing for bridges with the same arch ribs will lead to a decrease in the normalized critical axial force. On the contrary, the normalized critical axial force tends to augment with falling arch rib stiffness when the lateral bracing is the same. The normalized critical axial force basically decreases with increasing stiffness ratio when the stiffness of the arch ribs and lateral bracing are simultaneously taken into account. In addition, as shown in Figure 13c, a smaller \(\gamma\)-value relating to the lateral bracing significantly reduces the normalized critical axial force. The Chinese and European codes consider the stiffness of both arch ribs and lateral bracing. The Japanese code considers the stiffness of the arch ribs, but parameters such as the arrangement of lateral bracing and the \(\gamma\)-value are not taken into consideration. Therefore, it can be anticipated that the out-of-plane critical axial force calculated with the Japanese code will not be conservative when the stiffness ratio is large or the \(\gamma\)-value is small [31,32]. Figure 13 demonstrates that compared with the other two types of steel arch bridges, the normalized critical axial force of a half-through type arch bridge is mostly smaller when the stiffness ratio is relatively small, while otherwise, it is similar to that of a through-type  
Figure 13: Influence of Parameters on Normalized Critical Axial Forces by FE Analysis: (**a**) Influence of Rise-to-span; (**b**) Influence of Arch Rib Spacing; (**c**) Influence \(\gamma\)-value; (**d**) Influence of Bridge Type. bridge. Since the girder framework of a half-through arch bridge is rigidly connected to the place near the arch springing, any deformation of the girder intensifies the lateral displacement of the arch ribs, which reduces their critical axial force. Moreover, the normalized critical axial force of a deck-type bridge is larger than that of a through-type bridge when the stiffness ratio is relatively large; otherwise, the normalized critical axial force of a through-type bridge is larger than that of a deck-type bridge. This is because the girder framework of a deck-type bridge has a certain positive effect on enhancing the out-of-plane stability, and the effect is more obvious when the stiffness ratio is relatively large. The type of bridge is considered in the Japanese and European codes but not in the Chinese code.
# Special Issue on HVDC for Grid Services in Electric Power Systems
## 3 HVDC Protection Strategy in Contingency Cases  
### A Novel Overcurrent Suppression Strategy during Reclosing Process of MMC-HVDC [5]  
This paper discusses a strategy to control the overcurrent that can occur in the post-fault process of mesh current method (MMC)-HVDC. A MCM is proposed for accurate overcurrent calculation of a loop MMC-HVDC grid, and a reclosing current limiting resistance (RCLR) is calculated using the result.  
Assessment of Appropriate MMC Topology Considering DC Fault Handling Performance of Fault Protection Devices [6]  
This paper compared DC fault handling performance in variable fault location on a DC line. The simulation result confirmed that Half Bridge-MMC with a hybrid circuit breaker (HCB) is superior than FB-MMC with a residual circuit breaker (RCB) due to low fault current, low interruption time, low overvoltage magnitude and faster recovery.  
A Study on Stability Control of Grid Connected DC Distribution System Based on Second Order Generalized Integrator-Frequency Locked Loop (SOGI-FLL) [7]  
This paper proposes advanced control method using Second Order Generalized Integrator-Frequency Locked Loop (SOGI-FLL) that can be applied to a 3-phase AC/DC PWM converter for DC distribution. The proposed control scheme improves transient characteristics of DC distribution systems.
# Data Fusion Based on Adaptive Interacting Multiple Model for GPS/INS Integrated Navigation System
## 3 System Architecture
### Interacting Multiple Model Filter Structure
#### 3.1.2 Mode Probability Update  
Applying the original mixed state estimate and covariance of preliminary procedure, the likelihood of KF prediction and update for each filter is obtained, and the state mean and covariance of each filter can be estimated accordingly. Furthermore, the function of likelihood which stems from every filter can be simplified as  
\[\Lambda_{m}^{i}=\frac{1}{\left(2\pi\right)^{n/2}\left|S_{m}^{i}\right|^{1/2}} \exp\left(-\left(v_{m}^{i}\right)^{T}\left(S_{m}^{i}\right)^{-1}v_{m}^{i}/2\right) \tag{12}\]  
in which \(n\) represents the frequency of measurements in this step; \(v_{m}^{i}\) and \(S_{m}^{i}\) are the innovation sequence and its corresponding covariance, respectively, which are calculated as  
\[v_{m}=z_{m}-H_{m}x_{m}^{-} \tag{13}\]  
\[S_{m}=H_{m}P_{m}^{-}H_{m}^{T}+R_{m} \tag{14}\]  
The updated probability of each filter can be written as  
\[\mu_{m}^{i}=\frac{1}{c}\Lambda_{m}^{i}\overline{c}_{i} \tag{15}\]  
in which \(c\) indicates a normalized constant for the mode probability update, and is done as  
\[c=\sum_{i=1}^{r}\Lambda_{m}^{i}\overline{c}_{i} \tag{16}\]
# The Design of an Energy Harvesting Wireless Sensor Node for Tracking Pink Iguanas
## 3 Device Design
### Electronics Design  
Figure 2 shows board layout and components placement. The operations of the sensor node are the following: (i) acquisition GPS position and (ii) retrieval of sensors values, (iii) storing all information and (iv) data transmission through the gateway. The fulfillment of these functions relies on the following electronic components:  
1. CC1310 wireless controller [10], an ultra-low-power device from Texas Instrument with a low active RF and MCU current consumption and flexible low-power modes. It provides excellent battery life and allows long-range operation. It integrates a powerful 48-MHz Arm Cortex-M3 micro controller, a dedicated Radio Controller and a ultra low power Cortex M0 sensor controller.
2. Sensor set including an accelerometer (ADXL345 [11]), a digital humidity sensor with integrated temperature sensor (HDC1008 [12]) and a UV light sensor (VEML6070 [13]);
3. Global TOP PA6C GPS receiver based on MediaTek MT3329 chipset and an integrated ceramic antenna. It is characterized by a larger receiver sensitivity (\(-165\) dBm thanks to the TCXO Design) resulting in an high position accuracy.
4. NOR flash memory storage with a capacity of 1 GB (MT25 QL256 ABA8E12).
5. Skyworks SE2435L [14]. This is a high performance RF front-end module operating in the 860-930 MHz frequency band that includes a power amplifier for transmission and a Low Noise Amplifier for reception.  
Figure 1: Map of the monitoring field.  
The overall node architecture is shown in Figure 3. All the functions are coordinated by the CC1310 controller that implements the node logic. The GPS receiver provides the position of the node; it communicates with the controller through a UART interface. The sensor set delivers data to the controller by a I2C interface. Finally, a SPI interface accesses to the flash storage memory. The CC1310 integrates a wireless modem that directly generates and receives RF signals. To improve the node communication range, all the signals go through the Skyworks RF front-end module and a band-pass filter.  
The device integrates solar panels and super-capacitors (for energy storage) as key enabler to an almost perpetual operations of the wireless sensor node. To this regard, the DC-DC conversion can operate from the range of nanowatts, in deep sleep mode, up to Watts in the long range transmission mode (the SE2435L absorbs 250 mA with 23 dB of gain). Moreover, the CC1310 implements the Wake-on Radio technology. This feature embeds a low power receiving mode that can enable the discovery functionality of the devices while in sleep mode [15].
# Electrophysical Properties of PZT-Type Ceramics Obtained by Two Sintering Methods
###### Abstract  
This study demonstrates the impact of two sintering techniques on the fundamental properties of doped PZT-type ceramic materials (with Mn\({}^{44}\), Sb\({}^{3+}\), Gd\({}^{3+}\), and W\({}^{6+}\)), with the general chemical formula Pb(Zr\({}_{0.49}\)Ti\({}_{0.51}\))\({}_{0.94}\)Mn\({}_{0.021}\)Sb\({}_{0.016}\)Gd\({}_{0.012}\)W\({}_{0.012}\)O\({}_{3}\). The synthesis of ceramic powders was carried out through the calcination method. Two different methods were used in the final sintering process: (i) pressureless sintering (PS) and (ii) hot pressing (HP). The PZT-type ceramics were subjected to electrophysical measurements, encompassing various analyses such as X-ray diffraction (XRD), microstructure (scanning electron microscopy (SEM)), ferroelectric and dielectric properties, and DC electrical conductivity. The analysis of the crystal structure at room temperature showed that the material belongs to the perovskite structure from the tetragonal phase (P4\(mm\) space group) without foreign phases. Both sintering methods ensure obtaining the material with appropriate dielectric and ferroelectric parameters, and the tests carried out verified that the ceramic materials have a diverse range of parameters appropriate for use in micromechatronic and microelectronic applications. The obtained ceramic material has high permittivity values, low dielectric loss tangent values, and high resistance. At room temperature, the ceramic samples' \(P\)-\(E\) hysteresis loops do not saturate at a field of 3.5 kV/mm (\(P_{\mathrm{m}}\) maximum polarization is in the range from 12.24 to 13.47 \(\mathrm{\SIUnitSymbolMicro c}\)/cm\({}^{2}\)). However, at higher temperatures, the \(P\)-\(E\) hysteresis loops become highly saturated, and, at 110 \(\mathrm{\SIUnitSymbolCelsius}\), the \(P_{\mathrm{m}}\) maximum polarization values are in the range from 28.02 to 30.83 \(\mathrm{\SIUnitSymbolMicro c}\)/cm\({}^{2}\).  
piezoceramics; PZT-type material; sintering; hot pressing; dielectric properties +
Footnote †: journal:
###### Abstract  
The visual search performance of radiologists is systematically challenged due to the use of flat-panel displays when viewing multi-slice images. Three-dimensional visualization of information is expected to facilitate visual search for radiologists. However, as the differences in user performance, depending on radiologist experience, have not yet been assessed for real three-dimensional images, it is difficult to estimate the usability of new visualization systems for radiologists with different amounts of professional search experience. In this study, we aimed to determine how three-dimensional visual search is affected by radiologist experience and the physical properties of stimuli. Radiologists, residents, and medical students accomplished visual search tasks with varying set sizes and target-distractor similarities. Search items were presented on multiple display planes and image manipulation was conducted using a computer keyboard. We compared the search outcome and strategy among three groups of participants. All three groups submitted a similar number of correct responses depending on target-distractor similarity. However, in contrast to radiologists and residents, it took a considerably longer time for students to find the targets. The major differences were evident in search strategy when comparing the image manipulations of radiologists with those of residents and students. Our results demonstrated that experienced radiologists' search performance benefited from seeing the entire three-dimensional view of an image, whereas residents and students focused instead on reducing the amount of information and searched in a selective manner. These findings should be taken into account when planning the implementation of new workstations with three-dimensional visualization in radiology.  
Keywords:visual search; three-dimensional image; radiologists; user performance; image manipulation; search strategy +
Footnote †: journal: Applied Sciences
# Comparison of GPM IMERG and TRMM 3B43 Products over Cyprus
## Data and Methodology
### TRMM Data  
The Tropical Rainfall Measuring Mission (TRMM), launched by NASA (National Aeronautics and Space Administration) and JAXA (Japan Aerospace Exploration Agency) in 1997, provided precipitation estimates within the latitude 50\({}^{\circ}\) S to 50\({}^{\circ}\) N (see [40; 41]).  
The TRMM satellite carried several instruments to detect precipitation, including the Visible Infrared Radiometer (VIRS), TRMM Microwave Imager (TMI), Cloud and Earth Radiant Energy Sensor (CERES), Lightning Imaging Sensor (LIS) and the first spaceborne precipitation radar (PR). Several precipitation retrieval algorithms have been developed based on observations from the sensors on board the TRMM satellite such as the TMPA (TRMM Multi-satellite Precipitation Analysis). The TMPA algorithm combines observations from satellite-based microwave and infrared sensors and ground rainfall gauge analyses, and produces 3-hourly rainfall estimates at a spatial resolution of \(0.25^{\circ}\times 0.25^{\circ}\) with a quasi-global coverage (50\({}^{\circ}\) N-S) [42]. In 2015, the TRMM mission came to an end, with the instruments turned off and the spacecraft re-entering the Earth's atmosphere. However, the multi-satellite TMPA products continue to be produced using input data from other satellites in the constellation. Indeed, the TMPA algorithms are still being run using other calibrators to produce data in parallel with GPM IMERG [43].  
The Level 3 TRMM 3B43 data, also called TMPA product, were chosen for our analysis [42]. In particular, TRMM 3B43 (v7) data for the period from April 2014 to June 2018 were used.
# Current-Assisted Single Photon Avalanche Diode (CASPAD) Fabricated in 350 nm Conventional CMOS
## 3 Results and Discussion
### Timing Jitter  
Timing jitter of photon-detection in a conventional SPAD is due to the statistical variation on the avalanche process and is in the order of tens to hundreds of picoseconds. However, in CASPAD, the timing jitter is due to the sum of the statistical variation in the avalanche process and the variable time it takes for the photo-generated electrons to travel to the central avalanching region. In [14], the position dependent delay has been characterized in more detail. For characterizing the timing jitter, a pulsed fiber laser, with a wavelength of 785 nm, is used which has a pulse width of \(\sim\)70 ps. The laser spot is aligned on the whole device area with a custom microscope. Figure 5b shows the timing jitter of the device measured with a Becker and Hickel SPC-130 photon counting card. The timing jitter is characterized by the full-width half-maximum (FWHM) which is \(\sim\)370 ps. A small diffusion tail (\(<\)1%)  
Figure 5: **(a)** Measured dark count rate with respect to the excess bias voltage. **(b)** Timing jitter full-width half-maximum (FWHM) = 370 ps (V\({}_{\text{ex}}\) = 0.86 V). **(c)** Measured interavalanche times to characterize afterpulsing (V\({}_{\text{ex}}\) = 0.86 V) with an exponential fit **(d)** Measured photon detection probability with respect to the excess bias voltage at a wavelength of 785 nm.  
can also be observed, most likely due to the slowly diffusing carriers which are generated deeply in the substrate below the epi layer.
## 7 Conclusions  
The control strategy presented in this work allows us to balance the energy of the converter arms by means of circulating ac and dc currents. The ac currents circulate only inside the converter not being reflected in the input or output of the topology. The ac current flow through \(T_{2}\)-structure is the same that in \(T_{1}\)-structure, this allows us to obtain an input current with minimum harmonic content. Moreover, due to the control strategy, the output voltage has also a very low ripple. These characteristics are fundamental in HVdc systems since they are not designed to manage ac variables.  
On the other hand, the sensitivity analysis shows that small variations of the converter parameters do not affect the performance of the control system.  
The decoupling of the control allows us to reduce the impact of power changes on the output, as seen in the results. The presented topology operating with the proposed control strategy exhibits no common-mode alternating voltage component, which is an advantage and validates its possible use in HVdc or MVdc systems.  
Conceptualization, C.P., J.R. and R.P.; methodology, C.P.; software, C.P. and J.R.; validation, C.P. and R.V.; formal analysis, I.A. and W.J.; investigation, I.A. and W.J.; resources, R.V. and W.J.; writing--original draft preparation, C.P. and J.R.; writing--review and editing, R.P.; visualization, W.J.; supervision, J.R.; project administration, [PERSON]; funding acquisition, R.P. and C.P. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Chilean Agency of Research and Development, grant number \"ANID FONDAP 15110019--PUENTE 1522A0006\" and \"DIUFRO Project support by Universidad de La Frontera grant number DI23-0011\".  
Figure 21: Dc-link voltage waveforms for case 6.