esa-sceva/satcom-chunk-collection huggingface dataset:
# Finger-Gesture Recognition for Visible Light Communication Systems Using Machine Learning
## 4 System Implementation
### VLC Transceiver  
The VLC system is implemented with real-time transmission and reception of symbols using an arbitrary waveform generator (AWG) and digital storage oscilloscope (DSO) as depicted in Figure 4. VLC data modulation/demodulation and activity recognition tasks are computed off-line using a personal computer with Matlab software.  
The Tx signal was generated with amplitude 1.80 V at 100 kHz in real-time using an arbitrary waveform generator Tektronix AWG 710B (max. 2.1 GHz bandwidth, 4.2 Gsa/s). An amplitude equalizer was inserted to counteract the low-pass frequency response of the LED. The amplitude equalizer provides about 7 dB loss at DC and the normalized gain rises to unity in the high-pass region at around 100 MHz. A Mini-Circuits ZHL-500 (0.1 MHz to 500 MHz) 17-dB gain-block is employed as a preamplifier to increase the small signal-level. The amplified data signal is added to a LED bias voltage of 4.2 v using a Mini-Circuits Bias-T ZFBT-4R2 GW-FT+ (0.1-6000 MHz bandwidth) and the output connected to a Luxeon Rebel LED via a standard SMA connector. The LED was selected as it is  
Figure 4: VLC for HAR system block diagram.  
Figure 3: LSTM algorithm unit structure.  
capable of supporting a data-rate in the order of 100 Mbit/s for communications. However, many other LEDs can also be used for the purpose of gesture recognition. The bias-T and amplifier had minimum operating frequency around 50 kHz. The bias voltage is adjusted to maximize the amplifier output power but backed off to avoid distortion. The amplifier, bias-T and LED were mounted onto a movable micro-stage platform to facilitate the alignment of the Tx.  
To increase the communication distance, a focusing-lens of diameter 40 mm was placed at both the Tx and Rx sides with a separation of 30 cm as shown in Figure 5. The focusing lens produces a narrow beam with optimum focus at the region where the hand is placed which is at the half-distance between Tx LED and RX PD. The required distance can be easily adjusted by increasing or decreasing the lens focal-range. In the current set-up if the hand is positioned away from the center-point then the signal-to-noise ratio (SNR) is reduced and therefore estimation accuracy will be degraded. A focusing lens is also an integral and necessary component in all VLC systems and so is not an additional cost. A consumer VLC system may likely employ directional Tx/Rx or an adaptive lens mechanism.  
A standard PD (Hamamatsu S10784 commonly used in DVD laser-discs) was employed at the receiver. The PD output was amplified by an OPA 2356 based low-noise amplifier (LNA) circuit that has a BW of about 200 MHz and was used here as a trans-impedance amplifier (TIA). The Rx waveform is detected by a PD and amplified by the LNA. LEDs generate incoherent light, which can be detected using simple direct or envelope detection circuitry. The Rx DSO was set at 2 Msa/s with a total 3.2 Mpoints stored after peak sampling.
# Aerodynamic Analysis of the Opening Hood Structures at Exits of High-Speed Railway Tunnels
## 1 Introduction
While scholars have extensively researched hood structures, most of these studies have focused on the aerodynamic impact of hoods installed at tunnel entrances, leaving a systematic exploration of the mitigation mechanism of exit hoods lacking. With the increase in tunnel construction length and train operating speed, relying solely on entrance hoods as a design standard presents certain limitations in terms of geographical conditions and economic costs. For instance, in some mountainous tunnel cases where the tunnel entrance or exit is connected to a bridge, it is not feasible to construct large-scale hoods. Consequently, trains must reduce their speed when passing through the tunnel, which significantly reduces the transport efficiency of high-speed railway lines. To address these concerns, this paper employs a combination of theoretical analysis and three-dimensional numerical simulation research methods. A comprehensive aerodynamic simulation model involving the train-tunnel-hood-air interaction is established. By comparing the mitigation effects of exit hoods with different opening ratios on the MPWs, the study validates that the opening ratio is a critical influential parameter for exit hoods. It separately calculates the impact of various opening forms of hoods on the spatial distribution pattern of MPWs and deduces the influence pattern of opening formson the effective solid angle. Additionally, the aerodynamic characteristics of MPWs after the installation of hoods at tunnel entrances and exits are analyzed. The research findings hold significant guiding implications for the design and optimization of hoods, offering novel perspectives for the design of tunnel entrance and exit hoods.
# Application of the Random Decrement Technique in Damage Detection under Moving Load
## 2 Basic Theories and Method
For auto and cross-RDSs, the following equations can be used [1]:  
\[Y_{mm}(\tau)=\frac{1}{N}\sum_{i=1}^{N}X_{m}(t_{i}+\tau)|\ X_{m}(t_{i})=a, \tag{7}\]  
\[Y_{mc}(\tau)=\frac{1}{N}\sum_{i=1}^{N}X_{c}(t_{i}+\tau)|\ X_{m}(t_{i})=a, \tag{8}\]  
in which \(Y_{mm}(\tau)\) is the auto-RDS calculated from the main signal (\(X_{m}(t)\)) and \(Y_{mc}(\tau)\) is the cross-RDS calculated from the signal \(X_{c}(t)\) using the triggering information of the main signal. Figure 3 shows the concept of auto and cross-RD signature. As shown in Figure 3, the segments of cross-RDS will be \begin{table}
\begin{tabular}{c c c} \hline
**Case No.** & **Description** & **Relation** \\ \hline
1 & Level crossing & \(T_{X}(t_{i})=\{X(t_{i})=a\}\) \\
2 & Positive points & \(T_{X}(t_{i})=\{a\leq X(t_{i})<b\}\) \\
3 & Zero crossing with a positive or negative slope & \(T_{X}(t_{i})=\{X(t_{i})=0,\quad\begin{array}{c}\hat{X}>0\\ \hat{X}<0\end{array}\}\) \\
4 & Local extremum & \(T_{X}(t_{i})=\{a\leq X(t_{i})<b,\hat{X}=0\}\) \\ \hline \end{tabular}
\end{table} 
Table 1: Triggering levels recommended by different researchers [1,22,24]. Figure 2: Basic concept of the special averaging in RD technique. chosen based on the instant times in which triggering level crosses the main signal. Thus, it is seen that the initial condition of cross-RDS is not equal to the triggering level \(a\). The triggering level in the main signal causes the auto-RDS to have an initial value equal to \(a\). However, this initial condition cannot occur for cross-RDS. Here, the initial value of cross-RDS is equal to the average of the \(N\) different starting instants of the signal \(X_{c}(t)\). Therefore, due to this special averaging procedure, the auto-RDS contains less noise than the cross-RDS [24]. As mentioned above, a mathematical solution for RD technique is only available for the zero-mean, stationary, Gaussian, and random white noise input excitations. However, most of the ambient and random excitations are non-stationary in nature, such as traffic on the bridges. A large body of research available on the literature employed RD technique to find the modal parameters and damages for non-stationary excitations [19; 25; 27; 28].
# A Maximum Likelihood Estimation Method for Underwater Radiated Noise Power
###### Abstract  
Underwater radiated noise power estimation is crucial for the quantitative assessment of noise levels emitted by ships and underwater vehicles. This paper therefore proposes a maximum likelihood estimation method for determining the power of underwater radiated noise. The method establishes the probability density function of the hydrophones array received data and derives the minimum variance unbiased estimation of the power through theoretical analysis under the maximum likelihood criterion. Numerical simulations and experimental data demonstrate that this method can significantly reduce the influence of ambient noise on estimation results and improve the estimation accuracy under low signal-to-noise ratio conditions, outperforming commonly used beamforming-based estimation methods. In addition, the estimation variance achieves the Cramer-Rao lower bound, which is consistent with theoretical derivation. When the source position is unknown, this method can simultaneously localize the sound source and estimate its power by searching for the maximum value within a specified region.  
underwater acoustics; radiated noise; power estimation; maximum likelihood; unbiased estimation Article
# Haze Removal Based on Refined Transmission Map for Aerial Image Matching
## 3 Results and Discussion
Hence, the results suggest that the proposed method yields better results on tested datasets and aerial images. Figure 8: Comparative test results of different dehazing methods using manually annotated dataset with [PERSON] (2016), [PERSON] et al. (2017), [PERSON] et al. (2017), and the proposed method. Figure 4.0 Matching based on C-SIFT: (**a**) original haze images (32 good matches), (**b**) [PERSON] and [PERSON] (2016) method (31 good matches), (**c**) [PERSON] et al. (2017) method (74 good matches), and (**d**) proposed method (85 good matches). Finally, the effect of enhancing the image contrast by eliminating the haze in an image is emphasized by the image-matching results shown in Figure 4.1 For the C-SIFT point-matching results, an experiment using a significant number of test images was conducted to support the point-matching related claims. When the C-SIFT operator was applied to the original hazy images, only 32 valid matches were produced. When the C-SIFT operator was applied to images enhanced using the method of [PERSON] [35], 31 valid matches were obtained. When the C-SIFT operator was applied to images enhanced using the method of [PERSON] et al. [40], 74 valid matches resulted. Finally, when the proposed method based on C-SIFT was used, 85 valid matches were generated. Additionally, we show the valid key point matching techniques compared to different methods in Figure 4.2 Of these methods, the proposed technique demonstrates more valid matches due to the reduction in block artifacts.
###### Abstract  
Mobile edge computing (MEC) supported by non-orthogonal multiple access (NOMA) has recently gained a lot of interest due to its improved ability to lessen power consumption and MEC offload delay. In recent decades, the need for wireless communications has increased tremendously. Fifth-generation (5G) communications will soon be widely used and offer much more functionality than a fourth generation (4G). Between 2027 and 2030, an innovative wireless communication paradigm is known as the sixth generation (6G) system is projected to be introduced with the full help of artificial intelligence (AI). Advanced system capacity, higher data rate, lower latency, advanced security, and improved quality of service (QoS) than 5G systems are a few of the main challenges to resolve with 5G. The growing need for data rates in the sixth generation (6G) communication networks are being met by extraordinary technologies such as NOMA, Soft Computing (SC), and MEC. Owing to the massive attention to the NOMA-enabled MEC, there has been a significant spike in the number of papers published in this area, while more comprehensive studies and classifications are still needed. Using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, the investigation reports a systematic literature review (SLR) of NOMA-enabled MEC. This survey also evaluates numerous pieces of literature prudently chosen over a multi-step procedure and meets the selection criteria described in the paper summarizing our review.  
6G communication network; non-orthogonal multiple access; mobile edge computing; artificial intelligence 2023  
[EMAIL_ADDRESS]  
[PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Non-Orthogonal Multiple Access Enabled Mobile Edge Computing in 6G Communications: A Systematic Literature Review.
## 9 Conclusions  
Two common-mode voltage (CMV) reduction PWM schemes based on the SVM technique for a nine-phase induction drive system have been proposed in this paper, and the following conclusions can be derived.  
1. By replacing the zero vectors in the conventional SVM technique with two opposite active vectors (selected to reduce the CMV and to give the minimum number of commutations), the peak CMV was reduced by 22.2%, and the peak CMV became \(\pm 7V_{dc}/18\) instead of \(\pm V_{dc}/2\) in the conventional SVM scheme.
2. In the second method, called the SV-10L scheme, the peak CMV was reduced to \(\pm V_{dc}/18\) In this scheme, ten large active vectors selected from the \(\alpha\beta\) subspace were used during a switching period. The dwelling times of these vectors in the \(xy\) plane were determined to nullify the harmonics and were used in the implementation.
3. Notably, the second scheme gave minimum CMV magnitude with constant switching frequency and minimum error vectors. It reduced the peak CMV by 88.8% compared with the conventional SVM scheme.  
Moreover, the implementation of the proposed schemes using simple carrier-based PWM approaches was presented. In this approach, two opposite symmetrical triangular carrier waves were utilized. The CMV analysis for the conventional and proposed schemes was presented.  
Simulation and experimental results of conventional and proposed PWM schemes were provided to verify their effectiveness and their effect on motor performance. The experimental results showed good agreement with the simulation results by comparing the conventional and the proposed schemes. The proposed schemes have a slightly distorted motor current in the experimental study; therefore, lower efficiency is expected compared to the conventional SVM.  
Conceptualization, and software, S.M.D.; methodology, A.S.A.-K.; validation, S.A. and A.M.M.; formal analysis, I.A.G.; investigation, A.A.A.; resources, M.E.F.; experimental work, M.A.E.; writing--original draft preparation, S.M.D.; writing--review and editing, A.A.A. and A.S.A.-K.; visualization, A.M.M.; supervision, M.E.F.; project administration, S.A. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
Open Access funding provided by the Qatar National Library.  
The authors declare no conflict of interest.
## 2 Materials and Methods  
### Animal Care and Extended Liver Resection  
The study included male Wistar rats (\(n=190\)). Among them, 160 six- to eight-month-old animals weighed 400-450 g, and 30 five- to six-month-old animals weighed 350-400 g. The rats stayed in our vivarium at 22-24 \({}^{\circ}\)C with 12 h light-dark cycle and a mixed diet (Laboratorkorm, Russia) _ad libitum_ and free access to water (tap water was sterilized and distillated prior to the watering). We kept cages with animals in horizontal laminar flow cabinets for housing cages with laboratory rodents (CLJ-18; 3W, Moscow, Russia). The regulatory standards for the equipment accorded with GLP rules. Temperature and relative humidity were monitored twice a day using a thermometer and a psychrometer. The animal cage had a protruding upper bar, providing shading and allowing the animal to choose a dark area of the cage to stay in during the day with bright lighting.  
Three rodents were kept per a cage, with respect to randomization, and sterile wood shavings delivered in vacuum bags served for the bedding (Laboratorkorm, Moscow, Russia). The experiments with animals took place from 9 am to 7 pm at 22-24 \({}^{\circ}\)C to avoid differences in mitotic activity of hepatocytes.  
All the manipulations with animals fulfilled requirements of local Ethics Committee, National Guidelines on Animal Care, and European Convention for the Protection of Vertebrate Animals used for research and other scientific purposes. The animal study protocol was approved by the Ethics Committee of Federal State Budgetary Institution \"Shumakov National Medical Research Center of Transplantology and Artificial Organs\" of the Ministry of Health of the Russian Federation (protocol No. 050221-1/3e 05/02/21) for studies involving animals.  
Younger rats (\(n=30\)) served to obtain HSCs. Older rats (\(n=160\)) experienced extended (75%) liver resection (ELR) according to common approaches [30; 31]. Due to inability to accomplish all the experiments and surgeries on the same days, we performed eight consecutive rounds with 5 animals per group, considering the pilot experiment also, and then rejoined the numerical data for statistical processing.  
The surgery was accomplished as follows. After an aseptic access to abdominal cavity by midline incision, we ligated and removed middle (35-40%), left lateral (25-30%), and right superior lobes (15-20%), then the peritoneum and skin were sutured. Surgical manipulations took place at 10-12 am with isoflurane anesthesia (Laboratories Karizoo, Barcelona, Spain). At the early post-surgery stage, the animals had signs of acute liver damage.  
Animals were sacrificed by increasing CO\({}_{2}\) concentration on Days 1, 3, 5, 7, 10, 14, and 20. Immediately after this, we collected their blood by notching the tail tip and removed the liver to weigh and then to put into 10% neutral buffered formalin Histosafe (cat. No. B06-001/L; ErgoProduction, Saint Petersburg, Russia).
# Quantitative Assessment of Upper- Limb Volume: Implications for Lymphedema Rehabilitation?
## 4 Methods for Volumetric Assessment
### Perometry  
Perometry is a modern volumetric assessment technique that utilizes infrared light scanning to measure limb volume in individuals with lymphedema. This non-invasive method offers a more advanced and comprehensive approach compared to traditional circumferential measurements, providing detailed information about limb size and shape [39]. The principle of geometry involves projecting infrared light onto the limb and capturing the reflected light using sensors. The system can generate a three-dimensional limb representation by analyzing the light patterns, allowing for accurate volume measurements [44].  
One of the primary advantages of geometry is its ability to provide precise and objective volumetric measurements. Unlike circumferential measurements, geometry accounts for variations in limb shape and contour, providing a more accurate representation of volume changes [44]. The technique also allows for the assessment of both the affected and unaffected limbs, facilitating side-to-side comparisons and aiding in the identification of asymmetry.  
Perometry offers additional benefits in terms of convenience and patient comfort. The scanning process is quick and can be performed without direct contact with the limb, reducing discomfort for individuals with sensitive or fragile skin. Furthermore, geometry can be easily repeated at regular intervals, enabling regular monitoring of limb volume changes and treatment progress [45].  
Several studies have demonstrated the effectiveness of perometry in assessing limb volume in lymphedema [8, 39, 46]. The technique has shown good agreement with other established volumetric assessment methods, such as water displacement, and has been validated in clinical practice. Its accuracy, ease of use, and reliability make perometry a valuable tool for clinicians in the diagnosis, staging, and monitoring of upper-limb lymphedema [8, 39, 46].  
While perometry has numerous advantages, it is important to consider certain limitations. The availability and cost of perometry systems may be a barrier to its widespread use, particularly in resource-limited settings. Additionally, the technique requires propertraining and standardization to ensure consistent and accurate measurements [47]. Further research and validation studies are needed to establish standardized protocols and guidelines for its implementation in rehabilitation clinical practice.
# Hybrid Wavelet-CNN Fault Diagnosis Method for Ships' Power Systems
## 5 Results
### Discussion  
The custom fault-detection challenge-indicative levels from Tables 5-9 show that the harmonic frequencies of the faults were captured in most cases, providing valuable initial information, but there were cases where it was extremely difficult to diagnose nonintense faults, especially in noisy simulated data. Furthermore, the appropriate selection of the mother wavelet and the level of decomposition are key factors for this particular application. After feature extraction using DWT, the power of 1D CNN models was utilized to complete the novel hybrid discrete wavelet-CNN model.  
A main distinction of our research compared to related works is that the currents were obtained from simulations that included various load conditions, types, intensities of faults, and scales of white noise. The combination of 1D CNN and DWT is the other distinction of our research, and it was employed to automatically diagnose even more indistinguishable and complex faults. The proposed method could also be considered the first step towards the development of a complete diagnostic system that is able to detect and predict all types of IM faults from transfer learning on the basis of simulation data, and able to be implemented to reduce the training costs of experimental analysis.
# Design and Mechanical Properties of Flat Anchorage Limit Plate
## 4 Mechanical Properties of Flat Anchorage Limit Plate
### Tensile Stress Distribution of Single Hole  
According to the numbering in Figure 5, single-hole tension was separately applied to holes 1, 2, and 3, with a tension tonnage of 20 t, i.e., a tension force of 196 kN. Figure 6 shows the stress distribution of the flat anchorage under the two conditions. The figure shows that, after using the limit plate, the stress concentration on the flat anchorage was alleviated, and the extreme stress value decreased from 245.76 kPa to 219.43 kPa, representing a decrease of 10.7%. This also occurred in the tension of holes 2 and 3 alone. The extreme stress values are shown in Table 2, showing more notable decreases of 45.9% and 48.3%, respectively. The stress relaxation of hole 3 in the middle was the most remarkable. We found that the tension force is shared by the newly added limit plate, which is a replaceable member, whereas the flat anchorage is a permanent member; hence, the adverse effects of the tension force can be passed on to the replaceable limit plate, thus improving the reliability of the flat anchorage. We calculated the standard deviation of the extreme stress value of a conventional flat anchorage as 19.02 kPa and that of new flat anchorage system as 60.86 kPa. The limit plate had differing effects on the tension results of the different hole positions.
# RSSI and Device Pose Fusion for Fingerprinting-Based Indoor Smartphone Localization Systems
### Scope and Outline  
The novel framework proposed in this paper is a conceptual data-level framework that can be implemented using any pattern recognition algorithm. The implementation and  
Figure 2: Power-based fingerprinting localization approach.  
results of the framework using cascaded neural networks is described in detail, and results using K-Nearest-Neighbor and Naive-Bayes are given to demonstrate that the framework has utility when implemented using other algorithms as well. Hence, this paper does not propose a new _algorithm_; we explore the novel combination of device pose data with RSSI data to produce an increase in localization accuracy over RSSI-only data, as this has not been explored in the literature. The selection or optimization of a pattern recognition algorithm to implement the framework was not within the scope of this study.  
The remainder of this paper is structured as follows: Section 2 reviews related literature and details the rationale behind the proposed framework; Section 3 describes the proposed framework and its implementation using cascaded neural networks, and specifies the experimental setup. Section 4 presents detailed results and analysis of accuracy improvements; Section 5 discusses the advantages and disadvantages of the proposed framework and provides the conclusion to the paper.