esa-sceva/satcom-chunk-collection huggingface dataset:
# Spoofing Detection Algorithm Based on Pseudorange Differences
###### Abstract  
Intentional spoofing interference can cause damage to the navigation terminal and threaten the security of a global navigation satellite system (GNSS). For spoofing interference, an anti-spoofing algorithm based on pseudorange differences for a single receiver is proposed, which can be used to detect simplistic and intermediate spoofing attacks, as well as meaconing attacks. Double-difference models using the pseudorange of two adjacent epochs are established followed by the application of Taylor expansion to the position relationship between the satellite and the receiver (or the spoofer). The authenticity of the signal can be verified by comparing the results of the proposed spoofing detection algorithm with the traditional least squares method. The results will differ when spoofing is present. The parameter setting of the proposed algorithm is introduced. The algorithm has the advantage of both simplicity and efficiency and needs only a single receiver and pseudorange data. A NovAtel receiver is adopted for the actual experiments. The Texas spoofing test battery (TEXBAT), as well as two other simulation experiments are used to verify the performance of the algorithm. The simulation results validate the feasibility and effectiveness of the algorithm.  
single receiver; meaconing attack; simplistic attack; intermediate attack; anti-spoofing technology; pseudorange difference
###### Abstract  
Objective: The purpose of this study was to assess the impact of photopolymer resin type, arch location, and post-processing techniques on the trueness and precision of three-dimensionally printed (3 DP) full-arch surgical implant guides. Methods: Stereolithography reference images of an upper and lower surgical guide with six drill holes from a full-mouth rehabilitation clinical case were used. The files were imported into the Asiga MAX UV slicing software (Asiga Composer) where build orientation, print resolution, and support structures were added. A digital light processing 3D printer (MAX UV, Asiga Max) was used for printing the samples. The samples assessed were printed using two different, manufacturer-validated resins, DentaGuide (\(n=35\)) and DentaClear (\(n=20\)). The samples were subdivided and measured based on the post-processing technique used: handwashing (\(n=20\)), sonication (\(n=25\)), a mix of handwashing and sonication (\(n=10\)), and post-curing using 385 nm UVA light with nitrogen (\(n=50\)) or without nitrogen (\(n=5\)). The diameter of each drill hole per guide was measured using a coordinate measuring machine (Absolute Arm 7-Axis, Hexagon) and compared with the reference STL to calculate each sample's trueness (median error) and precision (interquartile range). The Mann-Whitney and Kruskal-Wallis tests were used for statistical analyses. Results: All samples demonstrated a dimensional error of <70 \(\upmu\)m. No significant differences (\(p>0.05\)) were observed between upper and lower arches and between post-processing techniques using nitrogen, irrespective of the use of hand- or ultrasonic washing. In contrast, DentaClear resin was significantly (\(p<0.001\)) more accurate with a trueness of 26 \(\upmu\)m and precision of 12 to 34 \(\upmu\)m versus the DentaGuide at \(-31\)\(\upmu\)m and \(-54\) to \(-17\)\(\upmu\)m, respectively. The samples post-cured without nitrogen were significantly (\(p<0.05\)) the least accurate of all surgical guides, with a trueness of \(-42\)\(\upmu\)m and precision of \(-68\) to \(-39\)\(\upmu\)m. Conclusion: The resin type and nitrogen post-processing are parameters that can significantly impact the accuracy of surgical guides. The tolerance of 3 DP surgical guides needs to account for the dimensional changes occurring during the manufacturing process to minimise implant positioning errors.  
3D printing; full-arch surgical implant guides; post-processing technique; accuracy; trueness; precision +
Footnote †: journal: Applied Sciences
# Efficient SMC Protocol Based on Multi-Bit Fully Homomorphic Encryption
## 1 Introduction
Therefore, to solve the problems mentioned above, a three-round secure multi-party computation protocol that can resist malicious opponents under the CRS model is designed in this paper with the help of the New Fully Homomorphic Encryption (NFHE) scheme [18] and threshold decryption. This protocol supports multi-bit encryption. In addition, compared with the existing secure multi-party computation protocol under the CRS model, the ciphertext size of the protocol is smaller, and the overall performance is better than the existing protocol.
# A Review of Prediction Methods for Ultra-Low Cycle Fatigue Damage of Steel Piers Under Earthquakes
## 2 Research Status and Development Trend at Home and Abroad
### Continuum Damage Mechanics (CDM) Model  
The CDM model is the third method for predicting ultra-low cycle fatigue damage in steel structures. This model describes the macroscopic mechanical behavior of materials and the evolution of damage by utilizing appropriate damage variables. Unlike empirical formula methods, the CDM model can take stress triaxiality into account and predict the ultra-low cycle fatigue life of welded joints under complex stress states. Additionally, compared to the CVGM, which is grounded in microscopic damage mechanisms, the CDM model requires fewer calibration tests. It also results in less variability in calibrated parameters. CDM can directly factor in the effects of damage on material constitutive behavior and integrates easily with finite element software, enhancing its practical applications [69].
# Proof-of-Concept of a Millimeter-Wave Integrated Heterogeneous Network for 5G Cellular
###### Abstract  
The fifth-generation mobile networks (5G) will not only enhance mobile broadband services, but also enable connectivity for a massive number of Internet-of-Things devices, such as wireless sensors, meters or actuators. Thus, 5G is expected to achieve a 1000-fold or more increase in capacity over 4G. The use of the millimeter-wave (mmWave) spectrum is a key enabler to allowing 5G to achieve such enhancement in capacity. To fully utilize the mmWave spectrum, 5G is expected to adopt a heterogeneous network (HetNet) architecture, wherein mmWave small cells are overlaid onto a conventional macro-cellular network. In the mmWave-integrated HetNet, splitting of the control plane (CP) and user plane (UP) will allow continuous connectivity and increase the capacity of the mmWave small cells. mmWave communication can be used not only for access linking, but also for wireless backhaul linking, which will facilitate the installation of mmWave small cells. In this study, a proof-of-concept (PoC) was conducted to demonstrate the practicality of a prototype mmWave-integrated HetNet, using mmWave technologies for both backhaul and access.  
5G cellular networks; millimeter wave; heterogeneous networks; flexible backhaul +
Footnote †: journal: Sensors
## 2 Materials and Methods
### Algal Strain and Pre-Culture Conditions  
One algal strain used for ADPE remediation was isolated from the waterbody in a peripheral ditch surrounding Mailyuan Landfill Plant, Nanchang City, Jiangxi Province, China, which was named Nanchang University (NCU)-39, and identified using our previous methods [28]. The genomic DNA of microalgae was extracted using the Qiagen DNeasy Plant Mini Kit (Qiagen, Germantown, MD, USA) according to the manufacturer's instructions. Polymerase chain reaction (PCR) was conducted to amplify the extracted 18s rRNA gene. The amplified 18s RNA gene sequences were aligned and compared with the identified microorganisms in the GenBank database (National Center for Biotechnology Information). Based on sequence similarity (Table S3) and phylogenetic (Figure S1) analysis, NCU-39 was identified as a strain of _Chorella pyrenoideas_, which has been widely applied for the remediation of wastewater (including ADPE), because it can grow in a mixotrophic mode to achieve high biomass production and nutrient removal [29]. As the growth rate and plateau level of NCU-39 in Tap medium (Table S4) containing the abundance of organic acetic acid were quite higher than those in BG11 medium (Table S5) containing inorganic Na\({}_{2}\)CO\({}_{3}\) (Figure S2), NCU-39 as a mixotrophic strain can be used for ADPE remediation.  
NCU-39 was maintained in Tap medium (Table S4) and pre-cultured with 200 mL working volume in a 500 mL flask. The algae were incubated at \(28\pm 1\)\({}^{\circ}\)C with a continuous light intensity of 5000 lux in a growth cabinet (GTOP, TP, Hangzhou, China).
## 4 Experimental Results and Discussion  
To verify the effectiveness of the maneuvering target tracking of the proposed CPIMM-NAUKF, numerical simulations and practical experiments are both conducted. For the numerical simulation, two sets of experiments were simulated: (1) the standard IMM [9] and CPIMM algorithms; (2) the IMM-UKF [43], IMM-NAUKF connecting the standard IMM with NAUKF, CPIMM-UKF connecting the CPIMM with standard UKF, and CPIMM-NAUKF algorithms. The experimental environment was set as Intel i7 computer with 4-core, 64-bit, 2.4 GHz, 8 GB RAM, and MATLAB R2013a software. For the practical experiments, an integrated navigation system and a synthetic aperture radar (SAR) tracking system using the CPIMM-NAUKF algorithm are, respectively, shown to test the proposed method with real data.
# On Connectivity and Energy Efficiency for Sleeping-Schedule-Based Wireless Sensor Networks
## 3 Connectivity and Energy Efficiency Algorithm
### The Connectivity via Probability Theory
}-\frac{\left(N\frac {\pi R^{2}}{S}\right)^{K+b}}{(K+b)!}=0\). Then \(\left(N\frac{\pi R^{2}}{S}\right)^{a+b+1}=\frac{\left(K+b\right)!}{(K-a-1)!}\). Then \(N=\frac{S}{\pi R^{2}}[\frac{\left(K+b\right)!}{(K-a-1)!}]^{\frac{1}{a+b+1}}\). \[N=\frac{S}{\pi R^{2}}[\frac{\left(K+b\right)!}{(K-a-1)!}]^{\frac{1}{a+b+1}} \tag{6}\]  
It can be seen from the above calculation, when the monitoring area \(S\) and the node communication radius \(R\) are confirmed, the number of nodes \(N\) take the result of Equation (6), which results in the network connectivity probability being the largest in the interval \([K-a,\ K+b]\). Additionally, according to Equation (6) we can obtain the number of nodes \(N\) of the maximum network connectivity probability.
# Performance Analysis of Time Synchronization Protocols in Wireless Sensor Networks
## 5 Evaluation Result  
### Effect of Message Delay Jitter  
The term _message delay_ is defined as the time elapsed from when a node starts transmitting a message until the receiver finally processes it. This amount of time is accumulated by all nondeterministic delays (e.g., channel access, interrupt handling, and propagation) and the deviation in deterministic delays. Message delay is inevitable in network communications. However, it is difficult to determine or estimate the total delay time exactly. Consequently, the message exchange process suffers from variations in delay, known as _message delay jitter_.
# Fine-Grained Detection of Pavement Distress Based on Integrated Data Using Digital Twin
## 5 Results and Discussion
### Comparison of Results for Different Pavement Texture Conditions  
To confirm the effectiveness of virtual data augmentation methods in the detection of pavement defects with different textures, this paper applies virtual data to concrete pavement scenarios and compares the average detection accuracy results. Specifically, concrete pavement defect datasets containing transverse cracks, longitudinal cracks, cross cracks, alligator cracks and potholes are constructed using concrete pavement crack images from the open CrackForest-dataset (CFD) and concrete pavement distress images collected by UAVand are combined with the virtual data generated by the digital twin model according to six virtual-to-real ratios (0:1-5:1) to construct six integrated datasets. Finally, the trained YOLOv5 model was tested on the same 100 images of real concrete pavement distress. The results show that applying the virtual data generated by the digital twin model to concrete pavement distress detection results in a rise in accuracy compared to the detection results without data augmentation, and there is no significant decrease in accuracy compared to the asphalt pavement distress detection results, demonstrating the general applicability of the virtual data augmentation method. The best detection result (MAP of 68.31%) is obtained in the concrete pavement distress test set when the virtual-to-real ratio is 3:1, which is consistent with the above asphalt pavement-distress detection results, demonstrating the generalization of the 3:1 virtual-to-real ratio. The schematic diagram of 5 types of concrete pavement distress is shown in Figure 15, and the MAP for the integrated dataset of six virtual-to-real ratios on concrete pavements is shown in Figure 16.  
Figure 16: MAP for the integrated dataset of six virtual-to-real ratios on concrete pavement.  
Figure 15: Schematic diagram of 5 types of concrete pavement distress. (**a**) Transverse crack. (**b**) Longitudinal crack. (**c**) Cross crack. (**d**) Alligator crack. (**e**) Pothole.
# A Robust Dual-Platform GMTI Method against Nonuniform Clutter
## 2 The Dual-Platform GMTI Method against Nonuniform Environment
### Analysis of the Influence of Heterogeneous Environment in STAP  
The CCM is estimated using the clutter cell near the CUT in STAP, which requires that the training samples have the same statistical characteristics as the CUT when estimating the CCM. When the training samples used to estimate the CUT contain high levels of pollution, hot clutter, and nonuniform power, the CCM estimation will contain errors [29; 30; 31; 32; 33]. The three nonuniformities mentioned above are explained and discussed in the following.
# Lead Monoxide Nanostructures for Nanophotonics: A Review
## 2 Synthesis of PbO Nanostructures
### One-Dimensional PbO Nanostructures  
The 1D PbO nanostructures are fascinating systems, similar to other 1D nanostructure systems (e.g., 1D Te NWs [14], 1D Se nanotubes (NTs) [6], 1D Bi nanobelts [45], 1D ZnO NRs [46; 47], and PtCu NWs [48]), for studying physicochemical properties due to their anisotropic character. For example, a facile alkylamine-mediated thermolysis strategy was reported for the fabrication of high-quality PbO NWs through the thermal decomposition of lead carboxylate in the presence of hexadecylamine (HDA) [49]. The uniform PbO NWs, with an average length of several micrometers and an average diameter of 7.1 nm, were successfully achieved in a high yield (Figure 3a), and closer observation revealed that the as-prepared PbO NWs displayed the nature of a single crystal with a clear lattice fringe of 0.28 nm, which can be assigned to the (200) plane of the \(\beta\)-PbO crystal [49]. Additionally,  
Figure 2: The structural characterizations of 0D PbO NPs. (**a**) SEM image of PbO NPs formed by laser ablation. Reproduced with permission from Reference [42]. Copyright 2019, Elsevier B. V. (**b**) TEM image of PbO QDs prepared by an LPE method (inset showing the HRTEM image of one single PbO QD). Reproduced with permission from Reference [20]. Copyright 2018, The Royal Society of Chemistry. (**c**) TEM image of PbO NPs formed at the water/air interface with the subphase concentration of 1 \(\times\) 10\({}^{-3}\) mol L\({}^{-1}\) at 30 \({}^{\circ}\)C. Reproduced with permission from Reference [44]. Copyright 2011, Elsevier B. V.  
[PERSON] et al. [50] employed porous anodic aluminum oxide (AAO) templates to prepare a PbO NW array by a sol-gel method. The SEM image shows that the as-prepared PbO NWs were successfully grown in the nanochannels of the AAO templates (Figure 3b), and all the NWs parallelly aligned to each other, showing an excellent vertical orientation on the AAO template to form an array (Figure 3b). The average diameter of these as-prepared nanowires is -80 nm, consistent with the channel diameter of the AAO template. Furthermore, [PERSON] et al. [51] successfully synthesized single-crystalline PbO NRs with a hydrothermal approach. The TEM image shows that some NRs are parallel to each other, and that shorter NRs assemble beside the longer ones (Figure 3c). The SAED pattern (Figure 3c inset) shows that the rod-shaped crystal grows along the (100) direction. Because of the size-dependent effect on the performance (the absorption property and bandgap energy (\(E_{\mathrm{g}}\)) [17; 19; 20]), Bi nanostructures with different sizes can be readily synthesized by facilely tuning the reaction conditions (e.g., the reaction temperature and reaction time).
## 4 Results and Discussion
### Comparison of BET and BTT Agent Performances
#### 4.2.2 Agent Trajectory  
The trajectory or agent movement with BET and BTT were observed at every 50 iterations to estimate the trajectory patterns obtained by both controllers. With BET, the 10 agents' movement was scattered during the first 200 iterations, before the agents showed movement heading to the rendezvous point when they reached 200 to 900 iterations. The movement can be seen clearly in Figure 9, in which the agents' state position accumulates within the range of \(x\)-\(y\) coordinates when it reaches 80 \(<x<\) 100 and 70 \(<y<\) 90. This was unlike the BTT system, in which the agents' movement looked consistent, as illustrated in Figure 10. The agents were pulled among one another (Assumption 3) to reach an average consensus while heading to the rendezvous point.
# Wavelength Selection for Detection of Slight Bruises on Pears Based on Hyperspectral Imaging
## 2 Materials and Methods
### Hyperspectral Image Acquisition System  
As shown in Figure 2, the hyperspectral image acquisition system used in this experiment consists of an imaging spectrometer (Imspector V10E, Specim, Oulu, Finland), an imaging lens (OLES22, Imspector V10E), a light source (Fiber Lite Illuminator) equipped with an optical fiber linear lamp, a precision mobile platform, a step-motor and a computer. The imaging spectral region of the hyperspectral imaging system is 380-1030 nm, and the spectral resolution is 2.8 nm. The whole system is placed in a dark box in order to reduce the influence of ambient light.
## 4 Results
### Energy Saving Scenarios  
Figure 10 shows the results from the simulations of the energy saving scenarios proposed for the case study. We analyzed the savings strategies in the figure separately. As can be seen, daylighting control strategy had a highest impact on the total energy consumption in comparison with the other studied strategies. It provided a higher reduction in the annual building consumption by decreasing the energy for lighting in 42% compared with the base case. This strategy exhibited a EUI of 72.09 kWh/m\({}^{2}\)-year. Next, active measures were in second place, providing the highest reduction in energy for HVAC systems and equipment. This is an expected result since active measures directly increased the energy efficiency of the HVAC systems, and also, the replacement of obsolete equipment with their ENERGY STAR equivalent reduced the final energy consumption for equipment in 15%, which can increase if it is applied to other type of buildings such as offices. The resultant EUI of this strategy was 77.07 kWh/m\({}^{2}\)-year. The other saving strategies showed similar percentages of reduction. The main reason why the daylighting strategy had the highest impact among all strategies is due to the exploitation of daylight in the lighting of the building areas. This contribution of daylight to artificial lighting reduces energy consumption considerably compared to the case where there were not dimmable control systems on the light fixtures. Also, the application of all strategies reduces the energy demand for cooling of the building so that there was a reduction in cooling compared to the base case. Likewise, there was a slight reduction in the use of HVAC fans. These results help to estimate how much electrical energy can be saved by implementing these five strategies.  
Figure 11 shows the energy saving percentages and the impact of each energy saving strategy on the total building electricity consumption and cooling. As can be observed, WWR-20% showed the smallest reduction in the annual total energy consumption (only 5.6%) but provided a reduction of about 12% in cooling loads. The solar shading and TrpLoE strategies showed reductions in energy for cooling of around 15-16%. The implementation of the WWR and Daylighting strategies should be carefully analyzed in building modeling. This is because while window reduction also reduces internal heat  
Figure 9: Estimated monthly energy consumption by end-use (authors elaboration).  
gains, this measure primarily affects the input of daylight and natural ventilation. As can be seen, the daylighting strategy showed a reduction of 20%, being the one that provided more savings in annual energy consumption. Despite daylighting controls decrease the energy for cooling in 14.3%, active measures provided a higher saving in cooling load of about 24.2%. In the case of the building under study, the daylighting strategy would be the ideal choice (between the two strategies mentioned) that would represent a considerable energy savings, in this particular case in electricity, and at the same time, a decrease in the energy bills.
## 1 Introduction
Reference [26] proposed a dual modulation strategy of power and data, which was applied to the DC-DC power converter to achieve 'talkative power'. The frequency-hopping differential phase shift keying (FH-DPSK) modulation strategy is used to overcome the crosstalk between the selected transmission systems, and the transmission of '0', '1', '2' and '3' four-bit signals can be realized. However, this method uses cables or lights for information transmission, so the application field is limited. The motivation of this work is to solve the problems of low information transmission rate and output voltage fluctuation in power modulation. A \(M\)-ary amplitude shift keying (MASK) power and information synchronous transmission system based on PSFB is proposed. The PWM variable generated by the pre-transmission modulation signal is directly superimposed on the control end of the MOSFET in the full-bridge inverter to control the phase shift angle of the inverter, thereby changing the voltage amplitude and generating \(M\) amplitude transformations. The power and information are transmitted to the receiving coil at the same time through the transmitting coil, the power is transmitted to the load through the circuit, and the information is restored by the demodulation circuit and DSP. The salient aspects of this paper are that the proposed method reduces the system's volume without a DC-DC modulation circuit, reducing the influence of passive devices on the system and improving the baud rate of the system. At the same time, it transmits data with higher bit width, as 8-ary and 16-ary data, thereby increasing the information transmission rate to four times. The MASK modulation is adopted, and the electric power does not interfere with the signal. The designed demodulation circuit is combined with DSP to control the voltage amplitude fluctuation at the receiving end at 5% to minimize the influence of fluctuation on the load. Section 2 analyzes the system topology and mathematical model. In Section 3, the information modulation and demodulation methods are proposed, and the problems of power transmission efficiency and power, information transmission rate, and interference between information and power are analyzed. Section 4 verifies the feasibility of the method through experiments and simulations. Section 5 concludes the paper.