esa-sceva/satcom-chunk-collection huggingface dataset:
## 2 The Proposed Converter
### Design of the Proposed Hybrid Converter for AC-DC Adapter Applications  
As seen in Figure 3, the proposed hybrid converter includes one controlled switch, two diodes, three decoupled inductors, two coupling capacitors, and two low-pass filters (shunt filter capacitor with load resistance). The proposed hybrid converter is assumed to operate in continuous current mode (CCM) for the sake of simplicity. The discussion that follows demonstrates proper converter parameter selection for CCM operation mode. The components of the proposed hybrid converter are selected based on the procedure used in [31; 32].  
The design parameters are chosen to supply an electric vehicle; the DC output voltage (motor voltage) is 200 V (output voltage 3, see Figure 3). However, the load's rated output is 25 kW. Since the circuit will use an AC RMS line voltage as its input, the average rectified voltage is determined to be 200 V DC. The switching frequency is set at 20 kHz. All inductors' ripple current percentages are set to 20%. In contrast, the output voltage ripple should not be lower than 10% of the target output voltage. The selected design parameters and their associated values are shown in Table 2.  
Figure 6: Voltage gain vs. duty cycle.  
Moreover, the proposed converter belongs to the category of DC-DC converters. As seen in Figure 3, it contains three inductors. The main milestone is the design (size) of these inductors. The inductor size is inversely proportional to the selected switching frequency. But increasing the switching frequency will deteriorate the converter efficiency. Therefore, selecting the switching frequency is a crucial issue.
## 3 Results and Discussion
Similarly, under the impact of strong turbulences, an acceptable BER (\(\leq\)10\({}^{-3}\)) is computed for User 1, User 2, User 3 and User 4 at the FSO transmission ranges of 1720, 1600, 1520 and 1150 m, respectively. For User 5, User 6, User 7 and User 8 under the impact of weak turbulences, an acceptable BER (\(\leq\)10\({}^{-3}\)) is achieved at FSO transmission ranges of 2100, 1500, 1700 and 1300 m respectively, as shown in Figure 4b. However, the maximum FSO ranges under strong turbulence for User 5, User 6, User 7 and User 8 are 1150, 1000, 700 and 800 m, respectively. Figure 6a,b presents the BER performance of the proposed OCDMA-based MDM-FSO-MMF system over a fixed 300 m fiber along with a variable FSO range employing a log-normal turbulence model. The figure shows that the value of an acceptable BER for User 1, User 2, User 3 and User 4 under the impact of weak turbulences is achieved at the FSO transmission distances of 2100, 1800, 1900 and 1500 m, respectively. On the other hand, under the impact of strong turbulences, the required BER is computed for the User 5, User 6, User 7 and User 8 at the FSO ranges of 1800, 1600, 1250 and 1150 m, respectively. Thus, it is observed that the gamma-gamma model shows better performance than the log-normal turbulence model as the former can perform more effectively under correlation as opposed to other fading channel models. Figure 4: Measured BER at fixed MMF link of 100 m under clear air conditions. (**a**) Users 1 to 4 operating on Donut mode 0, (**b**) users 5 to 8 operating on Donut mode 1.
# Device-To-Device Communication in 5G Environment: Issues, Solutions, and Challenges
## 7 Challenges in D2D Communication
### Challenges in Power Control
#### 7.4.2 Optimal Transmission Power  
Making sure that the transmission power of D2D devices is well maintained is extremely crucial. For example, the transmission power should not be too low in order to attain a superior quality of D2D links [90]. There are certain requirements to minimize the transmission power if the users want to obtain higher battery life for the equipment. Researchers are interested in the area where the transmission power is set to the optimum because the power allocation can be divided into dynamic and static power allocation. For static power allocation, the transmission power is static and does not change with any situation. However, for the dynamic power allocation, the transmission power is flexible and can be changed depending on the proximity between the devices. In the case of uplink transmission, power management plays an essential part in minimizing the co-channel interference and near-far effect [91]. The QoS of the cellular users can be maintained if the upper power level is set to the D2D users in the network. Mitigating interferences in underlaying D2D cellular networks can be done using an effective power control method. There is a constant need to determine the D2D link optimum power level to minimize the interference and maintain the link quality.
# Aerodynamic Analysis of Simple Grider Bridges under Construction Phase
## 4 Discussion  
The importance of long-wind vibrations produced by vortex shedding seems to be the most crucial conclusion among all achieved results. The tall and thin shape of the beam cross-section leads to significant drag dynamic effects in the same order of magnitude as lift oscillations. Considering that the bending stiffness of the beams is considerably lower in the horizontal direction, the dangerous effects are the ones in the along-wind direction. A lower stiffness implies higher amplitudes and lower frequencies of vibration, meaning more vulnerability to dynamic effects. Furthermore, the frequency of the vortex shedding loads in the along-wind direction is twice the one in the cross-wind direction. The methods proposed by Eurocode to evaluate dynamic-wind response in the along-wind direction can be applied using only the drag coefficient. However, they do not include vortex shedding loads in this direction. The methods proposed for vortex shedding evaluation only consider cross-wind vibrations. Thus, it would be necessary to study the along-wind vibrations induced by vortex shedding and adapt the analytical methods if required.  
It was observed that the structural system is more vulnerable when only one beam is installed. Usually, this construction stage lasts only for a few days, so high winds' risk is lower. Nevertheless, the wind can severely damage the bridge if the first beam is erected when the flow velocity is near the critical vortex shedding wind speed.  
When both beams are mounted, there are different solutions to reduce the wind effects on the structure. First, increasing the beams' distance is a simple solution if the project is still in the design stages. Unlike other geometrical modifications, this variation does not change the vertical bending stiffness of the bridge. Therefore, the changes could be made without redesigning the complete structure. Second, closing the section with wood or steel slabs is an effective solution to reduce wind effects before the concrete slab has been built. The Strouhal number reduction implies higher critical wind speeds with lower probabilities of occurrence. Furthermore, this solution leads to a considerable decrease in the along-wind dynamic effects caused by vortex shedding. Although cross-wind effects increase at the same time, it is rather unlikely that the low frequency of the cross-wind vortex shedding load could match the high frequency of the structure in this direction.  
In general, all the simulations done describe the overall aerodynamic behavior of simple girder bridges under construction with the studied cross-section. The study highlights  
Figure 12: Distribution of the Strouhal number, drag coefficient, and Root Mean Square values of the drag and lift coefficients with and without the wooden/steel slabs isolating the space between beams (double column, B&W in the printed version).  
the potentially dangerous wind-induced actions during these bridges' construction, and gives qualitative data to use in design stages and future research.
## 2 Materials and Methods
### Theory
#### 2.1.4 Clutter Filtering  
Prior to estimating velocity, a clutter filter is typically used to suppress stationary components of the slow-time signal. Traditionally this is accomplished with a high-pass filter. In the case of HRIs, the PSF of each frame is the same and, therefore, clutter filtering may be handled with standard digital filtering techniques [15]. However, because the PSF in each LRI frame varies with time, the options for clutter filtering become more varied. If we wish to only compare images with the same PSF during the clutter filtering process, we must separate our slow-time signal into polyphase channels with the same steering angle and process them independently. This separation results in \(N_{T}\) different polyphase channels operating at a slow-time sampling rate equivalent to that of the HRIs. Using the principles of multirate signal processing, one can show that compounding the LRIs after filtering this way will result in the same digital frequency response as a simple clutter filter on the HRIs (see Theorem A2 in the Appendix). This result is a direct consequence of one of the noble identities of multirate signal processing [14].  
It is important to note that using such a filtering scheme comes with some significant drawbacks. Because the clutter filtering occurs at the HRI frame rate, the frequency response of the filter repeats \(N_{T}\) times when analyzed with respect to the LRI frame rate. This results in stop bands occurring at integer multiples of the HRI frame rate. Therefore, velocity estimates within these slow-time bands will be less consistent than at other frequencies.
###### Abstract  
In this study, a joint modulation format identification and optical signal-to-noise ratio (OSNR) monitoring algorithm is proposed and experimentally demonstrated using the k-nearest neighbor algorithm for intensity modulation and direct detection (IMDD) orthogonal frequency division multiplexing (OFDM) systems. A modified amplitude histogram of received signal is employed to serve as the classification feature to simplify the computation. Experimental results show that five common quadrature amplitude modulation (QAM) modulation formats, including 4-QAM, 16-QAM, 32-QAM, 64-QAM and 128-QAM, can be identified under 100% accurate estimation at the received optical power of \(-11\) dBm. Robustness of the proposed scheme to constellation rotation is also experimentally assessed. At the same time, system OSNR monitoring also can be achieved and the average prediction mean square error (MSE) is 0.69 dB\({}^{2}\), which is similar to that using an artificial neural network. Computational complexity assessment demonstrated that similar performance but less computing resource consumption can be achieved by using the proposed scheme rather than the artificial neural network-based scheme.  
k-nearest neighbor algorithm; modulation format identification; OSNR monitoring +
Footnote †: journal: Applied Sciences
###### Abstract  
In this paper, we investigate mechanisms for improving the quality of communications in wireless-optical broadband access networks (WOBAN), which present a promising solution to meet the growing needs for capacity of access networks. This is achieved by using multiple gateways and multi-channel operation along with a routing protocol that effectively reduces the effect of radio interference. We present a joint route and channel assignment scheme with the objective of maximizing the end-to-end probability of success and minimizing the end-to-end delay for all active upstream traffic in the WOBAN. Performance evaluations of the proposed scheme are presented using ns-2 simulations, which show that the proposed scheme improves the network throughput up to three times and reduces the traffic delay by six times in presence of 12 channels and four network interface cards (NICs), compared to a single channel scenario.  
optical networks; wireless mesh networks; access networks; quality-aware routing; channel assignment; genetic algorithms Article
## 2 Systematic Literature Review (SLR)
### SLR Result and Findings
#### 2.2.2 Biometric Trait  
Biometric-based authentication systems utilize a variety of biometric traits, including physiological and behavioral characteristics such as the face, FP, iris, FV, and palmprint, and, occasionally, additional modalities such as gait and voice. Each modality was investigated for its distinct capability of accurately identifying individuals and enhancing the security of the system.  
Our review revealed that face recognition is the most extensively studied biometric trait, appearing in twenty studies. This is followed by fingerprint recognition, which was cited in fourteen studies. Iris recognition appeared in thirteen studies, while finger vein (FV) and palmprint were discussed in eleven and eight studies, respectively. Table 2 provides a summary of the distribution of these biometric traits across the reviewed studies that focused on biometric-based recognition systems.  
This review underscores the predominant emphasis on facial and fingerprint recognition as the primary modalities in current biometric research. Concurrently, there is growing interest in integrating additional traits, such as iris, finger vein, and palmprint recognition, to enhance the accuracy, robustness, and security of authentication systems. Moreover, some studies have augmented public datasets with self-collected biometric data to more accurately simulate real-world application scenarios and address dataset limitations, thereby further enriching the methodological diversity within the field.
# Predictive Power Management for Wind Powered Wireless Sensor Node
## 2 Motivation and Related Work
### Predictive Energy Management  
[PERSON] et al. proposed a predictive wake-up power manager for wireless nodes powered by periodic energy sources [14]. The main improvement was that the average number of wake-up variations has significantly reduced. [PERSON] et al. presented a gradual power manager for EH-WSN powered by pseudo-periodic energy sources [15], it was able to supply high average throughput while maintaining a low throughput variability with respect to time. Paper [16] investigated how to design a wireless powered sensor network with minimal power requirements optimally: it formulated an optimization problem to minimize the total energy consumption at two remote radio units by jointly optimizing the energy beam forming and the time assignment.  
In general, existing energy managements can be categorized into two main types: non-predictive and predictive. Non-predictive scheme assigns workload according to the residual energy of the storage device. As a conservative way of workload assignment, low energy utilization is ordinary. On the contrary, the innovation of ambient energy predictor has made it feasible to anticipate and pre-allocate the future incoming energy. Thus, the predictive energy allocation algorithm obviously supports higher energy consuming rate comparing with the non-predictive allocation algorithm. However, it has more power failure risk at the meantime, in fact energy predictor is error prone in practical deployment and its working applicability is affected by many factors, such as temperature, humidness and gas composition, etc.: If it ever predicts the incoming energy, the power allocation mechanism will assign a higher power consumption rate to the node, which potentially leads to power failure of the system.
# Synchrotron X-ray Radiation (SXR) in Medical Imaging: Current Status and Future Prospects
## 3 Synchrotron X-ray Radiation in Medical Imaging
### Bone and Joint Imaging  
SXR has been used in bone research to analyze bone aging, disease, and factors that affect bone fragility and resistance. SXR micro CT is considered powerful as it features both biological mechanisms and control of bone quality. It can quantify thousands of lacunar volumes in 3D, which is followed by quantification and visualization for controlling matrix mineralization. All of these result in a change in bone quality and toughness. SR micro CT has shown effective results in the following bone-related studies.
## 3 Description of the Test Cases  
Validation is carried out against measured data from a wind tunnel test campaign, conducted at Politechnico Di Milano (Polimi) [11]. The test campaign concerns a helicopter hovering at varying distances above the ground (pure ground effect). The helicopter rotor is a four bladed one with diameter of 0.75 m. Blades are formed by NACA0012 un-tapered, untwisted airfoil sections with chord length of 0.032 m. The collective pitch was set at 10 degrees, the rotational speed at 2580 RPM and the tip Mach is equal to 0.3. The test matrix of the experiment and the simulations concern steady hover flight above the ground at different altitudes, starting from \(Z/R=1\) and going up to \(Z/R=4\) and zero wind (vertical sweep). Besides measured data-sets, predictions of the HoPFlow code are also compared to results from a previous numerical study conducted with the potential free wake solver GenUVP [13].  
In the HoPFlow simulations, the blades are modeled as actuator lines embedded in a CFD grid of 60,000 cells (see Figures 4 and 5), while the fuselage and the rotor hub are not considered. The ground is simulated as a viscous wall over which a CFD grid of 1,000,000 cells is defined with the a first cell height of \(2\times 10^{-4}\) m (Figure 6). The flow is considered laminar because of the moderate low velocities and Re numbers. The selection of the numerical parameters of the grid spacing has been derived from previous work [16; 23]. The rest of the flow domain (between the rotor and the ground level) is filled with 2,904,000 particles. The flow velocity is determined by the PM method in which re-meshing is applied at every time step. Finally, the time step chosen corresponds to \(1^{\circ}\) azimuth angle.  
Figure 4: CFD meshes surrounding the rotor blades. Red lines represent the blades.  
Figure 3: Spatial distribution of the E- particles. (**Left**): One E-cell is shown within a \(4\times 4\) stencil of the PM grid corresponding to the \(M4^{\prime}\) projection function. There are four \(P_{E}\) particles in the E-cell marked as blue circles. (**Right**): A part close to the solid boundary is shown. On \(S_{B}\), surface particles are shown as blue open circles. The middle surface particle is embedded in the \(M4^{\prime}\) stencil activated for its projection.
# A Connected and Autonomous Vehicle Reference Architecture for Attack Surface Analysis
## 8 Conclusions  
In this paper we have presented a reference architecture from a hybrid functional-communication viewpoint. This combined viewpoint allows easier attack surface analysis as the components and their interactions can be analysed from a single diagram. This reference architecture has been designed with four key sub-architectures for CAVs, the Edge, the Cloud and Devices & Peripherals. The latter three are key to understanding the attack surface of a CAV, because they present new attack vectors that have previously been hard to specify. Finally, two examples of how to instantiate the reference architecture and analyse that instantiation have been provided showing how new and existing attacks can be analysed using this reference architecture.  
Conceptualization, C.M.; Methodology, M.B., K.G. and A.T.L.; Formal Analysis, A.T.L.; Writing--Original Draft Preparation, M.B., K.G. and A.T.L.; Writing--Review & Editing, M.B., K.G., A.T.L., and C.M.; Visualization, M.B. and A.T.L.; Supervision, C.M.; Project Administration, C.M.; Funding Acquisition, C.M.  
This work is supported by the Alan Turing Institute under EPSRC grant EP/N510129/1, the UK Hub for Cyber Security of the Internet of Things, PETRAS, under grant (EP/N02334X/1) and the CAPRI project under grant (TS/P012264/1).  
The authors would like to thank [PERSON] for assistance proofreading this work.  
The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the result.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} AD & Autonomous Driving \\ CAN & Controller Area Network \\ CAV & Connected and Autonomous Vehicles \\ DoS & Denial of Service \\ DDoS & Distributed Denial of Service \\ DSRC & Dedicated Short-Range Communications \\ ECU & Electronic Control Unit \\ GNSS & Global Navigation Satellite System (such as GPS, GLONASS, Galileo and BeiDou) \\ ITS & Intelligent Transport Systems \\ LIDAR & Light Detection and Ranging (detects object distance using light) \\ MiTM & Man-in-the-Middle \\ RCE & Remote Code Execution \\ \end{tabular}
# Fault Analysis and Protection Principle for the Distribution Networks Integrated with PV and BESS
## 2 Fault Characteristics of the Distribution Networks with PV and BESS  
The structural diagram of a distribution network at a certain location in Tianjin connected with PV and BESS is shown in Figure 1. Due to the connection of PV and BESS, the traditional single source radial distribution network has transformed into a complex network with dual power sources or even multiple power sources. Therefore, for a transmission line with dual power sources, the overcurrent relay on the side of the inverter interfaced resource (IIR) requires a directional element to form a directional overcurrent relay [21], such as PR4. Since PV and BESS belong to the IIR category, and the fault characteristics of PV and BESS are significantly different from those of synchronous power sources, the traditional power distribution element either malfunctions or refuses to operate. To solve this problem, this section analyzes the fault characteristics when a symmetric fault or asymmetric phase-to-phase fault occurs in a distribution network at a certain location in Tianjin connected with PV and BESS. Table 1 shows the specific parameters of the system: