esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 Experiments and Results
The detection limits for H\({}_{2}\)O obtained by the QEPTAS sensor at distances of 1 m and 2 m were ~12 ppm and ~55 ppm, corresponding to a NNEA coefficients of \(8.4\times 10^{-7}\) W\(\cdot\)cm\({}^{-1}\cdot\)Hz\({}^{-1/2}\) and \(3.7\times 10^{-6}\) W\(\cdot\)cm\({}^{-1}\cdot\)Hz\({}^{-1/2}\), respectively. Compared to other photothermal spectroscopy techniques based on a silicon resonator [36] or a fiber-coupled Fabry-Perot interferometer [37], the NNEA of QEPTAS is competitive. [PERSON] et al. give a brief qualitative description of the analysis of photothermal effects [31]. The detailed theoretical analysis can be obtained from a theoretical model for resonant optothermoacoustic systems [38].
# Research on the Influence of Rectifying Orifice Plate on the Airflow Uniformity of Exhaust Hood
###### Abstract  
Designing and improving collection systems for dust and toxic pollutants is crucial for improving the safety and indoor air quality of laboratory buildings. Push-pull ventilation systems with uniformly distributed parallel airflow have been proven to be of great help in this task. Designing exhaust hoods with parallel airflow distribution can effectively enhance the airflow uniformity of push-pull ventilation systems, especially when combining it with the implementation of rectifying orifice plates on the exhaust hoods. Therefore, this study combines a computational fluid dynamics (CFD) method and experimental approach to analyze the influence of key factors that lead to improvements in the airflow uniformity through the use of rectifying orifice plates, namely the aperture and porosity, as well as the number of rectifying orifice plates on the airflow uniformity of exhaust hoods. The study shows the following: (1) The aperture of the rectifying orifice plate considerably affects the airflow uniformity of the exhaust hood. Specifically, near the exhaust hood outlet, the airflow uniformity is negatively correlated with the aperture; conversely, near the exhaust hood inlet, the airflow uniformity is positively correlated with the aperture. (2) A rectifying orifice plate with a porosity of 35.43% can effectively improve the airflow uniformity of the exhaust hood. (3) Exhaust hoods with a double-layer rectifying orifice plate structure can improve airflow uniformity by approximately 40% compared to those with a single-layer structure. The above research results can guide the optimization of exhaust hood design to improve airflow uniformity, thereby effectively enhancing the capture efficiency of the push-pull ventilation system for dust and toxic pollutants and providing a safer environment for experimenters in laboratory buildings.  
exhaust hood; rectifying orifice plate; airflow uniformity; capture efficiency of dust and toxic pollutants; laboratory building ventilation
# Low-Complexity GSM Detection Based on Maximum Ratio Combining
## 5 Simulation Results and Computational Complexity Analysis
#### 5.1.2 Computational Complexity Analysis  
The computational complexity of ML, MRC-RS and MRC-MP detectors are listed in Table 3.  
Figure 4: Average number of TACs detected by MRC-RS and MRC-MP algorithms for a GSM system with \(N_{t}=32\), \(N_{r}=16\), \(M=8\) and \(N_{p}=2\).  
Figure 5: Average number of TACs detected by MRC-RS and MRC-MP algorithms for a GSM system with \(N_{t}=16\), \(N_{r}=8\), \(M=16\) and \(N_{p}=3\).  
\(N_{C}=2\)\({}^{\lfloor\log_{2}C_{N_{t}}^{N_{p}}\rfloor}\) is the number of TACs for the conventional GSM system. \(L\) is the number of TACs used in MRC-RS algorithm. \(\phi_{\beta}\) represents the total number of qualified antenna indices in the \(\beta\)-iteration of MRC-MP algorithm. \(\Phi\) is the number of TACs selected by the MRC-MP algorithm.  
Figures 6 and 7 show the comparison of the computational complexity of the proposed detectors and ML detector in two scenarios: (1) \(N_{t}=32\), \(N_{r}=16\), \(M=8\), \(N_{p}=2\) and (2) \(N_{t}=16
# A Comprehensive Review of Indoor Localization Techniques and Applications in Various Sectors
## 3 Methodology and Application of Indoor Localization in Various Fields  
In this section, we describe the methodologies and applications of indoor localization across various sectors, highlighting their transformative impact. Indoor localization technologies have significantly advanced healthcare, industry, military, and logistics by enabling precise tracking in GNSS-denied environments. In healthcare, Wi-Fi, BLE, and RFID systems ensure the real-time tracking of patients, staff, and assets, improving workflows and safety. Industries utilize UWB and RFID for high-precision asset tracking and workflow optimization in challenging environments. Military and emergency operations rely on hybrid systems like UWB and LoRa for robust and adaptive localization in critical scenarios. Retail and logistics employ Wi-Fi and BLE to enhance inventory management and customer experiences. The block diagram in Figure 6 outlines a systematic approach for selecting articles for this review on indoor localization. It begins with a broad search to establish foundational knowledge of indoor localization, followed by identifying relevant papers through an initial screening of abstracts and conclusions. Next, the process narrows down to exploring specific technologies, such as Bluetooth low energy (BLE), Wi-Fi, ultra-wideband (UWB), ZigBee, and RFID. The papers are then filtered by application areas, focusing on sectorslike medical, industrial, and military. A detailed screening and evaluation of the selected papers are conducted to assess their quality, relevance, and contributions. Finally, the most relevant and high-quality studies are finalized to form the basis of this review, ensuring a comprehensive and focused analysis of indoor localization technologies and applications. Table 2 provides a comprehensive comparison of indoor localization technologies, highlighting their motivations, measurement methods, and applications across various domains. It outlines the use of technologies like Wi-Fi, BLE, UWB, RFID, ZigBee, and hybrid models, emphasizing their effectiveness in diverse environments such as healthcare, industrial settings, and military operations. For instance, Wi-Fi-based systems leverage RSSI and triangulation for tracking in healthcare facilities, while BLE and UWB demonstrate high accuracy in industrial environments through advanced methods like trilateration and TOA. Hybrid models address critical scenarios, integrating multiple technologies to enhance robustness and adaptability in dynamic conditions. This comparative analysis showcases the versatility of indoor localization technologies and their role in enabling real-time tracking and resource management across multiple sectors. Figure 6: Workflow for article selection.
# Recent Development of High-Energy Short-Pulse Lasers with Cryogenically Cooled Yb:YAG
## 1 Introduction  
In 1965, [PERSON] obtained the first laser using Yb:YAG crystals as the gain medium using flashlamp pumping [1]. However, due to the poor match between the absorption spectrum of Yb:YAG crystal and the pump light spectrum, resulting in low laser efficiency, it has not received much attention, while Nd:YAG crystal has been fully developed due to its good physical and chemical properties. The energy, power, repetition frequency, and other indicators of solid-state lasers are rapidly improving, and they play irreplaceable roles in industrial processing, military, laser-confined nuclear fusion, and other fields [2]. With the advent of InGaAs laser diodes, Yb:YAG crystals have returned to the field of vision of researchers due to their excellent optical properties [3]. First, the absorption wavelength of Yb:YAG crystal is closer to the emission wavelength and has a lower quantum loss. In addition, it has no upper energy level conversion, which greatly reduces the thermal load, and the thermal effect is about 3 times smaller than that of Nd:YAG crystal [4]; secondly, the energy level lifetime of Yb:YAG crystal is about 4 times that of Nd:YAG crystal, which is conducive to storing more energy [5]; thirdly, compared with Nd\({}^{3+}\), Yb\({}^{3+}\) and YAG lattice match better, which can achieve higher doping concentration. The crystal quality is good, and the defects are few [2]; finally, the absorption bandwidth of Yb:YAG crystal at 940 nm is about 18 nm, which is much larger than the absorption bandwidth of Nd:YAG crystal at 808 nm, which is about 2 nm. Therefore, the requirements for the linewidth and wavelength stability of the diode pump source are greatly reduced [6,7]. All in all, Yb:YAG crystal is more suitable as a gain medium for high-power lasers.  
In this paper, first, changes in the properties of Yb:YAG crystal with temperature are analyzed, as well as the reason why Yb:YAG crystals, as a gain medium of high-powerlasers, need to operate at low temperatures, and a method to suppress the aggravation of ASE effect caused by low-temperature conditions is discussed. Then, two types of kilowatt-level lasers with significant applications--100 J, 10 Hz nanosecond lasers and 1 J, 1 kHz picosecond lasers--are presented, and the British DiPOLE system (105 J, 10 Hz, 10 ns) and the University of Colorado's laser system (1.1 J, 1 kHz, 4.5 ps), which are the holders of the highest indicators so far, are introduced.
## 3 Obstacle Vertex Extraction Algorithm Based on Equivalent Path
### Obstacle Vertex Extraction Algorithm (OVEA)  
The trajectory of the SGP varies depending on the distribution of obstacles. Directly searching for all obstacle vertices traversed by the SGP is extremely challenging, so it is necessary to break down the SGP. The eight-directional movement can be categorized into two types: movement along the coordinate axes (referred to as axial movement) and movement along the diagonal (referred to as oblique movement). Axial movement does not involve passing through obstacle vertices, whereas diagonal movement might. Therefore, when extracting obstacle vertices, the focus should be on the diagonal movements in the SGP.  
We also observed that in the SGP, there are three possible continuous movements: axial-oblique movement, oblique-axial movement, and oblique-oblique movement (axial-axial movement can be optimized at turns, which contradicts the definition of SGP). This implies that in SGPs, at least one of any two consecutive movements is an oblique movement. Based on this observation, we sequentially decompose a complete SGP into these three types of movement combinations and perform obstacle vertex extraction for each pair of consecutive movements.  
Figure 6: The 8-direction path can be divided into several equivalent path combinations.
###### Abstract  
A voltage-controlled oscillator (VCO) is an essential part of the clock circuitry in satellite communication systems. Low-dropout regulators (LDO) provide stable voltage supply to the VCO and inevitably bring in new radiation-sensitive nodes. In this paper, by conducting single-event transient (SET) sensitivity analysis of LDO in voltage-regulated VCO, we find the sensitive nodes of LDO in oscillation circuits located on the relevant transistors that determine the bias voltage of the tail transistor in the error amplifier (EA). To immunize SET, a symmetrical hardening method combining sensitive node splitting and resistive-decoupling is proposed for the sensitive nodes. This method achieves 80.8% analog single-event transient (ASET) mitigation. This study was conducted in 28-nm CMOS process.  
radiation-hardened-by-design (RHBD); single-event transient (SET); voltage regulator; low-dropout regulator (LDO); voltage-controlled oscillator (VCO)
## Materials and Methods
### Numerical Simulation Model Construction
#### 2.3.1 Numerical Model Parameter Validation
The physical and mechanical parameters of the block and joints applied in the numerical model are shown in Table 1. The fitting results of the uniaxial compression and tensile experiments show that the physical and mechanical parameters selected in Table 1 are reasonable. \begin{table}
\begin{tabular}{c c} \hline \hline
**Properties** & **Values** \\ \hline \hline Intact bulk modulus, \(K\) (GPa) & 6.5 \\ Intact shear modulus, \(G\) (GPa) & 2.8 \\ Normal stiffness of contacts, \(k_{\text{r}}\) (GPa/m) & 6100.0 \\ Shear stiffness of contacts, \(k_{\text{s}}\) (GPa/m) & 2440.0 \\ Contact cohesion, \(c^{\text{cont}}\) (MPa) & 29.4 \\ Contact friction angle, \(\Phi^{\text{cont}}\) (\(\circ\)) & 29.0 \\ Contact tensile strength, \(\sigma_{\text{r}}^{\text{cont}}\) (MPa) & 6.9 \\ Residual cohesion (MPa) & 2.0 \\ Residual friction (\(\diamond\)) & 15.0 \\ Residual tension (MPa) & 0.0 \\ Contact hydraulic aperture at zero normal stress, \(a_{0}\) (m) & 7.02 \(\times\) 10\({}^{-6}\) \\ Residual hydraulic aperture, \(a_{\text{res}}\) (m) & 1 \(\times\) 10\({}^{-7}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mechanical parameters obtained by sample fitting with the numerical model. Figure 7: Calibration of the numerical model to the Brazilian tests: (**a**) failure pattern of the laboratory sample; (**b**) failure pattern of the numerical model; and (**c**) stress–strain curve of the numerical model.
# Laser Cooling and Trapping of Rare-Earth-Doped Particles
###### Abstract  
This review focuses on optical refrigeration with the anti-Stokes fluorescence of rare-earth (RE)-doped low-phonon micro- and nanocrystals. Contrary to bulk samples, where the thermal energy is contained in internal vibrational modes (phonons), the thermal energy of nanoparticles is contained in both the translational motion and internal vibrational (phonons) modes of the sample. Much theoretical and experimental research is currently devoted to the laser cooling of nanoparticles. In the majority of the related work, only the translational energy of the particles has been suppressed. In this review, the latest achievements in hybrid optical refrigeration of RE-doped low-phonon micro- and nanoparticles are presented. Hybrid cooling permits the suppression of not only the translational energy of the RE-doped particles, but also their internal vibrational phonon thermal energy. Laser cooling of nanoparticles is not a simple task. Mie resonances can be used to enhance laser cooling with the anti-Stokes fluorescence of nanoparticles made of low-phonon RE-doped solids. Laser-cooled nanoparticles is a promising tool for fundamental quantum-mechanical studies, nonequilibrium thermodynamics, and precision measurements of forces.  
laser cooling of solids; rare-earth-doped materials; optical trapping; optical tweezers +
Footnote †: journal: Physics Letters A
## 3 Results
### Self-Similarity and Surface Equations  
The inner zone, characterized by Equation (2) and the outer zone, described by the Reissner-Nordstrom-Vaidya metric [16; 17], are separated by the hypersurface \(r=\sum\). Therefore, the coupling of the inner and outer solutions of the field equations must be considered. Furthermore, to know the evolution of the physical variables in the interior of the distribution (\(p,\rho,C,\varepsilon,\omega\)) in order to evaluate quantities over the surface, it is necessary to construct a system of ordinary differential equations relevant.  
Having done the above, a system of three ordinary differential equations is obtained, with three functions of time \(\mu\) associated with the radius of the distribution, the velocity at the edge of the distribution, and the function \(m\) evaluated at the surface.  
Some authors [37] characterized covariantly the self-similarity when the matter is distributed spherically, noting that the self-similar solutions depend on whether they are invariant or not in the presence of scale transformations. Seen mathematically, the interesting thing about self-similarity is that it helps to reduce the field equations to a group of ordinary differential equations, and, on the other hand, because it helps to generalize the symmetries, homothetic, and Killing symmetry, according to [38; 39; 40].  
To define self-similarity requires the existence of a homothetic Killing vector field. In a given coordinate system, self-similarity is evidenced by a simple scaling relation for the metric functions. Probably no problem in GR has been more exhaustively studied than that of spherically symmetric homothetic space-times [37].  
Now, an additional homothetic (self-similar) symmetry is imposed, which mathematically is expressed in Equation (28) [16; 17; 18].  
\[\mathcal{L}_{\xi}g_{\mu\
u}\ =\ 2g_{\mu\
u} \tag{28}\]  
where \(g_{\mu\
u}\) is the metric tensor, and the homothetical generator \(\xi\) is expressed as  
\[\xi^{\mu}\ =\ \Lambda(u,r)\delta^{\mu}\ +\ \lambda(u,r)\delta^{\mu} \tag{29}\]  
Putting Equations (28) and (29) together with (22) leads to  
\[\Lambda Y_{u}\ +\ rY_{r}\ =\ 0 \tag{30}\]  
and  
\[X_{u}\ +\ rX_{r}\ =\ 0 \tag{31}\]  
which can also be written as  
\[\xi(X(u,r))\ =\ 0 \tag{32}\]  
\[\xi(Y(u,r))\ =\ 0 \tag{33}\]  
By solving Equations (30) and (31), it is possible to know the form of the metric variables \(\beta\) and \(m\) for all \(Y(u,r)\).
# Improved Charge Injection and Transport of Light-Emitting Diodes Based on Two-Dimensional Materials
## 3 Two-Dimensional Materials in Quantum Dot Light Emitting Diodes (QLEDs)
\begin{table}
\begin{tabular}{c c c c c c} \hline
**2D Materials** & **Device Structure** & **Lmax (cd/m\({}^{2}\))** & **CF\({}_{max}\) (cd/A)** & **EQE\({}_{max}\) (\%)** & **References** \\ \hline GO & ITO/GO/rSC=Zs QDs/TPBi/LiF/Al & 165 & - & 0.125 & [58] \\ GO & ITO/GO/PVK:TCTA/sce=Zs core-shell QDs/ZnO/AI & 1309 & 0.6 & 0.77 & [59] \\ GO & ITO/GO/PEID:PSS/PVK:TCTA/sce=Zs core-shell QDs/ZnO/AI & 6741 & 1.34 & 1.61 & [59] \\ GO & TO/GO/PEID:PSS/TPB/Z:CMS (PS/TO)/AI & 4200 & - & - & [60] \\ GO & ITO/GO/PVK:CMS=Zs QDs/ZnO/AI & 7119 & 7.08 & 1.98 & [61] \\ rGO & ITO/GO/PVK:CMS=Zs QDs/ZnO/AI & 11,820 & 14.99 & 4.23 & [61] \\ \hline \end{tabular}
\end{table} 
Table 3: Summary of the device parameters of QLEDs incorporating 2D materials. results, the function of 2D materials in QLEDs is similar to those in OLEDs. However, there are only a few reports in this field and more related work can be expected.
## 3 System Model  
In this section, we introduce our system model by specifying its components including propagation, antenna models, traffic, and resource allocation models. We conclude this section by introducing the metrics of interest. The notation utilized in the paper is shown in Table 1.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Notation** & **Description** \\ \hline \(f_{c}\) & operational frequency \\ \(B\) & number of available RBs \\ \(\lambda_{A}\) & density of NR BSs \\ \(\lambda_{\text{B}}\) & density of blockers \\ \(\mu^{-1}\) & mean UE passage time \\ \hline \hline \end{tabular}
\end{table}
Table 1: Notation utilized in the paper.
## 2 Materials and Methods
### Materials  
Several data sets were investigated to be acquired for the purpose of this study. A Level 1T L7 image (path/row: 184/33), free of charge was obtained from the USGS Earth Explorer (EE) tool. The image was geometrically corrected and registered to a UTM 34N WGS84 ellipsoid with standard terrain correction applied. The L7 image was acquired on 23 May, hence one day after the two-day flood event [65]. It should be noted that Landsat-8 images were not available during the flood event. As well, S1 and S2 datasets were provided free via ESA's Sentinels Scientific Data Hub [66]. S1 data was an L1 GRD, high resolution (10 meters) Interferometric Wide (IW) image, of VV and HV polarization, using the Terrain Observation with Progressive Scans SAR (Table 1). The SAR image was obtained from S1 C-band during the flood, on 21 May (Time 07:05:10 pm). The available S2 products are in processing Level-1C, geometrically corrected and registered to the UTM 34N WGS84 ellipsoid with elevation correction applied. Four S2 images were acquired, from December 2015 till August 2016 (Table 1), so as to cover all the plant growth stages of the crops over a year and create the land cover classification map (Table 1).  
Topographic maps of the Hellenic Military Geographical Service (HMGS) were used to extract different types of info-layers: geomorphology, rivers, roads, railway tracks etc. A detailed DEM with 5 m spatial resolution and 0.5 m in geolocation, derived from topographical maps (scale 1:5000, contour interval 4m) of HMGS, was also used [67].  
Detailed spatial data of the utilized agricultural area (UAA) and the specific crop cultivated in each farm of the affected area during the study period were obtained by the Integrated Administration and Control System (OPEKEPE) [68] in the form of vector files with scale 1:10,000. Finally, compensation data of the Greek Agricultural Insurance Organization (ELGA) for the flood event period of the 20-22 May 2016 were processed and compared with the results of this study.  
The digital image processing and analysis of the satellite data were carried out using ENVI (v.5.3) and SNAP (v.5.0) software (Harris Geospatial Solutions, USA and European Space Agency, respectively), while the manipulation of the spatial information was made using ArcGIS (version 10.5.1, Environmental Systems Research Institute, Redlands, CA, USA).
# An Experimental Survey of Extended Resolution Effects for SAT Solvers on the Pigeonhole Principle
## 2 Preliminaries  
### SAT Problem  
The SAT problem consists of Boolean variables. A literal is either a positive form or a negative form of a Boolean variable. A positive (negative) literal is classified as true if the corresponding variable is deemed to be true (false). The SAT problem is given as Conjunctive Normal Form (CNF) in general, where a CNF consists of a conjunction (logical and) of clauses, and a clause consists of a disjunction (logical or) of literals. The SAT problem asks whether a variable assignment that satisfies (i.e., evaluates as true) the given CNF exists. [PERSON] proved the SAT problem is the first NP-complete problem [1]. An SAT instance is satisfiable if there is at least one valid variable assignment, otherwise it is unsatisfiable.
## 3 Verification through a Simple Beam Under Sinusoidal Loads
### Optimization Results
To test for overfitting and prediction accuracy, strains from the test dataset (periods 0.8 s) were input into the trained ANN, and the displacements predicted using the trained ANN were then compared with those predicted by the numerical analysis. When the displacements were predicted from four, three, and two strains, the MSEs were 0.0125, 0.0072, and 0.0524, respectively. Since there was no significant difference from the training MSE, overfitting did not occur, and the predictive accuracy of the trained ANN was very high. In Figures 7 and 8, the graphs are plotted for an intuitive comparison. Figure 7 shows the displacements over time at the beam center, depending on the number of strains. It can be seen that the fluctuation was very large when the strains at the arbitrary locations were used. However, when the strains at the optimized locations were used, the predicted displacements showed good agreements with the numerical results regardless of the number of strains. Figure 8 shows the beam displacement shape at t = 1 s, where the largest displacement occurs. In the case of using strains at arbitrary locations, the overall displacement shape was similar, but it can be seen that there was a large difference from the numerical results. However, when the strains at the optimized locations were used, the displacement shape was very similar to the numerical results. From the results, it could be seen that the ANN can predict the displacement shape of the beam under the dynamic load with very high accuracy when using the strain at the optimized locations by GA.