esa-sceva/satcom-chunk-collection huggingface dataset:
## 4 Conclusions  
In summary, we proposed a new modulation method with higher spectral efficiency and a simpler structure. Unlike traditional polarization modulation methods that require two or more modulators, by using the birefringence characteristic of LiNbO\({}_{3}\)-based MZM, the intensity modulation of both polarizations could be conducted with a single MZM. The optimal condition for the proposed method plus simulation and a proof-of-concept experiment was conducted. The polarization rate and  
Figure 8: (**a**) Experimentally measured OOK–OOK vs. theoretical OOK–OOK for given SNR relative optical power vs. BER graph. (**b**) Measured normalized intensities of the \(X\)- and \(Y\)-axes according to voltage change.  
Figure 7: 5 Gbps (2.5 GHz) OOK–OOK eye diagram: (**a**) \(X\)-axis; (**b**) \(Y\)-axis.  
voltage swing were optimized when the symbol distance per bit for each polarization was equal. The simulation result showed that as the order increased, the spectral efficiency of the proposed method also increased. This is because as the order increases, less power is required for the Y polarization. The experiment result showed that dual polarization intensity modulation is actually possible with a LiNbO\({}_{3}\)-based modulator. Despite the spectral efficiency advantages, it was checked that a higher electrical voltage swing is required for this method. Further, it was confirmed that the MZM should have a high extinction-ratio Y polarization transfer curve. However, these are experimental issues. With a feasible MZM and amplifier, we expect that the proposed technique will be useful in future high-speed optical transmission requiring a simpler structure.  
Conceptualization: Y.-J.H.; methodology, Y.-J.H.; software, Y.-J.H.; validation, Y.-J.H. and J.-Y.C.; formal analysis, Y.-J.H.; investigation, Y.-J.H.; resources, Y.-J.H.; data curation, Y.-J.H.; writing--original draft preparation; Y.-J.H.; writing--review and editing, J.-Y.C.; visualization, Y.-J.H.; supervision, S.-K.H. All authors have read and agreed to the published version of the manuscript.  
This work was supported by a grant from Institute for Information and Communications Technology Promotion (IITP), funded by the Korean government Ministry of Science and ICT (MSIT) grant no. 2019-0-00685, free-space-optical-communication-based vertical mobile network.  
Not applicable.  
The authors declare no conflict of interest.
# A Review of Hybrid VLC/RF Networks: Features, Applications, and Future Directions
## 4 VLC/RF Hybrid Network Applications
### Economic Applications  
VLC networks offer a great guarantee of security, as the transmitter and receiver must be in the line of sight, the coverage area is very small, and the transmission power is focused only on the light beam. In places where it is necessary to send and receive data that must be protected (e.g., companies, banks, hospitals) the implementation of hybrid VLC/RF networks can provide great security in data transmission [119; 127].  
In scenarios where there is a high density of users connected to the internet (e.g., stadiums, airports, and parks) the use of multiple RF access points can cause interference and reduce system performance. The use of hybrid VLC/RF networks can solve this problem by reusing the entire existing lighting infrastructure for VLC data transmission. These hybrid networks provide higher data rates, reduce RF interference, and have a very low implementation cost, making them are ideal for high user density scenarios [18; 63; 89].  
Hybrid VLC/RF networks have demonstrated a great improvement in the characteristics and capabilities of wireless communications systems. Research has focused on increasing the data rate [78; 84; 166] to improve the overall capacity of hybrid system, while other authors have focused on decreasing the system time delay [66; 81; 167].  
Mining communication systems are an application that safeguards the safety of workers in mines and increases the efficiency of their work. In recent years, VLC links have been widely investigated as a complementary technology to RF links for subway mining applications due to their high data rate and freedom from RF interference [168; 169]. Subway mines represent a challenging scenario due to their irregular walls and many shadows and dust particles, which produce the scattering phenomenon. For all of these reasons, this industry requires an optimal transverse communication system that can be supplemented by hybrid VLC/RF networks. The use of indoor, motion, and ambient dust particle sensors would be of great help in the implementation of VLC/RF networks in these and similar hostile scenarios.  
Technology is a great ally of agriculture, helping to achieve greater efficiency in farming with the objective of supplying the population without depleting the planet's resources. The implementation of hybrid VLC/RF networks in conjunction with sensors dedicated to agricultural activity can be of great help in monitoring and sending information about events concerning crops and their surroundings [170; 171].
## 3 Results
### Comparison between SIF and APAR Across Space and Time  
The \(\mathrm{SIF}_{\mathrm{inst}}\)-\(\mathrm{SIF}_{\mathrm{daily}}\) correlations changed substantially with different latitudes and weather conditions. How does this result affect the relationship between SIF and APAR or GPP? whether the SIF-APAR or SIF-GPP relationships via SIF upscaling from instantaneous to daily scales should be further verified. APAR is a bridge that links SIF to GPP [11; 13; 30] and has been proven to dominate the SIF-GPP relationship [56]. Therefore, the investigation of SIF-APAR correlations across space and time is required to better understand the SIF-GPP relationships, which is demonstrated as follows.  
Figure 8 shows the correlations between \(\mathrm{APAR}_{\mathrm{daily}}\) with the \(\mathrm{SIF}_{\mathrm{ins}}\) and upscaled \(\mathrm{SIF}_{\mathrm{daily}}\), using the two methods for sunny and cloudy days at the XTS and DM sites. Similar to the correlations shown in Figure 6, at both sites on sunny days, the \(\mathrm{R}^{2}\) values for the three kinds of SIF all exhibit weak changes, whereas, on cloudy days, the \(\mathrm{R}^{2}\) values can be greatly increased when comparing \(\mathrm{APAR}_{\mathrm{daily}}\) with PAR-based \(\mathrm{SIF}_{\mathrm{daily}}\) instead of \(\mathrm{SIF}_{\mathrm{ins}}\) or cos-based \(\mathrm{SIF}_{\mathrm{daily}}\). Figure 9 reports the correlations between \(\mathrm{SIF}_{\mathrm{ins}}\) and the upscaled \(\mathrm{SIF}_{\mathrm{daily}}\) with \(\mathrm{APAR}_{\mathrm{daily}}\) for four different latitudes simulated using observations at the XTS and DM sites. The large variations in the regression slopes for \(\mathrm{SIF}_{\mathrm{ins}}\)-\(\mathrm{APAR}_{\mathrm{daily}}\) across different latitudes could be reduced by SIF upscaling at both sites, especially when using the PAR-based method, which was also similar to the correlations shown in Figure 7.  
In conclusion, the variations in the \(\mathrm{SIF}_{\mathrm{inst}}\)-\(\mathrm{SIF}_{\mathrm{daily}}\) correlations are important reasons for the changes in the SIF-APAR relationship across space and time. At the spatial scale, the SIF-APAR relationship was impacted when using \(\mathrm{SIF}_{\mathrm{inst}}\) due to the effect of different latitudes. At the temporal scale, the SIF-APAR relationship had uncertainties when using both \(\mathrm{SIF}_{\mathrm{ins}}\) and cos-based \(\mathrm{SIF}_{\mathrm{daily}}\) due to the effect of different weather conditions. Both of these effects can be reduced and, thus, the SIF-APAR relationship across space and time can be effectively improved by upscaling \(\mathrm{SIF}_{\mathrm{inst}}\) to a daily scale using the PAR-based method.  
Figure 7: Scatter diagrams between the measured \(\mathrm{SIF}_{\mathrm{daily}}\) with \(\mathrm{SIF}_{\mathrm{inst}}\) (**a**) and the upscaled \(\mathrm{SIF}_{\mathrm{daily}}\) using the cos-based (**b**) and PAR-based (**c**) methods for the canopies of the two sites at four latitudes, as indicated by the colors. The overall coefficient of determination (\(\mathrm{R}^{2}\)) and coefficient of variation (CV) are shown in black text labels per panel.
# Stochastic Modeling for Intelligent Software-Defined Vehicular Networks: A Survey
## 4 Integrating into VANET System Model for iSDVN
### Software-Defined Internet of Vehicles  
SDIoV technology has been identified in association with different issues in this survey. The Software-Defined Internet of Vehicles (SDIoVs) is an emerging architecture that integrates SDN and the Internet of Vehicles (IoV) to enable ITSs [121; 122]. SDIoV uses SDN to provide centralized control of the IoV, which enables efficient communication, management, and coordination of vehicular networks [123]. The SDN controller in an SDIoV system can dynamically manage network resources and traffic, allowing vehicles to efficiently communicate with each other and with the infrastructure [124; 125]. This allows for the real-time coordination of traffic and intelligent routing decisions, which can improve traffic flow and reduce congestion. SDIoV also provides a platform for deploying a wide range of ITSs, such as collision avoidance, automated parking, and smart traffic lights [126]. By enabling more efficient communication and data sharing among vehicles and infrastructure, SDIoV can improve the efficiency, safety, and sustainability of transportation systems [61].  
The use of SDN in IoV environments also addresses some of the challenges associated with traditional IoV networks, such as high mobility and network scalability [127]. By centralizing network control and management, SDIoV can reduce the complexity of network management and also enable the more efficient use of network resources. However, the implementation of SDIoV also presents some challenges, such as the need for reliable wireless communication and security mechanisms to protect against cyber-attacks [53]. Additionally, the deployment of SDIoV requires a significant investment in infrastructure, including sensors, communication devices, and other network components. SDIoV is an emerging architecture that integrates SDN and IoV to enable an ITS [69]. SDIoV uses SDNto provide the centralized control of vehicular networks, enabling efficient communication, management, and traffic coordination. SDIoV can improve transportation systems' safety, efficiency, and sustainability but also presents some challenges, such as the need for reliable wireless communication and security mechanisms.
## 3 Results
### Effect of Ca\({}^{2+}\) or HA on MFRO Solute Rejection under Electric Field Conditions  
According to the data presented in Figure 7a, the solute rejection was reduced in the presence of CaCl\({}_{2}\), dropping from an initial 90.63% to 87.69% without the electric field and to 88.25% with it. This can be attributed to the different ions that accumulate on the surface of the membrane, causing an increase in the concentration polarization phenomenon and a subsequent decrease in the salt permeability rate, ultimately reducing solute rejection. However, when the electric field is applied, Ca\({}^{2+}\) migrates directionally, resulting in a relative decrease in the concentration of ions remaining near the membrane and the weakening of the concentration polarization. Consequently, the rejection of solutes is reduced.  
Figure 7b shows that the presence of HA also reduces solute rejection, from an initial value of 90.63% to 86.55% without an electric field and to 87.43% with it. The rate of decline is faster in the initial stages and tends to level off in the later stages. This can be explained by the adsorption effect of HA, which initially leads to the direct plugging of membrane pores and a reduction in permeate flux, ultimately affecting solute rejection. As the HA deposits become thicker and reach the membrane limit, the pollution tends to stabilize. However, the addition of an electric field leads to electrophoretic movement, causing HA to combine with ions in the water and leading to a slower rate of decline compared to the case without an electric field.  
Figure 7b illustrates that the presence of HA reduces the efficiency of solute rejection in RO membranes. Under normal conditions without an electric field, the solute rejection rate decreases from an initial value of 90.63% to 86.55%. When an electric field is applied, the solute rejection rate decreases to 87.43%. HA directly blocks the membrane pores, leading to a decrease in permeate flow and a subsequent effect on solute rejection, especially in the initial stages. As HA deposits accumulate and reach the membrane limit, the fouling stabilizes. However, the application of an electric field induces electrophoretic movement, causing HA to combine with ions in the water. This slows the rate at which solute rejection decreases compared to the non-electric field case, alleviating the contaminating effect of HA on the RO membrane.  
Figure 7: Effect of Ca\({}^{2+}\) or HA on the Multi-field reverse osmosis solute rejection in the absence of an electric field.
## 5 Future Perspectives  
### Technological Development Trends  
The combination of droplet jetting technology and SiC powder 3D printing is expected to achieve significant advancements in precision, printing efficiency, material and functional diversification, and automation of intelligent control in the future. These technological improvements are essential for the widespread application of SiC powder 3D-printed products in industries such as mechanical engineering, healthcare, and aerospace.  
First, improving the precision of jetting control will be one of the core drivers of technological progress. By optimizing the design of droplet jetting equipment, improving printhead structure, and applying more advanced control algorithms, the precision of droplet size and jetting position can be significantly improved, thereby enhancing the resolution and surface quality of printed products [193]. Precise control over droplet formation and deposition helps address current issues related to layer thickness control and edge effects, ensuring superior performance in the high-precision manufacturing of complex structures. Secondly, increasing printing speed and efficiency is key to enabling industrial application of this technology. In this regard, future advancements may involve improving layer thickness process planning, implementing grayscale printing, optimizing material supply systems, and utilizing new high-speed droplet jetting printheads. These methods can significantly reduce the printing cycle, especially in the production of large-size and complex geometric structures [194]. This improvement will not only enhance production efficiency, but also increase the feasibility of SiC powder 3D printing technology for large-scale production. Additionally, material diversification and functional integration will be key research directions in the future. The application of SiC powder 3D printing technology will expand from single materials to functional composites, smart materials, and nanomaterials, helping to overcome the limitations of traditional materials and achieve functional integration in printed products. By integrating new materials with intelligent design, future printed products will possess various integrated functions, such as sensing and thermal management [195; 196; 197]. Moreover, the development of intelligent and automated control technologies will further advance droplet jetting technology. With the integration of artificial intelligence, machine learning, and sensor technologies, future printing processes will enable real-time data collection and feedback control. By continuously monitoring and adjusting jetting parameters and material conditions in real time, the printing process can be optimized to ensure product consistency and quality [198]. Such data-driven adaptive control systems are expected to enable full automation of the droplet jetting 3D printing process, improving production efficiency while ensuring the stability of product quality.
## 2 Materials and Methods
### Antifungal Activity of Calendula officinalis Water Extract In Vitro  
#### 2.6.1 Direct Contact Assay  
The effect of the _Calendula officinalis_ water extract on mycelial growth was studied according to the methodology described by [PERSON] and [PERSON] [20]. Twenty millilitres of YPD medium supplemented with _Calendula officinalis_ water extract (5 mg/mL) at 5%, 10%, and 15% (\(v/v\)) were poured into sterilized Petri dishes (inner diameter 90 mm). After the medium had solidified, it was inoculated centrally with a 10-day-old culture of fungi _A. niger_ and _Penicillium_ sp. discs (5 mm in diameter). Control was the Petri dishes with pure YPD medium inoculated similarly. The Petri dishes were incubated at 28 \({}^{\circ}\)C. The experiment was performed in triplicate.  
The effect of _Calendula officinalis_ water extract on the mycelial growth of the tested fungi after 3, 5, and 7 days was calculated from the formula:  
\[\text{Inhibitory activity }\%=(C-T)/C\times 100\%\]  
where C and T are the average diameters (mm) of fungal mycelia in the control and the treatment, respectively.  
2.6.2. Influence of _Calendula officinalis_ Water Extract on Fungal Biomass Production Preparation of Spore Suspension of _Aspergillus niger_ and _Penicillium_ sp.  
_Aspergillus niger_ and _Penicillium_ sp. were kept on YPD medium plates at 28 \({}^{\circ}\)C. Spores of fungus were harvested from 10-day-old cultures in Ringer's solution (peptone 1 g, NaCl 8 g per 1 L of distilled water; pH 6.9 \(\pm\) 0.2) and loosened by 15 min shaking. The suspension was adjusted to 1 \(\times\) 10\({}^{6}\) spores/mL.  
Fungal Biomass Production  
The biomass growth of tested fungi was carried out in 200 mL Erlenmeyer flasks per 100 mL of YPG medium (10 g yeast extract, 20 g peptone, 20 g glucose per 1 L of distilled water; pH 6.0 \(\pm\) 0.2), in which part (5%, 10%, and 15%) was replaced with a previously prepared _Calendula officinalis_ water extract, according to the methodology of [PERSON] [20] with some modifications. One mL of the prepared spore suspension of the tested fungi was added to each flask. The control was the flask with pure YPG medium inoculated in the same way. The flasks were incubated at 28 \({}^{\circ}\)C for 7 days and at 150 rpm in a shaking incubator. After the incubation period, the contents of each flask were filtered through standard filter paper (each filter had been weighed). The harvested mycelium was dried at 80 \({}^{\circ}\)C until a constant weight was obtained. The fungal biomass of each treatment was weighed and compared with the control. The experiment was performed in triplicate.  
The influence of _Calendula officinalis_ water extract on fungal biomass production was calculated by using the formula:  
\[\text{Inhibitory activity }\%=((\text{Wbc}-\text{Wbt})/\text{Wbc})\times 100\%\]  
where: Wbc is the weight of biomass control, and Wbt is the weight of biomass treatment.
# How Soft Polymers Cope with Cracks and Notches
## 1 Introduction
In such materials, the rupture process is strongly influenced by the fluid interaction [22], and it has been discovered that increased toughness and fatigue resistance are obtained through the development of polymer networks containing chains of different lengths (such as the double-network hydrogels, containing both a short- and a long-chain highly stretchable network). In this fashion, the shortest chains act as sacrificial elements, while the longer ones provide the material with a further elastic behavior [23; 24]. From this perspective, it appears that the polymer network characteristics play a crucial role in defining the macroscopic behavior of the material. Furthermore, soft materials are sensible to time-dependent effects, with the fracture energy depending on the rate of application of the external loads, because of the viscous energy dissipation occurring in the crack tip region [25; 26; 27]. Sometimes, under a constant applied load, a so-called delayed fracture has been observed, depending on the network structure of the soft matter [28]. In this work we present a comprehensive investigation into the defect tolerance of flawed specimens of rubber-like polymers, with a detailed summary of experimental findings recently published by the authors [29; 30; 31]. Various configurations with cracks and notches are examined in order to evaluate the macroscopic mechanical response in relation to the flaw severity. Moreover, the effect of the applied strain rate is taken into account phenomenologically. All the experimental tests are conducted under strain control, and the kinematically-related quantities are measured through a contactless Digital Image Correlation (DIC) technique. Due to the local high deformations in proximity of the defects, a severe defect remodeling with evident blunting is noticed. The main purpose is to show how crack blunting affects the rupture behavior of soft materials. Through a simplified analytical model, the increase in the curvature radius at the notch root with the remote applied load is described. Such a model is applied to the experimental results, putting into evidence that it is the blunting effect which controls the rupture process; in particular, the grade of blunting appears to determine the transition from the typical small-scale yielding failure to rupture at a constant theoretical strength. The paper is organized as follows. Section 2 presents a collection of the results obtained from the experiments, with details on the materials and methods employed. Accurate images taken from the DIC elaboration are included. In Section 3, a detailed discussion is developed in order to give a comprehensive interpretation of the experiments, with specific reference to the notch blunting effect, which is computed through a simplified analytical model. Finally, Section 4 sets out the conclusions.
###### Abstract  
The search for more sustainable construction materials, capable of complying with quality standards and current innovation policies, aimed at saving natural resources and reducing global pollution, is one of the greatest present societal challenges. In this study, an innovative recycled aggregate concrete (RAC) is designed and produced based on the use of a coarse recycled aggregate (CRA) crushing concrete with electric arc furnace slags as aggregate. These slags are a by-product of the steelmaking industry and their use, which avoids the use of natural aggregates, is a new trend in concrete and pavement technology. This paper has investigated the effects of incorporating this type of CRA in concrete at several replacement levels (0%, 20%, 50% and 100% by volume), by means of the physical, mechanical and durability characterization of the mixes. The analysis of the results has allowed the benefits and disadvantages of these new CRAs to be established, by comparing them with those of a natural aggregate concrete (NAC) mix (with 0% CRA incorporation) and with the data available in the literature for concrete made with more common CRA based on construction and demolition waste (CDW). Compared to NAC, similar compressive strength and tensile strength values for all replacement ratios have been obtained. The modulus of elasticity, the resistance to chloride penetration and the resistance to carbonation are less affected by these CRA than when CRA from CDW waste is used. Slight increases in bulk density over 7% were observed for total replacement. Overall, functionally good mechanical and durability properties have been obtained.  
recycled aggregate concrete; electric arc furnace slags; mechanical properties; durability 1