esa-sceva/satcom-chunk-collection huggingface dataset:
# Long-Distance Measurements Using a Chromatic Confocal Sensor
## 2 Experimental Setup  
The chromatic confocal sensor was purposefully designed to integrate into an existing optical setup for the wave front phase measurement of 300 mm diameter optics (Figure 1), developed in [24].  
Figure 1: Phemet LabTool render.  
The experimental setup is shown in Figure 2. The sensor can be split into four main components: illuminator, collector, signal conditioner, and spectrometer. The illuminator path consists of a Tungsten-Halogen Light Source (SLS201L, Thorlabs, Newton, NJ, USA), which delivers a consistent intensity spectrum of 10 mW black-body-like radiation, spanning from 360 to 2600 nm, coupled to a multimode 50 \(\upmu\)m core optical fiber patch cable. The other end of the optical fiber is at the focal plane of a positive achromatic doublet lens of 100 mm focal length. The broadband collimated beam emerging from the collimator passes through a 50/50 non-polarizing beam splitter and finally is focused by a large singlet aspheric lens made of BK7 glass; the most relevant optical parameters are shown in Table 1. The singlet design of this lens causes a large focal shift between the extremes of the spectrum. The sample is typically placed at the midpoint of this range.  
The collector part starts when the light reflected by the sample is partially collimated by the aspheric singlet lens. Again, the singlet design of the lens produces a difference in the collimation of different wavelengths, i.e., the wavelength of the best collimation changes if the sample is moved closer or farther from the aspheric lens. The beam splitter directs the reflected light to an achromatic doublet of 30 mm focal length.  
The signal conditioner is composed of three achromatic doublets, a spatial filter, and a pinhole. The first two achromatic doublets work as a Keplerian beam expander, expanding the beam to a diameter of 25 mm in order to enable the use of a spatial filter, blocking an inner disk of 20 mm in diameter. The last achromatic doublet lens focuses the filtered light into a 200 \(\upmu\)m pinhole.  
Figure 2: Full optical setup. Shorter wavelengths will focus closer to the dispersion lens (blue), while bigger wavelengths will focus farther (red).  
The spectrometer (CCS175, Newton, NJ, Thorlabs, USA) is coupled via a bundle fiber to the back of the pinhole. The spectral range is from 500 to 1000 nm with a resolution of 0.16 nm. The full chromatic confocal sensor assembly is shown in Figure 3.  
Finally, the displacement of the sample towards the main lens results in a shift of the spectrum's maxima towards shorter wavelengths; a converse shift occurs when the sample is displaced further from the main lens.
###### Abstract  
For many applications deployed in manufacturing networks, communication latency has been a significant barrier. Despite the constant development of improved communication protocols and standards during Industry 4.0, the latency problem persists, lowering quality of services (QoS) and quality of experience (QoE). Tactile internet (TI), with its high availability, security, and ultra-low latency, will add a new dimension to human-machine interaction (HMI) by enabling haptic and tactile sensations. The tactile internet (TI) is a cutting-edge technology that uses 5G and beyond (B5G) communications to enable real-time interaction of haptic data over the internet between tactile ends. This emerging TI technology is regarded as the next evolutionary step for the Internet of Things (IoT) and is expected to bring about massive changes towards Society 5.0 and to address complex issues in current society. To that end, the 5G mobile communication systems will support the TI at the wireless edge. As a result, TI can be used as a backbone for delay mitigation in conjunction with 5G networks, allowing for ultra-reliable low latency applications like Smart Manufacturing, virtual reality, and augmented reality. Consequently, the purpose of this paper is to present the current state of 5G and TI, as well as the challenges and future trends for 5G networks beyond 2021, as well as a conceptual framework for integrating 5G and TI into existing industrial case studies, with a focus on the design aspects and layers of TI, such as the master, network, and slave layers. Finally, the key publications focused on the key enabling technologies of TI are summarized and the beyond 5G era towards Society 5.0 based on cyber-physical systems is discussed.  
t pacs: 11  
Accepted: 16 December 2021  
Published: 20 December 2021  
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# A Novel STDM Watermarking Using Visual Saliency-Based JND Model
## 5 Experimental Results and Analysis
### Experiment of Robustness with VSI = 0.982
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Attack** & **STDM-RW** & **STDM-AdpWM** & **STDM-RDMWm** & **LSTDM-WM** & **Proposed** \\ \hline Salt-and-peppers noise & & & & & \\
0.015 & 0.2129 & 0.1885 & 0.1885 & 0.1221 & 0.1145 \\ \hline Wiener filtering & & & & & \\
3 \(\times\) 3 & 0.0869 & 0.0938 & 0.0549 & 0.1064 & 0.0479 \\ \hline Median filtering & & & & & \\
3 \(\times\) 3 & 0.1143 & 0.1094 & 0.0840 & 0.1038 & 0.0645 \\ \hline Average & 0.1380 & 0.1306 & 0.1091 & 0.1107 & 0.0756 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The BER comparisons for some common attacks with VSI = 0.982. Figure 8: BER versus volumetric scaling factor for different watermarking algorithms with VSI = 0.982. Figure 7: BER versus JPEG compression for different watermarking algorithms with VSI = 0.982. Similar to the above, robustness of the above schemes is tested under some common attacks with the \(VSI=0.982\) and the results are depicted in Table 2. From the average values, we can see our scheme outperforms other schemes and has good robustness for some common attacks.
## 5 Discussion
### Accelerated Learning--The Learning Period Concerning New Vocabulary Acquired  
Our study found that acquiring vocabulary using computer-assisted language learning (CALL) with additional background cognitive and emotional stimuli led to an increase in new vocabulary in a short time frame. This was true with both 2D and VRH interfaces.  
When comparing studies of computer-assisted-language learning (CALL), which does not include accelerated learning components, our study showed that more words were learned in a short learning period. In a meta-analysis study on the impact of technology use on foreign language acquisition, it was found that technology positively impacted language learning outcomes compared to traditional learning methods [11]. It is noteworthy that previous studies did not highlight the time required for learning. Moreover, despite some vocabulary increase, it was minor in relation to the time invested [49; 55; 61; 63].  
For example, in [PERSON]'s study [55], the participants were exposed to 25 words for 35 min, and in [PERSON]'s [63] study, 30 words were learned over 12 days, with each study session lasting 45 min. In [PERSON] and [PERSON]'s study [49], 90 new words were presented during seven sessions, each lasting an hour. [PERSON]'s study [61] presented participants with 60 new words during a 25 min study session. Moreover, it was possible to repeat and memorize the same word in all of these studies without any time limitation.  
Unlike other learning systems, our study was not based on memorization or repetition. The participants were first exposed to new words in the evening and again the following morning. The learners were exposed to 550 new words in the framework of five study units, each consisting of 45 min without offering the possibility of repetition.  
Alternative explanations for the study's findings exist. Still, they do not seem to alter the conclusion that the learning acceleration system is the primary factor contributing to the learners' achievements. For example, even if participants reviewed words before the first test, they were only tested on 53 randomly selected words out of 550, making it unlikely that additional review fully accounts for their high scores. The participants conducted the test independently, but the file was locked to prevent changes, and the response time was limited. Finally, participants were unaware of a second test a month later, making it unlikely that they prepared in advance.  
It is worth noting that good results were achieved in this study in a short time frame with the assistance of background cognitive and emotional stimuli that were inserted into the learning system. These components contributed to accelerating vocabulary learning with a high level of processing and retention.
# Empowering a Broadband Communications Course with a Unified Module on 5G and Fixed 5G Networks +
###### Abstract  
Telecommunications profoundly impacts all major aspects of our everyday life. As a consequence, student instruction typically includes a series of specialized courses, each addressing a distinct telecommunication area, separating wireless from fixed (optical) communications. This creates the problem of knowledge fragmentation, hindering the student's perception of the topic since, at the service level, the applications and services offered to the users seem \"virtually\" independent from the underlying infrastructure. In this paper, to address this problem, we designed, analyzed, and implemented a 6 h course module on the five generations of wireless and fixed networks, which was presented as an integral part of the undergraduate course \"Broadband Communications\", which was offered at the Dept. of Electrical and Electronic Engineering, School of Pedagogical and Technological Education (ASPETE), Athens, Greece. The main targets of this module are the following. Firstly, it aims to familiarize students with the fixed generations taxonomy, defined by the ETSI Industry Specification Group (ISG) F5G. This taxonomy serves as a foundation for understanding the evolution of telecommunications technologies. Secondly, the module seeks to integrate the acquired knowledge of the students in their previous telecommunication-related courses. During their curriculum, this knowledge was divided into two separate parts: wireless and fixed (optical). By coupling these two areas, students can develop a deeper understanding of the field. Lastly, the module aims to explore cutting-edge technologies and advancements in the telecommunications industry. In this way, it prepares students to enter the professional world during the fifth-generation era. Additionally, it provides them with valuable insights into the ongoing research and development in the field of 6G. Overall, this module serves as a comprehensive platform for students to enhance their understanding of telecommunications, from the foundational concepts to the latest advancements. To evaluate the impact of this module, the students were asked to fill out a questionnaire that included seven questions upon module completion. This questionnaire was completed successfully by 32 students in the previous academic year and by 16 students in this academic year. Moreover, a 20-question multiple choice quiz was offered to the students, allowing us to probe more into the typical errors and misconceptions about the topic.  
6G; F5G; network evolution; broadband communications; network services; telecommunications course; educational telecommunications +
Footnote †: This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ([[https://creativecommons.org/licenses/by/4.0/](https://creativecommons.org/licenses/by/4.0/)]([https://creativecommons.org/licenses/by/4.0/](https://creativecommons.org/licenses/by/4.0/))).
###### Abstract  
This study presents Pb(II) recovery/removal from water solutions using two different commercial ion-exchange resins, i.e., Dowex G-26 with sulfonic functional group and Puromet(tm) MTS9570 with sulfonic and phosphonic functional groups. Overall, 100% Pb(II) recovery/removal by both resins was obtained at solution pH 3.5, resin dosage 25 g/L, adsorption time 30 min, room temperature, and initial Pb(II) concentration 1000 mg/L. Langmuir, Freundlich, and Temkin isotherms were used to model the experimental data. The mechanism of the adsorption process was investigated using kinetic and thermodynamic models. The experimental data fitted very well with the pseudo-second-order kinetic model, and thermodynamic analysis showed that the adsorption of Pb(II) from acidic solution onto both resins was a spontaneous and endothermic process in nature. Regeneration of the resins loaded with lead ions was tested for three cycles to evaluate the resin recyclability. Good stability of G-26 and performance degradation of MTS9570 resin was observed.  
Pb(II); ion-exchange resins; regeneration; isotherms; kinetics; thermodynamics Article
## 3 Results and Discussion
### Major Volatile Compounds and Polyols
Y: yeast effect; A: activator effect; Y \(\times\) A: interaction between yeast and activator. WY: wine obtained by spontaneous fermentation; WY + Act: wine obtained by spontaneous fermentation with activator; AGGLO: wine obtained by fermentation with Levulia\({}^{\text{(b)}}\) AGGLO; AGGLO + Act: fermentation with Levulia\({}^{\text{(b)}}\) AGGLO supplemented with an activator. isobutanol, and 3-methyl-1-butanol alcohols, while 2-phenylethanol decreased their levels, in accordance with other studies [39]. The data matrix constructed with the contents of major volatiles and polyols was subjected to a PCA, resulting in a biplot showing the distribution of the four wines obtained (Figure 2). The first two components explain 79.96% of the total variance, clustering the wines into two groups. Those from the AGGLO yeast are on the right, with higher values of PC1 than the WY wines. This indicates a clear difference in the volatile profiles associated with the different yeasts. It is worth noting that the WY + Act wines are grouped close to their counterparts not supplemented (WY), and yet important differences are obtained for AGGLO and AGGLO + Act in their PC2 values, whose separation on the biplot is higher. The wines produced by spontaneous fermentation (WY) show negative values for PC1, which is mainly influenced by compounds such as acetaldehyde and methanol, which show strong negative loadings. The WY + Act samples show some overlap with the WY samples but are slightly shifted along PC2, indicating a moderate differentiation and, consequently, a similar volatile profile based on these volatiles and polyols. The AGGLO wines have positive values for PC1, indicating that they are influenced by volatile compounds with positive loadings on PC1, such as 2,3-butanediol, 2-phenylethanol, glycerol, and acetoin. The AGGLO + Act samples are further shifted along PC2, a shift driven by 1-propanol, isoamyl alcohols, and isobutanol, which have strong positive loadings on PC2 (Table S1. Supplementary Materials).
# Modeling of Historical Marine Casualty on S-100 Electronic Navigational Charts
## 5 Discussion and Limitation
### Need for User-Centered Evaluation  
Beyond technical validation, it is crucial to assess how effectively the model supports real-world decision-making by end-users such as navigators, VTS officers, and maritime analysts. The current study focused on data modeling and system-level visualization, without direct involvement of operational users. This limits the ability to evaluate usability, relevance, and situational awareness in practical contexts.  
To address this gap, we plan to conduct a structured usability evaluation in future work, following the ISO/IEC 25023 standard [35]. Evaluation metrics will include task effectiveness (e.g., correct identification of incidents), efficiency (e.g., completion time), and user satisfaction (e.g., perceived clarity and usefulness). Scenario-based testing will be performed with professional users who interact with the casualty data in simulated navigational tasks. Their feedback will inform adjustments to both the data structure and portrayal logic, ensuring the model aligns with operational expectations and cognitive workflows.
## 4 System Model and Description of the Proposed Protocols
### Proposed Protocol 2 (BF-SPR-Three)
#### 4.2.2 Detailed Theoretical Analysis of Propagation and Data Transmission Model  
In this section, the propagation model and the EC model of the acoustic signals are explained. In addition, the absorption constraints are also formulated in the underwater environment. The propagation and EC model include:  
**Channel Fading Model in BF-SPR-Three**  
The attenuation of the acoustic channel is formulated using Equation (2) as in [24]:  
\[A(Dis,Feq)=Dis^{k}\times\alpha(Feq^{Dis}), \tag{2}\]  
where \(k\) represents the spreading factor. Whereas, \(\alpha(Feq^{Dis})\) denotes absorption coefficient. Basically, k is describing the propagation pattern. For cylindrical spreading, \(k\) is taken as 1 with limited propagation pattern (with no attenuation). Similarly, for practical spreading, the value of \(k\) is taken as 1.5. In this spreading, the signal propagation considers both transmission and attenuation losses to get the precise result. In the end, \(k\) is taken as 2 for spherical spreading. In spherical spreading, the signal propagates in omni directions. However, these waves move a long way from source by keeping the power of the signal same. The \(\alpha(Feq)\) is defined by Thorp's Model as in [24].  
\[\alpha(Feq)=\frac{0.11\times Feq^{2}}{1+Feq^{2}}+\frac{44\times Feq^{2}}{4100 +Feq^{2}}+2.75\times 10^{-4}\times Feq^{2}+0.003. \tag{3}\]  
Here, \(\alpha(Feq)\) is measured in dB/Km and \(f\) is measured in KHz, respectively. The relationship between \(\alpha(Feq)\) and \(Feq\) is shown in Figure 11. From the figure, it is obvious that the absorption rate of the acoustic signal increases with the increase in \(Feq\) value. IoT-UWSN includes shipping noise, thermal noise and turbulence noise. Therefore, these noises affect the acoustic channel during transmission. The total Noise Power \((NP)\) including the spectral density of all the noises at frequency \(Feq\) is calculated as [24]:  
\[NP(Feq)=\sum_{i=1}^{tn}NP_{i}(Feq), \tag{4}\]  
where, the aforemention total noises are represented by \(tn\). The value of \(NP\) is measured in dB. The attenuation over the distance \(Dis\) is calculated using Equation (5).  
Figure 10: System Model of BF-SPR-Three.  
\[NP^{Dis}(Feq)=\sum_{i=1}^{tn}\frac{NP_{i}(Feq)}{Dis^{k}\alpha(Feq^{Dis})}. \tag{5}\]  
Here, \(NP^{Dis}(Feq)\) is measured in dB and it should be lies in between (1-tn).
# Fatigue Performance Test and Numerical Analysis of Composite Girders with CSW-CFST Truss Chords
## 4 Non-Linear Numerical Analysis
### Non-Linear Numerical Analysis Model
The hot-spot stress at XL3 under different mesh sizes is shown in Figure 18. With reduction in mesh size, the hot-spot stress became gradually closer to the test value, but the accuracy was improved by only 1.3% when the mesh size was reduced from 2 mm to 1 mm. Therefore, in consideration of calculation accuracy and efficiency, as well as the thickness of the welding steel plate in the test which was 4 mm, the mesh size in the vicinity of the hot-spot in the finite element model was taken to be 2 mm. The mesh size in other regions can be enlarged. The load-displacement curve and the hot-spot stress distribution obtained from the fatigue performance test and non-linear numerical analysis are compared in Figure 19. The load-displacement curve and hot-spot stress distribution obtained from the fatigue performance test and non-linear numerical analysis were consistent under the peak load. The deviations of the maximum displacement and the maximum hot-spot stress were less than 9.8% and 6.2%, respectively. Thus, it can be concluded that the overall performance of the actual composite girder with CSW-CFST truss chords was accurately reflected in the non-linear numerical model. Figure 17: Comparison of different contact methods.
# Depth Image Super Resolution Based on Edge-Guided Method
## 2 Proposed Method  
In this section, we first present the general steps of our work. Then, the way we have built the LR and HR edge dictionaries is discussed. Afterward, we continue with the details of how to interpolate HR image by joint bilateral filter.  
To keep blurred and jagged edges away from the final SR result, we present a novel depth image SR method, which employs joint bilateral filter based on edge guidance for LR-to-HR reconstruction. The general steps of the proposed depth image SR method are summarized and shown in Figure 1.  
To avoid computational complexity caused by the different size between LR image and the final HR image, we first use simple interpolation algorithm (bicubic interpolation) to magnify the input LR image \(\mathbf{I}_{l}\) to the same size as the final HR image. However, interpolation algorithm can cause blurred and jagged effects near edges, so we use a Shock filter [27] to clear the magnified image for further process.  
Edges provide essential structural information to describe the objects in the scene. Thus, we first focus to recover HR edges before reconstructing the whole image. As illustrated in Figure 1, LR edge map \(\mathbf{E}_{l}\) is extracted from the preprocessed LR image. Edge map preserves only the primary structure information and abandons widespread smooth area. This leads to it having very strong sparseness. Thus, we choose sparse coding method to recover HR edge map \(\mathbf{E}_{h}\) in our method.  
After getting HR edge map \(\mathbf{E}_{h}\), depth image \(\mathbf{I}_{h}\) will be interpolated by a modified joint bilateral filter under the guidance of the high-quality edge map. The usage of bilateral filter can not only preserve the edge sharpness but also suppress noise further.  
Figure 1: Pipeline of the edge-guided depth image SR.  
From the above introduction, the proposed method mainly includes two important parts: (1) edge recovery using sparse coding method; and (2) edge-guided depth interpolation using bilateral filter. The details on these two parts will be discussed in the following subsections.