esa-sceva/satcom-chunk-collection huggingface dataset:
## 5 Discussion and Conclusions  
This research proposed EUMTS, a seamless, lossless real-time transmission solution for the monitoring of preterm birth. A previously published algorithm was modified and applied to uterine EMG signals and optimized for uterine EMG. The developed algorithm had a higher \(CR\) and lower \(PRD\) than other widely used algorithms and those proposed by others.  
A higher compression digital signal ratio is important, especially for screening for pre-term birth. Without compression, the massive size of the EMG data overloads the network, resulting in network outages and a high battery-power consumption. The results in this proposed research showed that the proposed algorithm contributes to a reduction in battery consumption by reducing the wake-up time by 1470.6 ms. A unique compression technique has additional external affects such as network security and preventing privacy issues [31], blocking any trespassers trying to interrupt the medical system network.  
Using the proposed algorithm, maternal EMG signals can be transmitted seamlessly through telemedicine networks. Signals can be compressed with a high efficiency, with more data being transmitted at a higher speed under limited bandwidth situations [32]. Also, the data recovery time is reduced, even if errors occur.  
Moreover, digital EMG signals are important indicators of maternal health, and any data loss leads to the possibility of clinical decision errors. The solution proposed in this study is a lossless transmission solution, and is appropriate for EMG signals because EMG signals are precious indicators and information of patients.  
The proposed study is also a real-time supporting transmission solution, which is especially fit for telemedicine systems where immediate intervention from medical experts is needed in cases of emergency [33].  
In conclusion, EUMTS will contribute to providing a safe, seamless environment for the prediction of pre-term delivery so that immediate interventions by medical professionals can be applied. Pre-term babies may receive appropriate care immediately after birth, before being exposed to infection or contamination, thereby preventing the development of disabilities. Future research should include imbedding the solution algorithm inside a practical EMG acquiring device and performing real tests to measure the power consumption and real-time performance. Moreover, a compatible smartphone app that provides support and advice to the pregnant women should be developed.  
This research was funded by Korea University, Seoul, South Korea. [Grant number K1605491].  
**Author Contributions:** [PERSON] is the first author and the head developer of this research. [PERSON] analyzed the data, performed the evaluation, and wrote the article. [PERSON] is the corresponding author and managed the overall research.  
**Conflicts of Interest:** The authors declare no conflict of interest.
# A Polarization-Dependent Frequency-Selective Metamaterial Absorber with Multiple Absorption Peaks
## 4 MA Absorption Dependence on the Wave Incident Angle and Polarization  
The absorption characteristics of the proposed structure for oblique incident wave with TE polarization were simulated, and the obtained results are shown in Figure 6a. During the calculation, \(E\)-field was in the \(x\)-direction, and \(H\)-field and wave propagation directions varied simultaneously for angle \(\theta\).As shown in Figure 6a, when the oblique incident angle increases from 0 to 60\({}^{\circ}\), the absorption peaks at the three resonance frequencies are about 90% or greater, which is caused by a resonator structure, wherein for TE polarization a strong electric resonance can be excited with a relatively small field strength.  
For the TM-polarized wave, whose \(H\)-field is in the \(x\)-direction, the absorption characteristics for the oblique incident wave were also simulated, and the obtained results are shown in Figure 6b. However, as can be seen in Figure 6b, when the incident angle increases, the absorption characteristic for TM-polarized oblique incidence deteriorates rapidly at all resonance modes.  
Nonetheless, we were focused on absorption characteristics for different polarization angles for the normal incident wave. For TE and TM polarization, \(E\)-field changes for angle \(\varphi\) with respect to the \(x\)-and \(y\)-direction, respectively. The simulated responses for TE and TM waves for different polarization angles are presented in Figure 7a,b, respectively. As shown in Figure 7a, for resonant modes\(f_{1}\) and \(f_{3}\), the absorption is high when \(\varphi\) is in the range 0-45\({}^{\circ}\). However, the resonance of mode \(f_{2}\) decreases gradually when \(\varphi\) changes from 0 to 45\({}^{\circ}\). According to results presented in Figure 7a, it can be concluded that the resonance of mode\(f_{2}\) vanishes at \(\varphi=45^{\circ}\) because the surface current on the resonator surface in mode\(f_{2}\) (Figure 3c) mainly flows perpendicularly to the direction of the electric field vector. Therefore, the electric response cannot be excited.  
Figure 5: Distribution of ohmic losses on resonator surface at **(a)** 92.4 GHz; **(b)** 102.0 GHz and **(c)** 130.1 GHz.  
Figure 6: Simulated responses of the structure for different incident angles \(\theta\) for **(a)** the TE-polarized wave and **(b)** the TM-polarized wave.  
Similarly, when TM polarization angle is changed, the absorption peaks for mode \(f_{2}\) are above 80%, while the absorptivities of mode \(f_{1}\) and \(f_{3}\) decrease gradually when \(\varphi\) changes from 0 to 45\({}^{\circ}\). Therefore, the proposed structure provides both single-band and multi-band absorption for different polarization angles.
###### Abstract  
We present our recent results, related to nanoscale imaging in the extreme ultraviolet (EUV) and soft X-ray (SXR) spectral ranges and demonstrate three novel imaging systems recently developed for the purpose of obtaining high spatial resolution images of nanoscale objects with the EUV and SXR radiations. All the systems are based on laser-plasma EUV and SXR sources, employing a double stream gas puff target. The EUV and SXR full field microscopes--operating at 13.8 nm and 2.88 nm wavelengths, respectively--are currently capable of imaging nanostructures with a sub-50 nm spatial resolution with relatively short (seconds) exposure times. The third system is a SXR contact microscope, operating in the \"water-window\" spectral range (2.3-4.4 nm wavelength), to produce an imprint of the internal structure of the investigated object in a thin surface layer of SXR light sensitive poly(methyl methacrylate) photoresist. The development of such compact imaging systems is essential to the new research related to biological science, material science, and nanotechnology applications in the near future. Applications of all the microscopes for studies of biological samples including carcinoma cells, diatoms, and neurons are presented. Details about the sources, the microscopes, as well as the imaging results for various objects will be shown and discussed.  
gas puff target; Fresnel zone plates; EUV/SXR microscopy; contact microscopy; imaging; nanometer resolution +
Footnote †: journal: Applied Physics Letters
# Scalable Photonic Digital-to-Analog Converters
## 2 The Proposed Parallel PDAC Architecture
Assuming 0.1 dB insertion loss for an MMI, 0.5 dB loss for the MRM, and considering the operating point being located on the slope of the resonance dip (7 dB below the peak transmission off the resonance, asas discussed in the next section), roughly seven bits can be accommodated for an error-free DAC operation, with an average optical power of \(-20\) dBm in the LSB if the system noise is below \(-23\) dBm. In its standard configuration, the PDAC output is an analog optical signal, suitable for pulse amplitude modulation (PAM). The individual microrings operate as intensity modulators with minimal phase modulation for constructive interference at the MMI summations. We use MRMs operating in the under-coupled regime to suffice these criteria, as illustrated by the phase response of the MRM (shown in Figure 3a), which is measured using an optical vector analyzer. The PDAC output is a PAM-2N signal where N is the number of parallel MRMs of the PDAC. In addition to PAM, the proposed PDAC architecture can also be used to generate coherent quadrature amplitude modulation (QAM). Two parallel PDACs are needed, one generating the I-component, and the other the Q-component of the QAM signal. In such a scheme, the PDAC architecture remains unchanged, but the microrings must operate as \(\pi\)-phase shifters with a constant steady-state amplitude. This can be achieved with MRM in an over-coupled regime, as seen in Figure 3b. By operating the MRMs this way, the PDAC output is no longer of a PAM nature, but a coherent I- or Q-component of the 2N-QAM signal. Figure 2: A schematic diagram of the proposed PDAC architecture for N-bit resolution. The input CW light is divided/distributed into branches using 3-dB MMI-based splitters. The signal in each branch is digitally switched by a microring-based modulator. A thermo-optic phase shifter (PS) is adopted in every branch to enable coherent coupling of the modulated signals through the output MMI-based combiners. One module, consisting of two MMIs, an MRM, and a PS, is marked by a dashed box.
# A Novel Method of Emotion Recognition from Multi-Band EEG Topology Maps Based on ERENet
## 2 Materials and Methods
### An Emotion Recognition Method from Multi-Band EEG Topology Maps Using ERENet
#### 2.3.2 The Model of Proposed ERENet
Let \(F=\left\{F_{1},F_{2},\ldots,F_{\mu\times\lambda}\right\}=H\) denote the fused features' output by the previous module, and \(F_{i}=\left\{F_{1},F_{2},\ldots,F_{\mu\times\lambda}\right\}(i=1,2,\ldots,\mu \times\lambda)\) denote the \(i\)-th feature map, where \(s_{j}(j=1,2,\ldots,h\times w)\) represents the feature value at the \(j\)-th position of the feature map. Therefore, when aggregating feature values at the \(j\)-th position of all feature maps, a learnable weight \(\eta_{i}^{j}(i=1,2,\ldots,\mu\times\lambda)\) is assigned to each position, and the extracted features can be expressed as shown in Equation (8):  
\[c_{j}=\eta_{1}^{j}\times s_{j}^{F_{1}}+\eta_{2}^{j}\times s_{j}^{F_{2}}+\ldots +\eta_{\mu\times\lambda}^{j}\times s_{j}^{F_{\mu\times\lambda}}=\sum_{i=1}^{\mu \times\lambda}(\eta_{i}^{j}\times s_{j}^{F_{i}}),\;\;\;j=1,2,\ldots,h\times w, \tag{8}\]  
\(F_{\text{CWP}}=\left\{c_{1},c_{2},\ldots,c_{h\times w}\right\}\) represents the feature extracted from feature maps \(F\). Therefore, channel-weighted pooling not only reduces the feature dimension, but also filters different fusion features to further extract more representative features. The fully connected layer is not completely discarded, and one is added between the channel-weighted pooling and the output layer to enhance the feature representation. The final feature vector \(F_{\text{FC}}\) is shown in Equation (9):  
\[F_{\text{FC}}=FC(F_{\text{CWP}}),\;\;\;F_{\text{FC}}\in\mathbb{R}^{m}, \tag{9}\]where \(m\) represents the number of neurons in the fully connected layer. In the output layer, the feature vectors \(F_{\text{FC}}\) are aggregated, and the aggregated result is activated by Sigmoid to obtain the final prediction result, as shown in Equation (10):  
\[P=sigmoid(FC(F_{\text{CWP}})),\ \ \ P\in(0,1), \tag{10}\]  
In the traditional classification layer as shown in a, the total number of parameters is \(h\times w\times C\times m+2m+1\) from the feature vector \(h\times w\times C\) flattened into a 1D vector, then through the fully connected layer to the output layer. The number of parameters of the weighted classification module is \(h\times w\times(C+m)+m+1\) as shown in Figure 6b. \(C\) represents the number of feature maps' output by the previous module and \(C=\mu\times\lambda\). Although the weighted classification module only replaces a fully connected layer with a channel-weighted pooling layer, this module only has 10,784 trainable parameters, which is a reduction of 41,077 trainable parameters compared with the previous classification layer that was only composed of full-connection layers. Moreover, the model with channel-weighted pooling layer achieves better results than other models with similar parameter quantities.
# Optical Chirality Determined from Mueller Matrices
## 4 Results
### Optical Activity in Liquid Crystals
#### 4.4.3 Method III  
It was found that the chirality parameter \(\kappa\) could not be fitted over the full experimental spectral range when using Method III. The linear regression failed in the Bragg band. However, for wavelengths larger than 450 nm, a combination of Gaussian oscillators and Cauchy terms were used to model \(\kappa\), \(\Delta n_{xy^{\prime}y^{\prime}}\), and \(\Delta k_{xy^{\prime}y^{\prime}}\) in Equation (12). For wavelengths shorter than 375 nm, the experimental data could be modeled but the model fits to the data for the ChGLC sample should only be considered as mathematical fits, and a physical interpretation of Gaussian resonance energies, etc. is of limited value. The model fits are shown in Figure 10.  
The obtained model data represent the bianisotropic optical properties of the sample and allow \(C_{\text{B}}\) and \(C_{\text{D}}\) to be calculated from Equation (14) as shown in Figure 12. For wavelengths larger than the Bragg band, both \(C_{\text{B}}\) and \(C_{\text{D}}\) are in very good agreement with the corresponding data obtained with Method II. This also holds for \(C_{\text{D}}\) for wavelengths shorter than the Bragg band, whereas the \(C_{\text{B}}\) data from Method III are much more negative than those obtained from Method II.  
The curvature of \(C_{\text{B}}\) for short wavelengths may be an artifact due to that the transmission drops below 350 nm, which may induce systematic errors. Another more interesting possibility is that dispersion in ChGLC optical properties may generate additional Bragg resonances [30; 31]. The large offset in \(C_{\text{B}}\) leads to values of the order \(-65\) rad as seen in Figure 12. This corresponds to a rotation of polarization \(\alpha=C_{\text{B}}/2\approx 1800^{\circ}\) or, if normalized to the 10 \(\upmu\)m thickness, to 180,000\({}^{\circ}\)/mm. This appears surprisingly large, but liquid crystals may have very high rotatory power, even hundreds of revolutions per mm [32]. Even larger rotations have been observed in 20-nm thin films of squaraine, where a maximum in \(C_{\text{B}}=0.2\) rad corresponds to a rotation approaching \(3\times 10^{5}\)[6].
## 3 Results  
### Kaempfer Inhibits HeLa Cell Proliferation  
The cytotoxic effect of Kaempfer was assessed by MTT assay by exposing HeLa cells with different concentrations of Kaempfer (1-100 uM) for 24 and 48 h. It is evident from Figure 1A that kaempfer reduces cell viability in both dose- and time-dependent manner, which ranged from 96-73% at 24 h and 90-37% at 48 h. The IC\({}_{50}\) value was estimated to be 50 uM at 48 h. The experiments were repeated at least thrice, and the average is shown in the given result (Figure 1A). On the contrary, kaempfer treatment (1-200 uM) exhibited an insignificant difference in the cell viability of cardiomyocyte (AC-16; normal cell line). Moreover, kaempfer (30, 40 and 50 uM) altered the appearance of treated HeLa cells compared to the control, which was assessed by an inverted microscope. The dead cells were rounded off, detached and floating, and their proportion increased with increasing dose of kaempfer (Figure 1B).  
Figure 1: Kaempfer exhibits cytotoxic effect on HeLa cells (**A**) Graph presenting concentration and time dependent reduction in cell viability of HeLa cells after treatment with kaempfer (1-100 uM)for 24 h and 48 h, respectively, In all the assays, the effect of drug on treated cells was compared with DMSO controls. The half inhibitory concentration (IC\({}_{50}\)) of kaempfer was found to be 50 uM at 48 h. The data are expressed as the mean \(\pm\) standard deviation of three independent experiments. Statistically significant differences are marked by asterisks: Two way-ANOVA * represents \(p<0.05\). *** \(p<0.001\). (**B**) Microscopic analysis of treated cells: Kaempfer treated HeLa cells at various concentrations (30, 40 and 50 uM) at 24 h and 48 h illustrated characteristic rounding off of the dead cells, signifying apoptosis at 10 \(\times\) Magnification. (**C**) Nuclear morphology after PI staining of kaempfer-treated HeLa cells (30, 40 and 50 uM) shows a concentration-dependent increase in apoptotic index. Orange = prominent intact nuclei, Blue = membrane blebbing, Gray = nuclear fragmentation, green = Apoptotic bodies. (**D**) Kaempfer treated HeLa cells with 30, 40, 50 uM for 48 h produced a DNA laddering pattern on agarose gel in concordance with nuclear fragmentation, a characteristic feature of apoptosis.
# Additive Manufacturing of Variable Density Lenses for Radio Frequency Communications in X-Band
###### Abstract  
This paper presents three realizations of a complete set with a horn antenna and a focusing Gradient Index (GRIN) lens in X-band. The set was specifically designed for advancing additive manufacturing (AM) of polymers with different materials and techniques. The set has three constituent parts: a horn antenna, a support, and a lens. The horn antenna is the active element and must be electrically conductive; it was manufactured with Rigid10K acrylic resin and subsequently metallized using an electrol process. The support needed to be light, robust, and electrically transparent, so that Polyamide 11 (PA11) was used. The lens realization was intended for a dielectric material whose permittivity varies with its density. Therefore, the dielectric permittivity and loss tangent of different polymeric materials used in AM at 2.45, 6.25, and 24.5 GHz were measured. In addition, stochastic and gyroid mesh structures have been studied. These structures allow for printing a volume that presents porosity, enabling control over material density. Measuring the dielectric characteristics of each material with each density enables the establishment of graphs that relate them. The sets were then manufactured, and their frequency response and radiation diagram were measured, showing excellent results when compared with the literature.  
additive manufacturing; lattice structures; complex permittivity; lens design Article
# Quantum Perspective on Digital Money: Towards a Quantum-Powered Financial System
## 5 Security of Quantum Money: Attack Vectors and Countermeasures
### Potential Attack Vectors  
* Physical tampering and hardware attacks: As with any technology relying on physical devices, quantum wallets and quantum memories may be vulnerable to physical tampering. This includes invasive attacks aimed at extracting stored states or damaging memory coherence.  
* Side-channel attacks: Imperfections in device design may allow adversaries to infer information about quantum states through measurable side effects, such as timing, power consumption, or emitted radiation.
* Spoofing and impersonation: If a malicious actor is able to intercept classical metadata (e.g., serial numbers or digital certificates), they might attempt to present a fake quantum state that mimics valid money, especially if the verification procedure is not sufficiently robust.
* Attacks on quantum communication channels: During quantum teleportation or entanglement distribution, an adversary may attempt a man-in-the-middle attack, injecting noise, faking entangled pairs, or disrupting transmission fidelity.
* Forgery via imperfect verification: If the verification algorithm \(M\) for quantum money accepts invalid states with non-negligible probability, adversaries could attempt to produce counterfeit quantum states that pass as legitimate currency.
# A Semantic Segmentation Dataset and Real-Time Localization Model for Anti-UAV Applications
## 2 Related Work
### Anti-UAV Dataset  
We focus exclusively on datasets that use UAVs as the primary class for detection. Multi-class datasets containing UAVs alongside other objects are omitted to maintain relevance to the specific task. Several datasets dedicated solely to UAV detection have been developed. MAV-VID [25] is a public dataset consisting of 64 videos of flying UAVs, totaling 40,323 images extracted from video frames. Among the 64 videos, 53 are designated for training and 11 for validation. In this dataset, UAV movements are predominantly horizontal, and UAVs are mainly centered in the images. MAV-VID contains only RGB images and is publicly accessible on the Kaggle platform.  
The Anti-UAV dataset [22] initiated the first Anti-UAV Challenge & Workshop. It comprises 318 annotated videos for object detection and tracking tasks, including both RGB and IR images with corresponding labels. UAV positions in this dataset are mostly concentrated near the center of the images. The dataset features varying UAV object sizes, promoting more reliable detection performance.  
[PERSON] et al. [21] proposed a dataset that integrates images from three UAV datasets: MAV-VID [25], Drone-vs-Bird [26], and Anti-UAV [22]. This combined dataset serves as a benchmark for UAV detection and tracking, evaluated using various state-of-the-art models such as Faster R-CNN [20], YOLOv3 [27], SSD [19], DETR [28], SORT [29], Deep-SORT [30], and Tracktor [31].  
The DUT-Anti-UAV dataset [23] is another large-scale resource designed for UAV detection and tracking. It improves upon the Anti-UAV and MAV-VID datasets by providing a more diverse UAV distribution with scattered positions throughout the images. The dataset exhibits a more uniform horizontal and vertical distribution of UAVs. It also includes 35 different UAV types, increasing object variety. Most images feature small-sized UAVs, which pose challenges for model performance due to the increased difficulty of detection and higher likelihood of failure.  
To date, no publicly available dataset focuses specifically on the semantic segmentation of UAVs. In this paper, we propose and release a UAV semantic segmentation dataset. This enables more precise UAV localization in images, particularly for small-sized UAVs, by leveraging pixel-level classification rather than bounding boxes.