esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Discussion
### Contribution of Polymer Entanglement to A\(\beta\) Accumulation  
We addressed the topological features of membranes, such as the entanglement of polymers. Polymer-peptide (A\(\beta\)) (i) or polymer-polymer entanglement (ii) may be considered as crucial factors affecting the A\(\beta\) accumulation on the membranes. For example, poly(ethylene oxide) (_Mw_ = 5,000,000) entangles enough to contribute to protein partitioning [34]. In this section, the effect of entanglement due to the polymer is discussed.  
PLLA-5k and PLLA-10k are good examples of case (i). The _Mw_ of both polymers is comparable to that of A\(\beta\) (approximately 4300). The other polymers used here had a higher _Mw_ than A\(\beta\). Importantly, only PLLA-5k and PLLA-10k exhibited the recovery of the _Af_ value (Figure 4B). It may be assumed that these membranes were partly disrupted by A\(\beta\), possibly due to polymer-peptide entanglement. Entanglement of A\(\beta\) with polymers bearing _Mw_ near A\(\beta\) might be entropy-driven.  
An increase in the length of the polymer backbone significantly increases the possibility of polymer-polymer entanglement (case (ii)). The _Mw_ dependency of the nucleation rate (Figure 5C) provides an interpretation with respect to the effect of the entanglement of the polymer. Condensed-fluid membranes of lipids behave similarly to linear-flexible polymers [51]. This is because the lipid molecules move on the solid support solely via lateral diffusion. A study concerning lateral diffusion of DOPC reported that the process was controlled by the entanglement between acyl chains of lipids [55]. Even in the case of DOPC, the nucleation rate was comparable to that of membranes with low _Mw_. Meanwhile, PEG-PE exhibited a low nucleation rate. Previously, [PERSON] et al. [56] suggested PEG chain-chain entanglement due to van der Waals forces as well as inter- and intra-chain hydrogen bonds that act in the PEG chains. Thus, PEG chains might interfere with the association of accumulated A\(\beta\) on membranes, possibly due to their entanglement. In addition, the surface roughness originating from the PEG chains would act as an obstacle for the association of A\(\beta\), because a rough surface made of polystyrene reportedly decelerated the two-dimensional diffusion of A\(\beta\) with 42 residues and retarded the fibrillation [33]. In contrast to PEG-PE, polymers with high _Mw_, such as iso-PMMA (_Mw_ = 5.0 \(\times\) 10\({}^{5}\)), syn-PMMA (_Mw_ = 4.0 \(\times\) 10\({}^{5}\)), and PVP (_Mw_ = 1.2 \(\times\) 10\({}^{6}\)), also easily entangle in solution, because polymers with large molecular weights generally favor their entanglement, as summarized by [PERSON] [41]. A possible entanglement of _Mw_/_M\({}_{\rm e}\) is considerably high, as shown in Table 1. These polymers reduced the accumulation of A\(\beta\) and its nucleation rate in this order.
# A Heterogeneous Robotic Swarm for Long-Term Monitoring of Marine Environments
## 4 Agent Capabilities
### Depth Control  
In order to take various measurements at different depths, there is a need for the aMussel to be capable of holding a set depth for a certain amount of time. For this reason, a method for controlling the aMussel depth based on readings from the pressure sensor was implemented. Pressure \(p\) on an object at depth \(d_{am}\) in a fluid with density \(\rho\) is defined with the following well-known formula:  
\[p=p_{atm}+\rho gd_{am} \tag{5}\]where \(p_{atm}\) is atmospheric pressure and \(g\) is the gravitational constant. The water density \(\rho\) depends on different factors including temperature and salinity which can be seen in Figure 14, but since its value in normal conditions will be around 1000 kg/m\({}^{3}\), we have assumed that 1 mbar corresponds to 1 cm of depth.  
The aMussel buoyancy system has been modelled as a triple integrator:  
\[\mathbf{x}^{\prime}=\begin{bmatrix}x_{1}^{\prime}\\ x_{2}^{\prime}\\ x_{3}^{\prime}\end{bmatrix}=\begin{bmatrix}0&1&0\\ 0&0&1\\ 0&0&0\end{bmatrix}\cdot\begin{bmatrix}x_{1}\\ x_{2}\\ x_{3}\end{bmatrix}+\begin{bmatrix}0&0&k\end{bmatrix}^{T}\cdot u, \tag{6}\]  
where \(x_{1}\) is depth \(d_{aM}\), \(x_{2}\) is velocity \(d_{aM}^{\prime}\), \(x_{3}\) is acceleration \(d_{aM}^{\prime\prime}\), \(u\) is motor PWM reference and \(k\) is a constant. To control the system, a state feedback controller designed using Ackermann's pole placement formula is used. aMussel depth control responses are shown in Figure 15, where it can be seen that the aMussel is capable of controlling its depth with the accuracy of a few centimetres, which is more than accurate enough for most applications. Further details about aMussel buoyancy modelling and depth control are given in [20].
## 3 Experiments and Analysis
### Results and Analysis
#### 3.3.2 Fruit Tracking Performance  
The proposed citrus tracking and counting algorithm based on YOLOv7-tiny and DeepSORT conducts tracking experiments on citrus videos in the dataset and obtains good tracking results. In the dynamic tracking experiments of citrus videos, fruits are obscured by multiple leaves, resulting in the intermittent detection of fruits, which produces intermittent appearance of detection frames, fragmentation identification, misidentification or identity ID jumps; meanwhile, camera motion-induced motion blur can cause prediction frame matching failures, which significantly affect tracking results. Therefore, we propose a two-stage life filter to improve the success rate of prediction frame matching, reduce fruit leakage, and mitigate identity ID jumping.  
During the dynamic tracking of citrus, complex citrus growing environments make multiple conditions, which affect the accuracy of dynamic citrus tracking counting. Those conditions are shown in Table 2. Normal conditions can be easily detected and tracked; fruit overlap identifies two or more citrus as one, resulting in a reduced value counting; fruit obscured by trunk is difficult to be detected and always makes the detection jump; motion blur makes it difficult to detect citrus and result in reduced counts; fruit obscured by branches and leaves makes detection more difficult, which counts a citrus as more than one; fragmentary images result in reduced counts. For those problems arising from obscurity in complex environments, the two stages life filter proposed in this paper effectively improves it. The method reduces the leakage rate and improves the counting accuracy through the re-matching of new trajectories.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**NO** & **Legend (of a Map, etc.)** & **Condition** & **Influence** \\ \hline \hline
1 & & \\ \hline
2 & & \\ \hline
3 & & \\ \hline \hline \end{tabular}
\end{table}
Table 2: Multiple conditions of citrus in orchard environment.  
Ten citrus videos (300-548 frames) were tracked and counted using the pre- and post-improvement tracking and counting algorithms, respectively, and the resulting tracking metrics are shown in Table 3. The MOTA of the improved algorithm is 67.14%, which is 21.78 percentage points higher than that of the pre-improved one. The MOTP is 17.88 percentage points higher, and the tracking credibility has been greatly improved. The high complexity of the citrus orchard environment and the precision of video shooting cause the identity ID of the citrus to jump very easily, which is the main reason for the tracking error. The algorithm improved by adding the two stages life filter reduces the IDSR in the detection result video from 25.97% to 15.63%, which reduces the fruit tracking error to a certain extent.
## 2 Related Work
### NeRF-Based LiDAR-Visual Fusion  
Several NeRF-SLAM systems have begun to explore the integration of visual and LiDAR data to enhance the quality of 3D scene reconstruction. For instance, NeRF-LOAM [13] introduces a neural Signed Distance Function (SDF) to classify LiDAR point clouds into ground and non-ground points, effectively reducing Z-axis drift. It also simultaneously optimizes odometry and voxel embeddings to generate dense and smooth environmental mesh maps, addressing the limitations of traditional methods in large-scale scenes. LONER [14] employs LiDAR data to train a Multi-Layer Perceptron (MLP) for estimating dense maps and sensor trajectories. By incorporating a novel information-theoretic loss function, it optimizes the online training process to achieve faster convergence and higher geometric reconstruction accuracy than other deep-supervised neural implicit frameworks. However, it still faces challenges in dynamic object removal and void filling. PIN-SLAM [15] leverages an implicit neural network representation of elastic point clouds to construct globally consistent large-scale maps without relying on GPS, Inertial Measurement Units (IMUs), or wheel odometry. Using approximately 20,000 LiDAR scans, it improves map accuracy and consistency; however, its reconstruction quality is constrained by the fixed resolution of the neural points. CLONeR [16] is an occupancy-grid-assisted neural representation that integrates camera and LiDAR data by decoupling the learning of occupancy information and color representation. By using separate MLPs for training with LiDAR and camera data, CLONeR enhances NeRF's performance in large-scale unbounded outdoor scenes, especially in sparse-view settings.
## 4 Results and Discussion
### Cavitation Characteristics  
#### 4.2.1 The Effect of Inducer  
Figures 16 and 17 show the numerical cavitation performance of the centrifugal pump with and without the inducer. Installing an inducer ahead of the main impeller significantly reduces the prototype's critical and breakdown cavitation numbers. After installing the inducer, the critical cavitation number decreased from 0.783 to 0.566, and the breakdown cavitation number decreased from 0.718 to 0.372. After reaching the critical cavitation number, the total pressure difference (pump head) without the inducer exhibits a steeper decline curve. It indicates a rapid deterioration of the pump's hydraulic performance with decreasing inlet pressure.  
Figure 14: Effect of the eccentricity of radial bearings on the radial capacity for different rotating speeds.  
Figure 15: (a) Thrust bearings' capacity and (b) axial force under different flow rates.  
Figure 18 shows the variation of the bubble volume fraction and temperature in the impeller for the cases with or without an inducer under the inlet cavitation number of 0.705. Figure 16 shows that when \(\sigma\) equals 0.705, which exceeds the critical cavitation number of the pump with an inducer, the bubble volume fraction of refrigerant is approximated as zero in the impeller. When the cavitation number is lower than the breakdown cavitation number of the pump without an inducer, the cavitation cloud develops from the impeller's leading edge downstream and blocks the impeller passage. In this working condition, as shown in Figure 18c,d, the refrigerant temperature of the cavitation cloud near the leading edge of the impeller suction side dropped by about 3 K without installing the inducer.  
Figure 16: Cavitation performance at the designed condition.  
Figure 17: Effect of inducer under different flow rates.
## 3 Results
### Penetration by NaCl Aerosol  
The mean NaCl aerosol penetration results for the studied nonwoven composites containing zeolite and silicate materials are given in Table 4, with relative changes shown in Figure 10. Deterioration of protective and functional properties of the composite materials in relation to the reference sample is marked with negative values, while the improvement of protective and functional with positive values. On the basis of the statistical analysis performed, no significant differences were found, although absorbent materials with different textural parameters were used.  
The lowest values for penetration by NaCl aerosol were obtained for the composite containing the zeolite material Na-A, the unmodified and modified silica materials MCM-41 and MCM-41 HDTMA, and the molecular sieve SM, at 2.51, 2.59, 1.94, and 2.58%. Changes in NaCl aerosol penetration for those composite variants relative to the reference sample amoun  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**No.**} & \multirow{2}{*}{**Variant**} & **Mean NaCl Aerosol** & **Standard** & \multirow{2}{*}{**Median**} & **MAX \%** & **MIN \%** \\  & & **Penetration, \%** & **Deviation** & & & \\ \hline
1 & PPQ + MCM-41 & 2.59 * & 0.70 & 2.34 & 3.94 & 1.89 \\
2 & PPQ + Na-A & 2.51 * & 1.18 & 2.05 & 4.40 & 1.32 \\
3 & PPQ + Na-P1 & 4.27 * & 1.52 & 5.12 & 6.08 & 2.01 \\
4 & PPQ + SM & 2.91 * & 1.12 & 2.49 & 5.40 & 2.17 \\
5 & PPQ + SM & 2.58 * & 0.34 & 2.47 & 3.31 & 2.26 \\
6 & PPQ + MCM-4 HDTMA & 1.94 * & 0.36 & 1.95 & 2.49 & 1.45 \\
7 & PPQ + Na-A HDTMA & 16.25 * & 7.96 & 18.30 & 24.65 & 3.74 \\
8 & PPQ + Na-P1 HDTMA & 3.33* & 1.62 & 2.62 & 6.92 & 2.29 \\
9 & Pure PPQ reference sample & 2.47 & 0.26 & 2.36 & 2.93 & 2.21 \\ \hline \hline \end{tabular}  
*a–statistically significant differences were found for the mean values marked with different letters (ANOVA, \(\alpha\) = 0.05; Tukey’s test, \(\alpha\) = 0.05).  
\end{table}
Table 4: Mean NaCl aerosol penetration for nonwoven composites containing zeolite and silica materials (descriptive statistics).  
Figure 10: Relative change in NaCl aerosol penetration for nonwoven zeolite and silica composite.  
and 4.08%. The introduction of mineral additives in the structure of elementary fibers in the melt-blown process improved filtration efficiency as compared to the reference nonwoven only in one case, that is, PPQ + MCM-41 HDTMA.  
The highest NaCl penetration was found for the nonwoven composite containing the modified zeolite Na-A HDTMA, at 16.25%, with the relative penetration change being 556.54%. This is attributable to the fact that the applied zeolite contains chemical elements that may neutralize the electrostatic charges induced during the technological process.
# Development of Radio-Frequency Sensor Wake-Up with Unmanned Aerial Vehicles as an Aerial Gateway
## 6 Experimentation and Results
### Physical Verification and Comparison  
Infrared communication was directional since the wavelength was close to visible light. We used a 950 nm infrared LED as the transmitter, and TSOP38238 as the IR receiver diode. In the test, we placed the IR receiver on the ground, facing up. The UAV carried the infrared LED hovering above the receiver and continued sending signals. It was found that the effective maximum range of the IR communication was highly affected by the environmental disturbances and the variations in the supply voltage. Under strong sunlight, the IR receiver could still read signals from the LED; however, it often failed to decode the pattern in the code when the communication range exceeded 3 m by applying a 3.3 V power supply to the receiver. We found that by increasing the supply power of the IR receiver to 5 V, this issue was resolved. After multiple tests, we concluded that with our hardware setup, 5 m was a safe distance for the IR communication in an LOS space without obstruction and with a 5 V power supply for the receiver.
# A Survey on Botnets: Incentives, Evolution, Detection and Current Trends
## 4 Incentives
### Malevolent Botnets
#### 4.1.1 Designated Targets  
To understand the incentives behind the development of botnets, one must first understand the ubiquitous nature of botnets as a whole. Botnets may target a great many different objectives, sectors or groups in modern society, a natural conclusion given botnets' capacity to mobilise great numbers. The following unordered list of targets are but a handful of the potential victims and sought out results of botnets:  
* Groups of political disparity or political critics, as discussed in [PERSON]'s paper [42];
* National power grids and critical service providers, necessary infrastructure of modern day's increasingly technologically dependent societies, as described by [PERSON] et al. [54] and [PERSON] et al. [43];
* Civilian peoples' information and passwords [44; 45];
* Espionage and intelligence gathering of foreign nations [47];
* Cracking encrypted or hashed data [46].  
The difference in targets of botnets is a great incentive in the development of botnets. They can target a broad range of victims, allowing the botnet master to either target whole groups of victims, or a single institute or individual. The versatile nature of botnets caters to a extensive list of use cases, leading to an ever growing demand for powerful, subtle and specialised breed of malware for botnet-based attacks.
## 4 Sensitivity Analysis for Eigenfrequency Problems Using HYPAD  
To illustrate the new methodology for obtaining arbitrary-order sensitivities in eigenfrequency problems using HYPAD, two simple application examples are presented: one is entirely analytical and corresponds to calculating the sensitivities for a simple mass and spring system. The other application example is numerical and corresponds to obtaining the sensitivities for the case of a free vibrating cantilever beam.
# Investigating the Adsorption Behavior of Zwitterionic Surfactants on Middle Bakken Minerals
## 3 Results and Discussion
### Static Adsorption Study
#### 3.3.3 Effects of Temperature  
The impact of temperature on the interaction between 0.03% surfactant solutions and Bakken minerals was evaluated in this study. Figure 8 illustrates the adsorption at different temperatures ranging from 20 to 90 \({}^{\circ}\)C, with experimental temperatures extending from room temperature to formation temperature while other parameters were held constant. The decrease in adsorption at higher temperatures is believed to be due to the exothermic nature of the adsorption process. Previous research has also found that surfactant adsorption decreases as temperature increases [25]. This phenomenon can be attributed to the  
Figure 7: Effects of salinity.  
increased kinetic energy at higher temperatures, which weakens the interaction between surfactant solutions and adsorbents, resulting in reduced surfactant adsorption.  
Table 4 compares the findings of this study with previous research on surfactant adsorption under varying conditions. It highlights how adsorption behavior varies with surfactant type, salinity, temperature, and rock composition. The current study uniquely contributes by demonstrating that the adsorption of betaine-type zwitterionic surfactants on Bakken samples aligns with the Langmuir isotherm under high salinity and temperature conditions.
# Detection of Precipitation and Fog Using Machine Learning on Backscatter Data from Lidar Ceilometer
## 5 Concluding Remarks  
In this study, we made the first attempt to detect weather phenomena using raw backscatter data obtained from a lidar ceilometer. For weather detection, various machine-learning techniques including under-sampling and feature selection were applied to the backscatter data. The AWS provided observational data for precipitation and the visibility data from PWD20 provided observational data for fog.  
Our prediction results were not noticeably good, but if we consider the hardness of weather prediction/detection in the literature (e.g., precision and recall are about 0.5 and 0.3 for heavy rainfall prediction, respectively [13], and they are about 0.2 and 0.5 for lightning forecast, respectively [31]), our prediction results showed potential for precipitation detection (in which precision, recall, and F1 score are about 0.5, 0.2, and 0.3, respectively), but fog detection (in which precision, recall, and F1 score are all about 0.1) was found to be very difficult although it was better than random prediction.  
In future work, we expect to improve the accuracy of planetary boundary layer height (PBLH) measurements by classifying backscatter data according to precipitation occurrences.  
Conceptualization, Y.-H.K. and S.-H.M.; methodology, Y.Y. and Y.-H.K.; validation, S.-H.M. and Y.Y.; formal analysis, Y.Y.; investigation, Y.Y. and S.-H.M.; resources, Y.-H.K.; data curation, S.-H.M.; writing--original draft preparation, Y.Y.; writing--review and editing, S.-H.M.; visualization, Y.-H.K.; supervision, Y.-H.K.; project administration, Y.-H.K.; funding acquisition, Y.-H.K. All authors have read and agreed to the published version of the manuscript.  
This work was supported by the Technology Development for Supporting Weather Services, through the National Institute of Meteorological Sciences of Korea, in 2017. This research was also a part of the project titled Marine Oil Spill Risk Assessment and Development of Response Support System through Big Data Analysis', funded by the Ministry of Oceans and Fisheries, Korea.  
The authors would like to thank [PERSON] and [PERSON] for their valuable helps to greatly improve this paper.  
The authors declare that there is no conflict of interests regarding the publication of this article.
## 3 Intelligent Cluster-Based Routing Approach  
In vehicular ad hoc networks (VANETs), the intricate interplay of content placement and delivery necessitates nuanced consideration, primarily attributed to the dynamic mobility characteristic inherent to the VANET environment. Crafting a secure routing protocol for content placement and delivery is paramount in navigating this scenario. The foundational step lies in the thoughtful design of the VANET network, specifically concerning the exchange of vital information. Within the ad hoc network paradigm, three critical modes of communication come to the fore: route error (RRER), route request (RREQ), and route reply (RREP). The innovation introduced here rests upon a secure, cluster-based routing mechanism that strives for efficiency and security. Our proposed routing protocol is structured to provide precise information that promotes efficient content delivery and related placement strategies. Leveraging the mobility dynamics inherent in the system, we present an efficient cluster-based secure routing protocol meticulously tailored to minimize content request delays.
# A Novel Active Polyphase Filter Employing Frequency-Dependent Image Rejection Enhancement Technique
###### Abstract  
In low intermediate frequency (low-IF) receivers, image interference rejection is one of the core tasks to be accomplished. Conventional active polyphase filters (APPFs) are unable to have a sufficient image rejection ratio (IRR) at high operating frequencies due to the degradation of the IRR by the amplitude and phase imbalances produced by the secondary pole. The proposed solution to the above problem is a frequency-dependent image rejection enhancement technique based on secondary pole compensation. By adjusting the dominant pole frequency of the high-pass filter (HPF) appropriately, the proposed technique can theoretically completely reject the image interference signal even in the presence of the secondary pole. The proposed APPF is simulated and fabricated in a 180-nm CMOS process. The simulation results show that the proposed technique can improve the IRR of the APPF by more than 30 dB at the operating frequency of hundreds of MHz. The measured IRR is better than \(-\)31 dB at the frequency from 95 to 105 MHz. Unlike conventional schemes, the proposed design is from the perspective of frequency correlation, which makes the operating frequency no longer limited by the secondary pole frequency. In addition, the proposed design also has an excellent IRR for quadrature input signals with phase imbalance.  
Keywords:polymbase filter; complex filter; image rejection; low intermediate frequency receiver; notch filter; enhancement technique +
Footnote †: journal: _micromachines_