esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Novel Vehicle Terminal Based on Acoustic Communication Technology
### Acoustic Demodulation Module
#### 3.2.4 Other Modules  
In order to realize the communication between the management platform and the vehicle terminal, the developed vehicle terminal integrates the GPRS wireless communication module, which makes it possible to control the vehicle access remotely and monitor the vehicle operation data in real-time.  
GPS module provides the vehicle's location and timing information, and transmits it to the management platform in real time.  
The power-supply module not only acts as a voltage conversion, but also plays a supporting role in standby power. Through the OBD interface from the CAN bus to obtain the required power of the vehicle terminal is the main power supply method. However, in practice found that if the electric vehicle is in a dormant state, the battery power will be gradually depleted. In order to avoid the sudden situation of losing battery power, the power module is added as an auxiliary buffer. Once the power supply module is activated, a battery failure warning will be sent to remind the operation and maintenance personnel in time.
# Handover Decisions for Ultra-Dense Networks in Smart Cities: A Survey
## 2 Background
### Handover Concept  
Mobile network handover is the act of moving a subscriber from one base station to another to maintain continuous connectivity. It involves measurement of signal quality metrics, comparison with predetermined thresholds, and selection of the best base station to be connected to. Handover can be network-initiated or user-initiated based on the application scenario. There are several types of handover: hard handover, soft handover, and predictive handover. Modern networks employ smart algorithms that consider not only signal strength but also network congestion, device power consumption, and even user behavior [25].  
According to the classical handover procedure in the 3 GPP technical specification, each base station determines a handover margin (HOM) value, which is then communicated to all user equipment (UE). When a piece of UE detects that the Reference Signal Received Power (RSRP) from a neighboring base station surpasses the RSRP of its current serving base station by at least this margin for a predefined period, known as the Time To Trigger (TTT), it generates a measurement report [26]. This report, which includes details on the RSRPs and signal-to-interference-plus-noise ratios (SINRs) of neighboring base stations, is sent to the serving base station to indicate the need for a handover. The serving base station then evaluates this data to select the most suitable target base station for handover, thereby completing the process. However, this algorithm does not impose any restrictions on a UE connecting to an overloaded base station, which can result in suboptimal QoS due to network congestion. To enhance handover decision-making, additional factors such as network load, UE mobility, and energy efficiency should be considered [27; 28].  
Figure 3: Ultra-dense heterogeneous networks in smart cities.  
These considerations add complexity to the handover initiation process, as it must balance multiple parameters for optimal performance [29].
# Underwater Object Detection Method Based on Improved Faster RCNN
## 3 Proposed Method
### Improvement of Bounding Box Mechanism  
#### 3.5.1 Giou  
The IOU is a very commonly used indicator in the object detection process, but the IOU is the concept of ratio; therefore, it does not pay attention to the area size and shape of the object and the bounding box. During the model training process of the object detection algorithm, a large number of bounding boxes will be formed and it is possible that the loss values of the bounding boxes are the same, but there are different IOU values. Therefore, the original IOU has two problems: (1) the prediction range of the bounding box and thereal object do not overlap, the value of the IOU is always 0, and it cannot be optimized; (2) the original IOU cannot discern the different alignments between the bounding boxes and the ground-truth objects.  
In order to solve the above two problems, a few related research has proposed the GIOU algorithm. The GIOU also takes into account the non-overlapping areas of the bounding box and the real object, which can weaken the weakness of the original IOU. This paper replaces the IOU structure in the Faster RCNN algorithm with the GIOU, and the algorithm model can better optimize the bounding box during the training process, thereby improving the performance of the Faster RCNN model.
# Antioxidant Properties of Soybean Oil Supplemented with Ginger and Turmeric Powders
###### Abstract  
Soybean oil has been supplemented with 10% (_w/w_) of ginger and turmeric powders derived from commercial products (GC--commercial ginger and TC--commercial turmeric), freeze-dried rhizomes (freeze-dried ginger (GR) and freeze-dried turmeric rhizome--TR) and peels (freeze-dried ginger peel (GP) and freeze-dried turmeric peel--TP) for developing a functional seasoning with great lipid stability for human consumption. The exhausted ginger and turmeric powders were also recovered and recycled two times to promote a more sustainable process. The antioxidant activity and oxidative stability of oil samples were evaluated respectively by spectrophotometric and Rancimat methods. Folin-Ciocalteu assay and HPLC analysis were also performed to quantify total polyphenols, ginger-derived 6-gingerol and 6-shogaol, and turmeric-derived curcumin. Their antioxidant activity as well as oxidative stability, which non-linearly decreased over cycles because of a strongly reduced phenolic extractability, linearly increased with increasing phenolic yields. Hence, ginger and turmeric can be proposed as healthy spices containing bioactive compounds to control lipid oxidation and improve oil stability. Moreover, the valorization of peels as eco-friendly source of natural antioxidants is a valid strategy for providing added-value to these agro-food wastes.  
lipid oxidation; oxidative stability; Rancimat; natural antioxidants; by-products; phenolic compounds; 6-gingerol; 6-shogaol; curcumin; Zingiberaceae
## 1 Introduction
We can use a laser to illuminate the target for localization. Compared to conventional CCD-based detectors, XS detectors have the capability for a single-photon response, low readout noise and a very low dark count rate. As shown in this work, by using our proposed center of mass algorithm, an XS detector without a high-power laser requirement could provide accurate localization for dark targets. Star sensors with XS detectors can obtain a space vehicle's attitude by detecting the center of mass of stars at different positions. By applying our algorithm to star sensors, we can achieve efficient detection of the space vehicle's attitude.
## 4 Results and Discussion
### Shear Modulus  
Once the \(A\), \(B\) and \(C\) coefficients are obtained, it is possible to use them to derive some properties of the structure, and in particular the shear modulus of the core, \(G_{c}\). Table 4 reports a comparison  
Figure 16: Sound transmission loss for the honeycomb in Figure 15b, predicted assuming an isotropic structure with ‘average’ bending stiffness \(D^{\prime}_{\text{avg}}\) (**a**) and assuming an orthotropic structure with \(\theta\)-dependent apparent bending stiffness \(D^{\prime}_{a}\left(\theta\right)\) (**b**).  
Figure 15: Honeycomb footprint on the laminates: (**a**) slightly-orthotropic material (present work); (**b**) strongly-orthotropic material.  
between the values estimated from the \(B\) coefficient and the average values obtained by product datasheets (see Table 3). An agreement around \(\pm 20\%\) is found.  
The shear modulus of the core can be a problematic parameter to determine experimentally, since standardized tests require the use of a strain-stress test bench and a complex setup. The measurements performed according to ASTM C273/C273M-16 provided results one order of magnitude lower than the expected values, the reasons being:  
* a different sample aspect ratio (5:1) with respect to the standard prescriptions (12:1), an inevitable choice given the characteristics of the test bench;
* the presence of sandwich laminates and adhesive layers, which could not be removed without damaging the core;
* the use of aluminum clamps and plates, whereas the standard requires steel components, because of the technological limits of the available machining equipment.  
All these elements contributed to return an evidently too low shear modulus. The proper arrangement of the measurement equipment and setup turned out to be essential to find reliable results, while a fair estimation based on the natural frequency method and wave propagation approach seems easier to obtain.
## 2 Experimental Setup  
The experimental setup of the BGSe-based OPO is shown in Figure 1. A side-pumped electro-optic Q-switched Nd:YAG laser was adopted as the fundamental 1064 nm pump source. The side pump module was composed of five quasi-CW 808 nm laser diode (LD) arrays and a 148 mm long Nd:YAG rod (0.6% doped). The pulse width of the quasi-CW LD arrays was 200 \(\upmu\)s and the repetition rate was adjustable in the range of 1-1000 Hz. The electro-optic Pockels cell consisted of two BBO crystals with dimensions of 6 mm \(\times\) 6 mm \(\times\) 20 mm. The laser cavity was a plano-plano cavity with a high reflection mirror M1, an output coupler M2, a quarter wave plate and a Brewster polarizer. The output coupler M2 was partial reflection (R \(\approx\) 5%) to avoid laser damage to the crystal rod caused by the high energy intensity in the cavity. The total length of the laser cavity was 350 mm.  
A half wave plate and a Brewster polarizer were combined as an energy attenuator to adjust the pump energy and maintained the polarization direction. An optical isolator was employed to avoid the possible reflected damage to the Nd:YAG laser. The DP-SRO BGSe-OPO was composed of two BaF\({}_{2}\) mirror M3 (1.064 \(\upmu\)m AR and 1.35-1.65 \(\upmu\)m and 3.65-4.50 \(\upmu\)m HR) and M4 (3.65-4.50 \(\upmu\)m AR and 1.064 \(\upmu\)m and 1.35-1.65 \(\upmu\)m HR). The DP-SRO configuration can effectively improve the mid-infrared output and reduce the threshold [22].  
A large-size BGSe crystal (shown in the inset of Figure 1) with dimensions of 8 mm \(\times\) 8 mm \(\times\) 15 mm was used as the nonlinear optical crystal in OPO. The BGSe crystal employed was grown by vertical Bridgman method [23]. In addition, two zone annealing technique was used to improve the optical properties. The BGSe crystal exhibits high transmittance from 0.47 to 18 \(\upmu\)m and low absorption coefficient of 0.042 cm\({}^{-1}\) at 4 \(\upmu\)m. The BGSe crystal was cut at \(\theta\) = 42.5\({}^{\circ}\) and \(\varphi\) = 0\({}^{\circ}\) for Type I phase-matching condition (o-ee). Both sides of the BGSe crystal were well-polished and AR-coated for 1.064 \(\upmu\)m, 1.3-1.6 \(\upmu\)m and 3-5 \(\upmu\)m. The crystal was wrapped in indium foil and cooled to 25 \({}^{\circ}\)C with brass heat sink to reduce the thermal effect in BGSe crystal. The wavelength of the signal wave was measured by a spectrometer (Agilent, 86142B, Santa Clara, CA, USA), which was used to calculated the wavelength of the generated mid-infrared wave. A dichroic BaF\({}_{2}\) mirror (3.65-4.50 \(\upmu\)m AR and 1.064 \(\upmu\)m and 1.35-1.65 \(\upmu\)m HR) was used as the long-wave pass filter. The energy of the generated mid-infrared wave was measured by a mid-infrared energy detector (Newport corporation, 919E-0.1-12-25K, Irvine, CA, USA).
# Microcontroller Unit-Based Wireless Sensor Network Nodes: A Review
## 2 Wireless Sensor Node: An Overview
### Communication Sub-System  
The communication subsystem comprises a radio module or transceiver for facilitating the reception and transmission of signals to and from the wireless sensor motes, and also to a base station or sink [14]. Radio frequency (RF) communication is suitable for WSNs because it is not limited by line-of-sight (LOS) and recent advances allow the utilization of low-power radio modules with data rates and communication ranges adjustable depending on the application scenarios.
## 3 Calibration of System Parameters
### Orientation of the Mirror  
A mirror with a matrix of discrete hollow ring markers on its surface was used to determine the distance between the reference plane and the two LCD screens in orientating the reference plane in the camera coordinate system. After the mirror plane was adjusted to be parallel to the screen surface, the CCD camera captured an image of the hollow ring marker matrix, as illustrated in Figure 2a.  
After extracting the inner and outer edges of each ring marker, the center of each of the markers was determined using the principles of cross ratio and the pole-polar relationship [41]. Figure 2b shows the center positions determined for each marker in the matrix, illustrated by red dots. Because the distance between neighboring ring markers is known beforehand, the external parameters of the mirror, rotation matrix R, and translating vector T could be obtained in the camera coordinate system to define the orientation of the mirror [42].  
Obviously, the location accuracy of each center position was the most influential factor in the above process, and had an effect on determining the orientation of the mirror. This paper used [PERSON]'s [30] method to calculate the real projection center to reduce the error as much as possible, this method is more accurate and stable than using the ellipse fitting method, as the radius of inner circle increases.
###### Abstract  
The composite powders composed of red mud (RM) and NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\) (NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM) were successfully prepared by the anti-solvent method. The composition and structure of the NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM composite powders were characterized by the techniques of X-ray diffraction (XRD), SEM, N\({}_{2}\) adsorption-desorption and Thermogravimetry-Differential scanning calorimetry (TG-DSC). The analysis results indicate that the as-prepared samples are composed with uniform nanoparticles and possess the porous structure. The methane explosion suppression characteristics of the NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM composite powders were tested by a 20 L spherical explosion system and a 5 L pipe test system. The results show that the NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM composite powders possess considerable suppression properties on methane explosion. When the loading content of NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\) reached 30%, the maximum pressure and the maximum pressure rise rate of methane explosion were decreased by 35.1% and 95.8%, respectively. When comparing with no powder addition, the time to reach the pressure peak was extended from 0.07 s to 0.50 s. The NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM composite powders presented a synergistic suppression effect between NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\) and RM, which made it exhibit considerable suppression property than that of pure NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\) or red mud powders.  
Keywords:NH\({}_{4}\)H\({}_{2}\)PO\({}_{4}\)/RM composite powders; methane explosion; suppression characteristics; synergistic suppression effect +
Footnote †: journal: Applied Physics
# A Practical Implementation of Post-Quantum Cryptography for Secure Wireless Communication +
###### Abstract  
Recent advances in quantum computing have prompted urgent consideration of the migration of classical cryptographic systems to post-quantum alternatives. However, it is impossible to fully understand the impact that migrating to current Post-Quantum Cryptography (PQC) algorithms will have on various applications without the actual implementation of quantum-resistant cryptography. On the other hand, PQC algorithms come with complexity and long processing times, which may impact the quality of service (QoS) of many applications. Therefore, PQC-based protocols with practical implementations across various applications are essential. This paper introduces a new framework for PQC standalone and PQC-AES (Advanced Encryption Standard) hybrid public-key encryption (PKE) protocols. Building on prior results, we focus on securing applications such as file transfer, video streaming, and chat-based communication using enhanced PQC-based protocols. The extended PQC-based protocols use a sequence number-based mechanism to effectively counter replay and man-in-the-middle attacks and mitigate standard cybersecurity attack vectors. Experimental evaluations examined encryption/decryption speeds, throughput, and processing overhead for the standalone PQC and the PQC-AES hybrid schemes, benchmarking them against traditional AES-256 in an existing client-server environment. The results demonstrate that the new approaches achieve a significant balance between security and system performance compared to conventional deployments. Furthermore, a comprehensive security analysis confirms the robustness and effectiveness of the proposed PQC-based protocols across diverse attack scenarios. Notably, the PQC-AES hybrid protocol demonstrates greater efficiency for applications handling larger data volumes (e.g., 10-100 KB) with reduced latency, underscoring the practical necessity of carefully balancing security and operational efficiency in the post-quantum migration process.  
Keywords:post-quantum cryptography; post-quantum key exchange; public-key encryption; IoT/5G/6G security; application; secure communication; digital signature licenses/by/4.0/. +
Footnote †: These authors contributed equally to this work.
# Shunt Damping Vibration Control Technology: A Review
###### Abstract  
Smart materials and structures have attracted a significant amount of attention for their vibration control potential in engineering applications. Compared to the traditional active technique, shunt damping utilizes an external circuit across the terminals of smart structure based transducers to realize vibration control. Transducers can simultaneously serve as an actuator and a sensor. Such unique advantage offers a great potential for designing sensorless devices to be used in structural vibration control and reduction engineering. The present literature combines piezoelectric shunt damping (PSD) and electromagnetic shunt damping (EMSD), establishes a unified governing equation of PSD and EMSD, and reports the unique vibration control performance of these shunts. The schematic of shunt circuits is given and demonstrated, and some common control principles and equations of these shunts are summarized. Finally, challenges and perspective of the shunt damping technology are discussed, and suggestions made based on the knowledge and experience of the authors.  
shunt damping; shunt; vibration control; piezoelectric; electromagnetic +
Footnote †: journal: Applied sciences  
_Applied Sciences_
## 5 Results  
### Simulation Setup  
The following table lists the parameters used in the computer simulation of the system (Table 2).  
In this work, the PU signal is a 4-QAM modulated OFDM signal with rectangular pulse shaping filter. The FFT size for the PU-OFDM is chosen to be 32 samples, with corresponding CP size 8 samples. The same parameters for the SU-FC-FB signal are 128 and 32 respectively. It is assumed that the SU transmitter performs spectrum sensing before scheduling its transmission. It superimposes its transmission on consecutive PU-bands of size 32 FFT bins, where the IT threshold is not exceeded. The cyclic frequency set chosen, corresponding to the PU-OFDM signal, is \(\{0,\,\frac{3}{40},\,\frac{-3}{40}\}\), where each non-zero cyclic frequency is not a multiple of that of the SU-FC-FB signal. The cyclic frequency set chosen for the SU-FC-FB is \(\{\frac{\pm 3}{160},\,0,\,\frac{\pm 1}{160}\}\).  
A 2-layer DDA is selected, where the number of input neurons of the 1 st auto-encoder layer is 640, while the numbers of hidden neurons in 1 st and 2 nd auto-encoder layers are 196 and 20 respectively. The number of iterations performed by the FRESH equalizer, for repeated interference estimation and subtraction, is 3. Out of 10000 samples used, the first 2000 samples are used as online training  
Figure 3: Cyclic FRESH filtering based SIC decoding in proposed NOMCR system.  
data for the DDA-FRESH system. The remaining samples are used for the interference estimation and separation. 2 injection levels, \(-5\) dB and \(-10\) dB, are adopted in this work. This means that the SU-FC-FB signal is 5 dB and 10 dB lower in power than the PU-OFDM signal.
## 3 Results  
### Response of Plant Functional Composition and Species Diversity to Experimental Maniuplation  
Analysis of the vegetation cover data indicated that plant communities at both sites had diverged as a result of the experimental manipulation of water tables, temperatures, and CO\({}_{2}\) levels. At APEX, the most striking trend was the overall higher percent cover of litter and reduced cover of nearly all other PFTs in the lowered water table treatment as compared with the control and raised water table treatments (Table 3, Figure 5). Sedges, equisetum, fobs, and shrubs all showed trends towards higher abundance in the control treatment, and mosses were significantly more abundant in the control than other treatment (Table 3). At SPRUCE, we found a trend towards greater shrub cover with warming, coinciding with a decrease in forb cover (Figure 6, Table 4). Graminoid species remained fairly consistent across the treatments (Figure 6).  
Our analysis of diversity also showed a trend towards greater alpha diversity in the control treatment as compared to the raised or lowered treatments at APEX (ANOVADiversity F\({}_{2,10}\) = 3.52, p = 0.07) (Figure 7). We did not find any trends in plot-level diversity with warming or CO\({}_{2}\) level at the SPRUCE site (Table 3).  
Figure 6: Percent PFT cover in response to warming at the SPRUCE project. Linear mixed effects models were fit to the PFT data with temperature as a continuous variable, CO\({}_{2}\) level as a factor, and chamber included as random effect.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**PFT** & **Marginal R\({}^{2}\)** & **Conditional R\({}^{2}\)** & **AIC** & \(\beta_{\text{TEMP}}\) & \(\beta_{\text{CO2}}\) & \(\beta_{\text{TEMP-CO2}}\) \\ \hline Forb & 0.278 & 0.605 & 342 & \(-\)4.444 & \(-\)6.143 & 1.170 \\ Sedge & 0.017 & 0.153 & 412 & 0.758 & 15.178 & \(-\)3.484 \\ Strub & 0.155 & 0.251 & 407 & \(-\)9.932 & \(-\)28.633 & 12.935 \\ Diversity & 0.023 & 0.285 & \(-\)37 & \(-\)0.003 & 0.024 & \(-\)0.005 \\ \hline \hline \end{tabular}
\end{table}
Table 4: SPRUCE linear mixed effects model results for the response of cover to warming and CO\({}_{2}\) level, with chamber added as an error term.  
Figure 7: Shannon alpha diversity in response to treatment at APEX. Boxes represent the interquartile range, the central black bar indicates the treatment mean, and error bars represent standard deviation. Number of plots included per treatment: control = 5, lowered = 4, raised = 4.