esa-sceva/satcom-chunk-collection huggingface dataset:
# Inhomogeneous Illumination Image Enhancement Under Extremely Low Visibility Condition
## 2 Materials and Methods  
### Theory  
#### 2.1.1 Low Visibility Imaging Model  
The optical process through scattering media is described in [26]. Due to the scattering effects, the reflected light from the object is divided into the ballistic light, the snake light, which is slightly scattered, forms the noise component of the passing light, and the diffuse scattered light, which suffers multiple scattering, becomes a global interference. Therefore, we can write the following:  
\[I_{view}=I_{bal}+I_{sna}+I_{sca}=I_{obj}T+I_{sna}+I_{lllu}(1-T) \tag{1}\]  
where \(I_{view}\) is the viewed light, \(I_{bal}\) is the ballistic light, \(I_{sna}\) is the snake light, \(I_{sca}\) is the diffuse scattered light, and \(I_{obj}\) is the directly reflected light from the object. The ballistic light follows geometric optics and suffers degradation by the Lambert-Beer law as \(T=\exp(-\beta_{ext}L)\), where the atmospheric extinction coefficient \(\beta_{ext}\) is a constant over space and time, and \(L\) is the physical distance of the light propagation. It can be seen from Equation (1) that the ballistic light has a weak amplitude, while the scattered light has a strong amplitude, resulting in the signal with a property of low contrast. Meanwhile, the snake light renders the signal a low signal-to-noise ratio.
# Design of a Novel RFID Reader for Oilwell Downhole Applications
## 2 Design of Downhole HDX Reader Hardware
### Software Design of HDX Reader  
Considering that the electronic tags used for downhole communication have low requirements for storage space and control instructions, the electronic tag used in this design is RI-TRP-WR3P, produced by Texas Instruments Incorporated. RI-TRP-WR3P is a read-write electronic tag based on a semi-duplex communication protocol, with a length of approximately 23 mm and a weight of approximately 10 g. The operating temperature for read operations is \(-40\)\({}^{\circ}\)C to 85\({}^{\circ}\)C, and that for write operations is \(-40\)\({}^{\circ}\)C to 70\({}^{\circ}\)C. Charging for read-write operations requires a minimum of 15 ms, with a charging frequency of 134.2 kHz. During data read-write operations, RI-TRP-WR3P adopts FSK modulation to encode the signal, with a low-level frequency of 132.2 kHz to 136.2 kHz and a high-level frequency of 120.0 kHz to 128.0 kHz. Each level lasts for 16 radio frequency cycles, with a high-level time of approximately 120 us and a low-level time of approximately 128 us.  
As the data encoding type returned by the RI-TRP-WR3P electronic tag is a non-return-to-zero code, a high level represents 1 and a low level represents 0, and a high level lasts for 120 us while a low level lasts for 128 us. The decoding flowchart is shown in Figure 5. In this decoding process, a variable-named temp is first set to store the time difference between two jumps, and then the temp is judged. When the data stored in the temp are approximately 8 consecutive high-level times at the beginning of the RI-TRP-WR3P electronic tag, the value of the startbit is set to 1 to start recording the data, and the first byte of the array is stored in 0 xFF. Then, it is determined whether the time is triggered by the rising edge. If the rising edge is triggered, it represents the duration of the low-level data stored in the temp. Simply subtract one low-level time from the temp and move the data one bit to the left to save the data into the array. Then change the triggering method to ensure that the data in the next temp can be saved correctly. If the falling edge is triggered, it indicates that the data stored in the temp are of high-level duration. Simply subtract the high-level time from the temp and move the data one bit to the left and perform the OR operation with 0x01 to save the high level in the array. If the data stored in the array reach 112 bits, output the array and end the data collection, and then process the data.  
Figure 4: XR2211 demodulation circuit.
# Dense Robust 3D Reconstruction and Measurement for 3D Printing Process Based on Vision
## 2 Image Acquisition and Preprocessing in 3D Printing Process  
The vision detection device designed based on CORXY-3D printing device is shown in Figure 1, where (a) is the mechanism diagram of the detection device, and (b) is the physical diagram of the image acquisition device. The camera \(P\) is placed in a circular orbit with \(O\) as the origin. There are two coordinate systems in the figure. The \(O\)-\(XYZ\) is the coordinate system of the 3D printing platform, and the geometric center of the platform is set as the origin point, that is, the center point \(O\) of the printer frame square \(A_{1}A_{2}A_{3}A_{4}\). The \(x\)-axis is parallel to edge \(A_{1}A_{2}\), and the \(y\)-axis is on the same line with the center perpendicular of edge \(A_{1}A_{2}\). \(O\)-\(X^{\prime}\)\(Y^{\prime}Z^{\prime}\) is the coordinate system of the image acquisition target. Let the origin \(O^{\prime}\) be a point on the axis of the camera lens, and the two origins \(O\) and \(O^{\prime}\) are coaxial. Let \(O^{\prime}D=R\), \(O^{\prime}P=L\), and the height from the camera to the printer platform is \(S_{1}\). Let the value of the coordinate of \(O^{\prime}\) in the coordinate system \(O\)-\(XYZ\) (\(x^{\prime}\),\(y^{\prime}\),\(z^{\prime}\)), and the perpendicular line of \(QD\) is extended through the point \(O^{\prime}\) to intersect at a point \(D\) on \(QD\). It can be obtained by Pythagorean theorem:  
\[\left(O^{\prime}P\right)^{2}=\left(O^{\prime}D\right)^{2}+\left(DP\right)^{2} \tag{1}\]and we can get the following equation:  
\[L^{2}=(R-X)^{2}+Y^{2}+(S_{1}-z^{\prime})^{2} \tag{2}\]  
According to the above formula, the camera height \(S_{1}\) can be solved as follows:  
\[S_{1}=z^{\prime}\pm\sqrt{L^{2}-\left(R-X\right)^{2}-Y^{2}} \tag{3}\]  
It can be seen from Figure 1a that the camera rotates around the Corexy printer on the ring track for image acquisition. If the camera angle is not changed during the shooting process, the height of any point on the ring is required to remain unchanged to ensure that the camera axis intersects at the same point. The designed machine vision detection system can change the field of view by adjusting the shooting angle of the camera in the vertical direction and the position of the camera in the circular orbit. The view position of the single camera in the process of motion is set to avoid the view occlusion of the detection device to the test structure, and then complete the collection of sequence images. When the image is collected, the printing platform is lowered to a certain distance so that the camera can sample the image around the 3D printed part. After the image is collected, it needs to be preprocessed, including image enhancement processing and image filtering.
# A Survey on Unmanned Surface Vehicles for Disaster Robotics: Main Challenges and Directions
## 2 Groundwork
### Survey Protocol  
In this paper, the research focus is the direct use of USVs in natural and environmental disasters. Homeland security problems, environmental monitoring tasks, and general-purpose works--e.g., water monitoring, control--are beyond the scope of this work. This work focuses on peer-reviewed papers, both conference and journal papers. Therefore, unless we deem necessary, we avoid referencing technical reports or book chapters.  
The research protocol involves an initial search using conventional research databases such as Google Scholar and IEEE Explore, using the keywords from Table 1.  
Then, we performed a snowball search approach [52] to cover references and citing work. Each work was included or excluded according to a top-down analysis of the title, abstract, and text body. General-purpose works that only mention disasters as motivation are out of scope since our focus involves USV research directly associated with disasters.  
Two major challenges of the research protocol are related to the restriction of the number of characters of search engines and the large and different expressions used as alternative nomenclature for USVs. Our approach to solving these issues was to use regular expressions and also separate the search by disaster type or application as the research evolved. Another challenge for this work is the proximity of terms involving unmanned systems and disasters, which we could not avoid.  
Figure 2: The distribution of surveys analyzed. From those associated with DM, only one is dedicated to UMVs, but none to USVs exclusively. Please note that if we remove works exclusively focusing on USVs from the list, the number of surveys drops to zero.  
For example, the term \"flood\" is also used in computer networking, which means sending a packet to every outgoing link. Concerning nomenclature, we decided to use only the term USV in the whole paper, despite possible differences from remotely operated and autonomous surface vehicles. The final challenge of the present endeavor was the fact that it involves a multidisciplinary field, where works are spread across many publications. As a workaround, we have split the problem into parts where team members addressed specific subareas, namely SAR, structure inspection, specific disasters associated with USVs, and contaminants-- i.e., radiation, chemical, and biological ones.  
From thousands of works, we narrowed the relevant papers which are presented in the remainder of this paper.
# Impact of Implant Design and Bone Properties on the Primary Stability of Orthodontic Mini-Implants
## 4 Discussion
An analysis of the values presented in Table 5 showed that the highest TSF ratio is associated with the Perfect Anchor 1.4 mm \(\times\) 8 mm mini-implant (TSF = 0.380), which is followed by the Perfect Anchor 1.6 mm \(\times\) 8 mm implant (TSF = 0.340), while the lowest TSF ratio is associated with the Tomas-pin 1.6 mm \(\times\) 6 mm implant (TSF = 0.270). The analysis of variance was used to test the impact of the mini-implant geometry on the pullout force, and proved that there was a statistically significant impact (_p_ < 0.015) of all three analyzed geometric factors on the pullout force of the implant, which is presented in Table 6.  
Our study shows that the implant with the highest average pitch value was found to have the highest average pullout force (Tomas-pin 1.6 mm \(\times\) 6 mm), while the implant with the lowest average pitch value (Perfect Anchor 1.4 mm \(\times\) 8 mm) was found to have the lowest average pullout force. Reducing the diameter of the mini-implant increases the likelihood of it loosening and cracking, and ultimately increases the risk of it falling out [23; 24]. Studies [25; 26; 27; 28; 29] have also indicated that in addition to the mini-implant design, its primary stability also depends on the bone quality and quantity at the point of its insertion. The tests conducted show that there is a significant influence of the thread core diameter and the thread core taper on the stability of the implant with the same nominal diameter (1.6 mm). Thus, a Tomas-pin with larger core diameters and a larger half angle of thread taper showed the higher values pullout forces in the pull-out test compared to the Perfect Anchor, although it had a shorter threaded section. This conclusion can be brought into connection with research undertaken as part of a study [20] performed on shorter but thicker screws compared with the screws of standard dimensions, which ultimately showed the advantage of non-standard (shorter and thicker) screws. After completing our study, we have moved a few steps closer to the view taken by a group of authors in their research [16], who indicated that the design of a mini-implant, i.e., its diameter and geometry, have a much greater impact on primary stability than the length itself.
# Optimization of Image Capture Distance for Facial Thermograms in Dentistry
## 4 Discussion
The facial surface temperature variations during the post-surgical healing phase following a dental treatment have been documented to be in the range of 2.1 \({}^{\circ}\)C and 2.8 \({}^{\circ}\)C, and therefore the camera employed was sufficient to perform the required task [59, 67]. Nevertheless, future studies are deemed necessary to compare the present findings using cameras with superior hardware.
## 2 Computational Principles and Methods  
### Calculation Parameters  
In the study, the CASTEP code is employed to perform the first principles calculations of all total energy electronic structures. Calculations were performed using norm-conserving pseudopotentials [29] with 3d\({}^{7}\)4s\({}^{2}\) electrons used as valence for Co, 4d\({}^{2}\)5s\({}^{2}\) electrons used as valence for Zr and 3s\({}^{2}\)3p\({}^{6}\)3d\({}^{2}\)4s\({}^{2}\) electrons used as valence for Ti. The exchange-correlation energy of electrons is calculated through GGA-PBE function that is the combination of the Perdew-Burke-Ernzerhof (PBE) system and generalized gradient function (GGA) [30]. It can measure precisely the relaxed lattice constants, ensuring high accuracy of calculation. In our computations, the cutoff energy of plane waves expanding the electronic wave functions that is set for Co\({}_{2}\)Zr and Co\({}_{2}\)Ti is 540 eV, 500 eV for Co\({}_{3}\)Ti [24]. Referring to the conclusion of Monkhorst-Pack [31], the k-points of Co\({}_{2}\)Zr and Co\({}_{2}\)Ti are set as \(6\times 6\times 6\) and \(7\times 7\times 7\), and \(15\times 15\times 15\) for Co\({}_{3}\)Ti [24], respectively, for Brillouin zone integration. Based on these parameters, the total energy of Co\({}_{2}\)Zr and Co\({}_{2}\)Ti is self-consistent converging to \(3.4\times 10^{-7}\) eV/atomand \(2.0\times 10^{-7}\) ev/atom. These parameters are sufficient to calculate well converged total energy, geometrical configurations and elastic stiffness coefficients.
## 5 Immersive Simulation Platform Application Case
### Application Case of Simulation Platform Based on Motion Capture  
Based on the experimental platform of the Liaoning Province Key Laboratory of Intelligent Ship Technology and Systems, a 1:48 scale ship surface model was constructed. This model incorporates an indoor camera and a motion capture system for real-time tracking, while the UDP communication protocol is utilized to exchange data with the  
Figure 11: Schematic diagram of carrier aircraft landing support transfer.  
Figure 10: Schematic diagram of takeoff and dispatch of carrier aircraft.  
simulation platform. These data include the position, speed, attitude, and other state information of the carrier aircraft on the ship's surface. Using the scaled model, the actual trajectory and scheduling process of the carrier-based aircraft can be simulated at a reduced scale, enabling more efficient and accurate simulation and analysis.  
The motion capture system utilizes multiple high-definition cameras for synchronized shooting to capture the motion data of the carrier aircraft on the model, as shown in Figure 12. By obtaining real-time dynamic information of the carrier aircraft and integrating it with the virtual ship model in the simulation system, a closed-loop control system is established. This allows the simulation platform to continuously update the real-time state of the carrier aircraft.  
In the motion simulation of landing recovery, after the successful landing of the carrier aircraft, its engine is shut down, and it must be towed to the designated support position by a tractor. The motion command data from the host computer is transmitted to the moving object within the motion capture system via UDP. The Unity 3D terminal then receives the real-time information of the moving object broadcast by the motion capture network over the LAN and instantiates the real-time display on the terminal. The physical scale model used in the experiment is shown in Figure 13.  
Figure 12: Schematic diagram of the composition of the motion capture system.  
Figure 13: Traction system comprising tractor and shipboard unit.  
By comparing (a) and (b) in Figure 14, it is evident that in the dynamic capture system, the motion attitude of the scaled carrier-based aircraft is fed back in real time and displayed on the host computer. The use of dynamic capture technology on the scaled model effectively reduces the cost and risk associated with actual carrier aircraft scheduling experiments, while enhancing the application of the simulation platform in carrier aircraft scheduling and operational tasks. The curve description in Figure 14 is the same as that in Figure 11.
# Research on Waveform Adaptability Based on Lunar Channels
## 1 Introduction
Section 4 presents numerical results on the performance of the waveforms we designed for lunar communication, including simulation parameters and results for Peak-to-Average Power Ratio (PAPR) and Bit Error Rate (BER). Section 5 summarizes our research, emphasizing the applicability of OFDMA and SC-FDMA waveforms in the lunar environment and how our designed transmission structure meets the system-level performance requirements for lunar communication.
# Magnetic Field-Based Vehicle Positioning System in Long Tunnel Environment
## 3 Proposed System Explanation
### Device Calibration
\begin{array}{l}\Phi^{\mu}=\left[\begin{array}{cc}p^{\mu,\rho}&\phi^{\mu} \\ p^{\mu,\rho}&x^{u}&y^{u}&z^{u}\\ \end{array}\right]\end{array}  \tag{2}\]  
where \(p^{\mu,\rho}\) is the user position from GNSS outdoors and \(\phi^{\mu}\) is the magnetic field value of the user smartphone. If \(p^{\mu,\rho}\) is close to \(p_{k}^{d,\rho}\), we assumed that the magnetic field value of user smartphone is identical with the magnetic fingerprint DB value as:  
\[ \begin{array}{l}\phi_{k}^{d,0}\triangleq C_{b}^{d}\cdot\phi^{\mu}+\xi\end{array}  \tag{3}\]  
where \(C_{b}^{d}\) is the rotation matrix used to transform the body frame into the DB frame. Finally, the compensation value, \(\xi\), can be obtained as:  
\[ \begin{array}{l}\xi=\phi_{k}^{d,0}-C_{b}^{d}\cdot\phi^{\mu}.\end{array}  \tag{4}\]
## 3 Results
### Analysis and Description of Data
#### 3.1.2 Aim 2
\begin{table}
\begin{tabular}{l l l l l l l l l l} \hline \hline
**Overall** & **Total** & \begin{tabular}{l} **Strongly** \\ **Disagree** \\ \end{tabular} & **Disagree** & \
\begin{tabular}{l} **Neither Disagree** \\ **Nor Agree** \\ \end{tabular} & **Agree** &
\begin{tabular}{l} **Strongly** \\ **Agree** \\ \end{tabular} & **Md.** & **M** & **Sd.** \\ \hline
**Teaching** & & & & & & & & & \\
1. AR allows teaching to happen via discovery. & & & & & & & & \\ Fr. & 106 & 3 & 3 & 8 & 29 & 63 & 5.00 & 4.38 & 0.951 \\ \% & 100 & 2.8 & 2.8 & 7.5 & 27.4 & 59.4 & & & & \\
2. AR can be another way for the teacher to teach knowledge as well as using books and note taking & & & & & & & & \\ Frq. & 106 & 1 & 0 & 9 & 31 & 65 & 5.00 & 4.50 & 0.734 \\ \% & 100 & 0.9 & 0 & 8.5 & 29.2 & 61.3 & 5.00 & 4.50 & 0.734 \\
3. Teachers can teach better if they also use AR in the classroom & & & & & & & & \\ Frq. & 106 & 3 & 5 & 11 & 48 & 39 & 4.00 & 4.08 & 0.957 \\ \% & 100 & 2.8 & 4.7 & 10.4 & 45.3 & 36.8 & & & & \\
4. AR can be used by teachers to build knowledge adapted to each area & & & & & & & & \\ Frq. & 106 & 2 & 1 & 13 & 38 & 52 & 4.00 & 4.29 & 0.862 \\ \% & 100 & 1.9 & 0.9 & 12.3 & 35.8 & 49.1 & & & & \\
**Learning** & & & & & & & & & \\
5. AR can increase students’ attention & & & & & & & & \\ Frq. & 106 & 5 & 2 & 12 & 39 & 48 & 4.00 & 4.16 & 1.025 \\ \% & 100 & 4.7 & 1.9 & 11.3 & 36.8 & 45.3 & & & & \\
6. AR can increase students’ motivation & & & & & & & & \\ Frq. & 106 & 4 & 6 & 8 & 30 & 58 & 5.00 & 4.25 & 1.067 \\ \% & 100 & 3.8 & 5.7 & 7.5 & 28.3 & 54.7 & & & & \\
7. AR helps students to understand the contents better & & & & & & & & \\ Frq. & 106 & 4 & 8 & 13 & 38 & 43 & 4.00 & 4.02 & 1.087 \\ \% & 100 & 3.8 & 7.5 & 12.3 & 35.8 & 40.6 & & & & \\
8. Activities using AR encourage students to participate more in class & & & & & & & & \\ Frq. & 106 & 6 & 6 & 12 & 43 & 39 & 4.00 & 3.97 & 1.108 \\ \% & 100 & 5.7 & 5.7 & 11.3 & 40.6 & 36.8 & & & & \\
9. AR can help students to work in collaboration & & & & & & & & \\ Frq. & 106 & 0 & 4 & 20 & 42 & 40 & 4.00 & 4.11 &.843 \\ \% & 100 & 0 & 3.8 & 18.9 & 39.6 & 37.7 & & & & \\
10. AR can improve the quality of students’ learning and studying & & & & & & & & \\ Frq. & 106 & 4 & 3 & 18 & 32 & 49 & 4.00 & 4.12 & 1.039 \\ \% & 100 & 3.8 & 2.8 & 17.0 & 30.2 & 46.2 & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Students’ overall scoring of the teaching and learning constructs. Figure 4 offers the mean scores for the items in each area. Figure 5 shows the mean values for the item that specifically measures the usefulness of AR in each area construct.
## 7 Conclusions  
The modified LFO is proposed in this paper based on a random search of Levy flight for a PV energy system. The new variable \(\beta\) is introduced to solve the global best in obtaining optimum power. The proposed algorithm has excellent performance in tracking the global maximum point under PSCs. The proposed algorithm solves three major problems, mainly intermittent tracking under non-uniform irradiances, steady-state oscillation, and stability. Simulation studies are carried out under STC, PSC, and dynamic conditions. The proposed algorithm shows excellent performance in tracking MPPT. In addition, the performance of the proposed algorithm is verified with a prototype. Both simulation and experimental results show that the proposed algorithm has zero steady-state oscillation and it is stable. The efficiency of the proposed algorithm is higher than 98%. The simulation and experimental results show that the modified LFO has successfully tracked the global maximum point for all operating conditions in which the maximum power is always extracted and fast response time is achieved.  
[PERSON] developed the simulation model, algorithm, conducted the tests, analyzed all the important findings, and wrote the manuscript; [PERSON] verified the simulation study, experimental and written manuscript; [PERSON] revised and finalized the drafted manuscript. B.I. grants the permission to conduct the experiment in Centre of Excellence for Renewable Energy and support the experimental work. All authors have read and agreed to the published version of the manuscript.  
This research work was supported by Geran Galakan Penyelidik Muda (GGPM-2020-004) from the Center for Research and Instrument Management (CRIM), Universiti Kebangsaan, Malaysia.  
Not applicable.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Characteristic**} & \multicolumn{3}{c}{**Types of MPPT Algorithm**} \\ \cline{2-4}  & **P\&O** & **PSO** & **Proposed Algorithm** \\ \hline Complexity & Simple & High & High \\ Tracking efficiency & Low & Varies & High \\ Convergence speed & Slow & High & High \\ Capability to handle partial & & & \\ shading conditions & & & \\ \hline \hline \end{tabular}
\end{table}
Table 6: Comparison between P&O, PSO, and the proposed algorithm.