esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Discussion
### Experimental Results
The circulating current is minimal, with lower fluctuations with the use of CVB-PQ and CVB-VSG controls (1.6 A and 1.4 A) compared to the PQ and VSG controls (3.6 A and 3.4 A), respectively. Figures 8e and 9e depict the DC current for the PQ, VSG, CVB-PQ, and CVB-VSG controls, respectively. The DC current is more stable and exhibits lower fluctuations (1 A and 0.9 A) in the CVB-PQ and CVB-VSG controls compared to the PQ and VSG controls (fluctuations of 1.6 A and 1.4 A), respectively. Figures 8f and 9f clearly show that the active and reactive powers follow the power references (ranging from 80 W to 120 W for active power and 0 VAR for reactive power) for the PQ, VSG, CVB-PQ, and CVB-VSG control strategies, respectively. A slight disturbance in active power (P = 120 W) is observed for the PQ and VSG control, whereas the CVB-PQ and CVB-VSG control exhibit greater stability. We clarify that Figures 8a and 9a show the raw oscilloscope recordings of the voltages, captured directly using a Tektronix oscilloscope, thereby illustrating the real-time measured signals during the experimental tests. In contrast, Figures 8b-f and 9b-f present post-processed experimental data: the signals were captured using a data acquisition system and subsequently processed and evaluated within MATLAB. This analysis enabled the extraction and emphasis of critical parameters (including circulating current, DC voltage,active power, reactive power, and others) while effectively removing unwanted noise to ensure the clarity and accuracy of the results. The numerical data in Table 3, obtained from practical validations, serve as a robust foundation for the evaluation and comparison of the PQ, VSG, CVB-PQ, and CVB-VSG control methods. These practical validations offer real-world insights into the performance of each method, allowing for a comprehensive analysis of their effectiveness. Based on the simulation and experimental results, SM capacitor voltage-balancing techniques like CVB provide an effective solution to enhance the stability and performance of MMC systems. The CVB-VSG control, in particular, offers several potential advantages, including simplicity, reliability, fast response, and the ability to adapt to dynamic variations. These advantages highlight the potential benefits of using CVB-VSG control for MMC systems.
# Model Test on Grouting Properties of Alluvial Filler Soil
## 7 Engineering Characteristic Analysis of Grouting Soil
### Geological Radar Scanning
#### 7.1.3 Test Results Analysis  
The comparative analysis of the geological radar imaging before and after grouting of lines 1, 4, and 7 was as follows:  
(1) The Geo-radar scanning images before and after grouting line 1 are shown in Figure 9. The analysis shows that the soil is loose in the right 0.8-1.6 m depth range before grouting. The waveform is strongly reflected at the depth of 1.4 m, indicating the existence of a distinct interface, which may be the cause of the layer compaction or the higher water content of the soil layer. While the soil on the right 0.8-1.6 m becomes denser after grouting, the strong reflection in the deep 1.4 m is not seen. It indicates that the compactness of the soil has increased and that the uniformity has obviously improved. Therefore, it can be concluded that the grouting effect in this area is very significant. After grouting, the image of depth 1.6 m below has similar signal interference, which is caused by the improvement of dielectric uniformity, the decrease of signal reflection intensity, and the decrease of depth of penetration.  
(2) The Geo-radar scanning images before and after grouting line 4 are shown in Figure 10. The analysis shows that there is little change in the continuity and dispersion of the image before and after grouting in the range of depth 0.8-1.4 m, which indicates that the effect of soil grouting reinforcement is not obvious in this range. However, under the depth of 1.4 m, the reflection intensity of the radar detection signal decreases significantly, and the detectable depth decreases, which indicates that the grouting effect is good.  
(3) The Geo-radar scanning images before and after grouting line 7 are shown in Figure 11. The analysis shows that in the range of depth 0.6-1.4 m, the radar signal is strongly reflected before the grouting, and the signal is in a diffraction arc with the phase axis, which indicates that the soil layer is not dense. The reflection signal becomes weaker after grouting, which indicates that the compactness of the soil layer is obviously improved and the effect of grouting reinforcement is obvious.  
Figure 9: The Geo-radar scanning images before and after grouting of line 1.  
To sum up, the geological radar detection shows that the grouting reinforcement effect is obvious in the grouting model test.
## 1 Introduction
### Research Questions  
To guide and narrow the SLR, a set of research questions pertaining to the application of ML algorithms in transformer fault classifications based on the DGA results are presented. These research questions are developed using the Population, Intervention, Comparison, and Outcome (PICO) framework to help ensure that a structured approach is used for a thorough search and analysis of the existing literature. Applying the PICO framework to this study, different types of transformer faults from different regions over a set period are studied, different DGA-based fault interpretation methods are explored, a comparison of the fault interpretation methods is studied, and the performance accuracy and shortcomings of the interpretation methods are analyzed. In addition to the research questions, search keywords and inclusion and exclusion criteria were also applied to narrow the search and obtain more detailed search results. The research questions are as follows:  
* What are the primary objectives and research aims that current research addresses on DGA-based transformer fault classification?
* Which research repositories and publication types are commonly used to study DGA-based transformer fault classification?
* Which global countries and regions are at the forefront of DGA-based transformer fault classification research?
* How has the research in the area of ML application in interpreting transformer faults using DGA evolved over the period 2014-2024?
* Which machine learning techniques are employed to investigate DGA-based transformer faults?
* Which software and engineering tools are frequently used to compute and analyze the DGA data?
* Which methods and industrial specifications are utilized for DGA data collection, analysis, and interpretation of the results?
* Which DGA gas components are analyzed?
* What shortcomings and limitations are identified in the literature relating to DGA-based transformer fault classification?
* What are the sources of DGA datasets used in the literature?
# Research of Enzyme-Induced Carbonate Precipitation on Strength Behavior of Reinforced Sand
## 3 Results and Discussion
### Unconfined Compressive Strength
#### 3.1.2 Influence of Relative Density on Strength  
Figure 5 demonstrates the variations in UCS of EICP-reinforced sand as influenced by relative density (\(D_{\rm r}\)) and cementation solution concentration (C) after a curing time of 7 days. The results in Figure 5 show two distinct patterns in the strength of the samples as \(D_{\rm r}\) increases, depending on the cementation solution concentration. At 0.5 mol/L, strength increases steadily with \(D_{\rm r}\). However, at higher concentrations (1.0-2.0 mol/L), strength initially rises with \(D_{\rm r}\), peaks at \(D_{\rm r}\) = 0.7, and then sharply decreases. Due to the generally lower strength at 0.5 mol/L, the optimal relative density, \(D_{\rm r}\) = 0.7, was selected for further analysis.  
This behavior can be explained as follows: at 0.5 mol/L, the low concentration of urea and calcium ions limits the formation of calcium carbonate crystals, resulting in insufficient reinforcement and lower strength. In this case, soil friction, governed by the sand's void ratio, is the primary factor influencing strength, leading to a steady increase as \(D_{\rm r}\) increases. In contrast, higher concentrations promote more calcium carbonate precipitation, enhancing cementation and surface friction between soil particles. As \(D_{\rm r}\) increases, however, the reduced void space limits the EICP solution volume, decreasing CaCO\({}_{3}\) precipitation and lowering strength. Thus, the strength of EICP-reinforced sand is a combination of the plain soil strength and the reinforcement effect, with the optimal outcome occurring at \(D_{\rm r}\) = 0.7, where both factors are balanced.
###### Abstract  
Photocatalytic membranes possessing both photocatalytic and solid-liquid separation capabilities were developed. These materials are based on ternary 1% CuO/TiO\({}_{2}\)@GCN (1:9) embedded on cellulose acetate (CA) via the phase inversion method. The CA membranes containing 0.1, 0.3 and 0.5 wt% of 1% CuO/TiO\({}_{2}\)@GCN (1:9) (CTG-100, CTG-300 and CTG-500) were fabricated. The deposition of 1% CuO/TiO\({}_{2}\)@GCN (1:9) onto the CA membranes and the consequential changes in the materials' properties were investigated with various characterization techniques. For instance, PXRD, FTIR, and XPS analysis provided evidence that photocatalytic membranes were formed. Electron microscopy and EDX were then used to visualize the photocatalytic membranes and show that the photocatalyst (1% CuO/TiO\({}_{2}\)@GCN (1:9)) was well dispersed onto the CA membrane. On the other hand, the properties of the photocatalytic membranes were scrutinized, where it was found that the membranes had a sponge-like morphology and that was significantly less hydrophilic compared to neat CA. The removal of KP in water using CTG-500 exhibited over 94% efficiency, while 38% for neat CA was achieved. Water permeability flux improved with increasing 1% CuO/TiO\({}_{2}\)@GCN (1:9) and hydrophilicity of the membranes. The electrical energy consumption was calculated and determined to be significantly lower than that of the CA membrane. The CTG-500 membrane after every cycle showed self-cleaning ability after operation in drinking and groundwater.  
Keywords:photocatalytic membrane; filtration; degradation; ground and drinking water; electrical energy consumption +
Footnote †: journal: Applied sciences
# Magnetic Nanoparticles: Synthesis, Characterization, and Their Use in Biomedical Field
## 3 NP Properties and Characterization Methods
### Chemical Properties and Their Characterization of MNPs
#### 3.2.4 Raman Spectroscopy (RS)  
RS represents a powerful set of methods that can be used to evaluate the structural and chemical properties of MNPs. The techniques are based on the inelastic scattering of the light that interacts with the sample due to molecular vibrations. Therefore, the resulting spectrum relies on the peaks corresponding to the vibrational modes of the MNPs. Modifications in peak positions or intensities, or the occurrence of new peaks, may provide valuable insights into the chemical composition, crystallinity, and structure [107; 108; 109].
## 2 Model Statement
### Doubly-Fed Induction Generator Model  
In the OWC system under study, the Wells turbine drives a Doubly Fed Induction Generator to deliver electrical power to the grid. In a \(dq\) diphase frame, the DFIG generator can be defined with the expression (11)-(16) given in [36,37]. Thus, the voltages of the stator and rotor in the \(dq\) frame can be defined as:  
\[\left\{\begin{array}{l}v_{ds}=R_{s}i_{ds}+\dfrac{d\psi_{ds}}{dt}-\omega_{s} \psi_{qs}\\ v_{qs}=R_{s}i_{qs}+\dfrac{d\psi_{qs}}{dt}+\omega_{s}\psi_{ds}\\ \end{array}\right. \tag{11}\]  
\[\left\{\begin{array}{l}v_{dr}=R_{r}i_{dr}+\dfrac{d\psi_{dr}}{dt}-\omega_{r} \psi_{qr}\\ v_{qr}=R_{r}i_{qr}+\dfrac{d\psi_{qr}}{dt}+\omega_{r}\psi_{dr}\\ \end{array}\right. \tag{12}\]  
where \(R_{s}\) and \(R_{r}\) represent the stator and rotor resistances, \(\omega_{s}\) and \(\omega_{r}\) represent the stator and rotor angular velocity, and \(i_{ds}\), \(i_{qs}\)\(i_{dr}\) and \(i_{qr}\) represent the \(d\)-\(q\) stator and rotor currents.  
The flux linkage at the stator and the rotor can be described by:  
\[\left\{\begin{array}{l}\psi_{ds}=L_{ss}i_{ds}+L_{m}i_{dr}\\ \psi_{qs}=L_{ss}i_{qs}+L_{m}i_{qr}\\ \end{array}\right. \tag{13}\]  
\[\left\{\begin{array}{l}\psi_{dr}=L_{rr}i_{dr}+L_{m}i_{ds}\\ \psi_{qr}=L_{rr}i_{qr}+L_{m}i_{qs}\\ \end{array}\right. \tag{14}\]  
where \(L_{ss}\), \(L_{rr}\) and \(L_{m}\) represent the stator, rotor and magnetizing inductances, respectively.  
The generated electromagnetic torque and its interaction with the turbine may be expressed as:  
\[T_{e}=\dfrac{3}{2}p\left(\psi_{ds}i_{qs}-\psi_{qs}i_{ds}\right) \tag{15}\]  
\[\dfrac{\int}{p}\dfrac{d\omega_{r}}{dt}=T_{e}-T_{t} \tag{16}\]  
where \(p\) represents the pair pole number and \(J\) represents the inertia of the system.  
Figure 3: Wells turbine’s characteristic curves. (**a**) Power coefficient against flow coefficient. (**b**) Torque coefficient against flow
## 4 Discussion
### Measurement Uncertainty  
One important aspect for future regulations is the uncertainty topic. At the moment, the uncertainty for PEMS analyzers is based on a simple (single point--worst case) model. Assuming a 2 ppm accuracy (including interferences), a 2.5 mg/km uncertainty is calculated for a 3 L engine for the analyzer [107] (see also Table 2). Combining the uncertainty of the exhaust flow, the distance, the trip dynamics, this value could be doubled. This value can be 5 times higher for heavy-duty engines. The values are half of the proposed future NH\({}_{3}\) limits [103]. This means that the accuracy requirement instead of \"\(\pm\)3% of the reading or \(\pm\)2 ppm, whichever is larger\", should change, for example, to \"\(\pm\)2% of the reading for concentrations \(>\) 50 ppm, and \(\pm\)1 ppm for lower concentrations\". This change would significantly reduce the uncertainty if mass limits are set (and not concentration in ppm). CEN/TS 17337, applicable to stationary sources emissions provides a detailed analysis [191]. A big step was the publication of CEN PEMS performance standard, where a second by second calculation is provided for the calculation of the final uncertainty [190]. Related to the uncertainty is also the traceability topic. The regulated gases have reached high levels of accuracy and traceability. However, this is not the case for non-regulated gases. For example, formaldehyde is tricky to calibrate because it tends to polymerize against the cylinder walls of the gas container. An old study found transfer efficiency of formaldehyde of 95.5% (\(\pm\)13.5%) for all vehicle types (gasoline, diesel, methanol) [24]. At the time of writing, the uncertainty of the formaldehyde calibration gas is much higher than the 2% uncertainty of the regulated gases. In another study, acetaldehyde standard (25 ppm in N\({}_{2}\)) could not be used because an impurity was detected in the gas bottle [168].
## 3 Seismic Control Effectiveness of the TID for Base-Isolated Structures
### Displacement Response
Figure 11: Mean squared displacement responses for each storey of the three base-isolated structures with and without different mass ratio TIDs under the three types of ground motion excitation. Next, the displacement reduction rate of the base storey is used as an index to quantify the control effectiveness of the TID. The bar charts in Figure 13a represent the percentage reduction of the mean squared displacement responses of the base storey. For the five-storey base-isolated structure, the control effectiveness of the TID is excellent. When the mass ratio is 0.2, the displacement reduction rates are 31.0%, 26.7%, and 18.6%, respectively, corresponding to the far-fault, near-fault without pulse subset, and near-fault with pulse subset ground motions. However, for the 10-storey and 15-storey base-isolated structures, the control effectiveness of the TID on the structural displacement is less ideal for the 10-storey base-isolated structures. Figure 12: Peak displacement responses for each storey of the three base-isolated structures with and without different mass ratio TIDs under the three types of ground motion excitation. near-fault ground motion excitation. The peak displacement of the isolated storey is often related to the stroke of the equipment and design requirements for isolation measures, etc. The percentage reduction of the peak displacement response of the base storey is presented in Figure 12(b). It is obvious that the control law for the peak displacement of the TID is similar to that for the mean square displacement, but the reduction rate is smaller and there are significant differences in individual conditions. For example, the control effectiveness of the TID for the 10-story isolated structure under near-fault with pulse subset ground motion is almost negligible.
## 3 Development History of Navigation Signal Authentication Technology
### Authentication Mechanism  
The authentication mechanism design includes navigation message authentication and navigation spreading code authentication.  
(1) Navigation message authentication.  
The design of navigation message authentication needs to have the following characteristics: firstly, the authentication message is compatible with the existing message format of BDS and its augmentation system. Secondly, the authentication message can meet the characteristics of a one-way broadcast of Beidou navigation signals and low message bandwidth. Thirdly, Chinese cryptographic standards should be selected as the priority for being independent and controllable.  
* BDS  
The standard positioning service of BDS includes B1C and B2a. Taking BDS B1C as an example [73; 74], the authentication message bits are reserved in advance for Galileo E1, and B1C needs to design a new authentication message frame--subframe 3 adds page 5. The B1C message frame broadcast period is 18 s, and the authentication period is 90 s, which is much longer than the Galileo authentication period (10 to 30 s). The Beidou constellation adopts the cross-authentication method and the authentication message frame offsets the transmission mechanism, which is expected to increase the authentication period to 18 s. The cross-authentication method is that Beidou satellites not only provide their own authentication information, but they also provide the authentication information of adjacent satellites. The authentication message frame offset transmission mechanism refers to the time-sharing broadcast of each satellite message authentication frame (subframe 3, page 5); that is, each satellite broadcasts a different message frame at the same time, which is different from the existing Beidou satellite broadcast strategy. There are huge challenges from the perspective of project implementation. The details of the authentication message offset transmission are as follows in Figure 12.  
Figure 11: Three-level scheme based on the TESLA protocol [72].  
* BDSBAS  
BDSBAS message authentication needs to meet the relevant documents of the International Civil Aviation Organization (ICAO) [52]. At present, it has been designated as a TESLA authentication scheme internationally, and it plans to provide authentication services at the SBAS L1 and L5 frequency in the future [54, 55]. The addition of the SBAS authentication design is limited by the constraints imposed by SARPs on the authentication system. The SBAS message format is shown in Figure 13.  
(2) Spreading Code Authentication.  
The spreading code authentication is constructed by adding an unpredictable spreading code to the spreading code sequence. Figure 3 is a GPS CHIMERA authentication spreading code design [24], and the Beidou navigation spreading code authentication design needs to have the following requirements: First, it can be compatible with the existing Beidou signal structure and will not affect the existing signal processing. Second, it is designed to take into account both fast channel authentication and slow channel authentication.
## 2 Methods  
The main electronic databases (PubMed, Web of Science, and Scopus) were explored by all the authors (C.C., B.L., and M.S.). This research was conducted from June 2024 to December 2024, and the keywords used were ((\"femoral neck fractures in elderly\" OR \"proximal femoral fractures in elderly\") AND (\"dual mobility cup arthroplasty\" OR \"hemiarthroplasty \")) NOT (osteoarthritis). MesSH terms were included. The study had no temporal limitation regarding the time of publication. A total of n = 194 articles were found. The PRISMA flowchart is shown in Figure 1. Studies providing any level of evidence about femoral neck fractures in the elderly were considered eligible for this study. The most recent and relevant studies on the topic were included, excluding duplicates, those not in English, and studies not closely related to the topic. Therefore, 48 studies were included in the final analysis (Table 1). Figure 1: The PRISMA flowchart for the selection and screening of the articles. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Author and** & **Title** & **Type of Study** & **N\({}^{\circ}\) of** & **HA/THA/DM-THA/HA vs.** & & & **Follow-Up** \\
**Year** & **Title** & **Type of Study** & **Patients** & **DM-THA/HA vs. THA/HA vs. THA vs. THA vs. THA vs. DM THA & & **OUTCOMES** & **Follow-Up** \\ \hline [PERSON] 2007 [11] & [Bipolar hip hemiarthroplasty] & Case series & 79 & HA & & DM-THA offers less stress and strain on patients compared to THA. It provides greater stability and a lower risk of acetabular protrusion than THA. & 36 \\ \hline [PERSON] 2019 [12] & Hemiarthroplasty or total hip arthroplasty in recent femoral neck fractures? & Review & HA vs. DM-THA & HA is recommended for patients who had limitations in physical activity, self-sufficiency, and walking ability prior to the fracture. & \\ \hline [PERSON] 2023 [13] & Complications of Hip & & & Common complications associated with HA treatment include dislocation, periphysette fractures, acetabular erosion, and leg-length discrepancy. Less frequent complications are neurovascular injury and capsular & \\ \hline [PERSON] 2020 [14] & Factors affecting dislocation after bipolar hemiarthroplasty in patients with femoral fracture & Retrospective case-control study & 208 & HA & Factors influencing dislocation in HA include pelvic morphological features and surgical factors. & 30.8 (12–48) \\ \hline [PERSON] 2021 [15] & Risk factors for dislocation after bipolar hemiarthroplasty. a retrospective case-control study & Retrospective case-control study & 39 & HA & All patients underwent pelvic computed tomography. Dementia and an insufficient posterior wall angle are associated with an increased risk of dislocation in HA. & 2 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Summary of selected studies.