esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results and Discussion  
### Operating Conditions and Cases Analyzed  
The objective of this study was to analyze the kinetics of polymer network formation by nitroxide mediated copolymerization (NMC) of styrene and divinylbenzene carried out in scCO\({}_{2}\). FRP and NMP of STY and conventional FRC of STY/DVB were also considered in the study as reference systems useful in the analysis. The polymerizations reported in this study, which are summarized in Table 1, proceeded at a temperature (T) of 120 \({}^{\circ}\)C and pressure (P) of 207 bar, using Krytox 257 FSL as a stabilizer. The chemical structure of Krytox 257 FSL is shown in Scheme 1. As shown in Table 1, eight case studies were considered in this contribution, all carried out in scCO\({}_{2}\). Case 1 deals with FRP of STY, whereas Case 2 concerns the NMP of STY, and Case 3 refers to conventional FRC of STY DVB. These three cases are reference cases. Cases 4 to 8 concern the NMC of STY and DVB at different crosslinker and controller concentrations.  
\begin{table}
\begin{tabular}{c c c c} \hline
**Case** & **Description** & **[DVB] (wt.\%)** & **[TEMPO]/[BPO] a ** \\ \hline
1 & FRP of STY & 0 & 0 \\
2 & NMP of STY & 0 & 1.1 \\
3 & FRC of STY/DVB & 1 & 0 \\
4 & NMC of STY/DVB & 1 & 1.1 \\
5 & NMC of STY/DVB & 1.5 & 1.1 \\
6 & NMC of STY/DVB & 3 & 1.1 \\
7 & NMC of STY/DVB & 1 & 1.6 \\
8 & NMC of STY/DVB & 1 & 3 \\ \hline \end{tabular}
\end{table}
Table 1: Cases of homopolymerization of STY and copolymerization of STY/DVB in scCO\({}_{2}\), either conventional or NMP.  
Figure 1: Sketch of the reacting system for NMC of styrene and divinylbenzene in scCO\({}_{2}\).
# The Shear Behavior of the Curved Interface in Polyurethane-Concrete Composite Structures
## 3 Results and Discussion
### Comparison of Shear Behavior in Curved and Planar Composite Specimens
#### 3.1.5 Shear Residual Strengths in Curved and Planar Specimens with Varying Polyurethane Densities  
The variations in shear residual strength of curved and planar composite specimens with polyurethane density are shown in Figure 10. For composite specimens with the same polyurethane density, the residual strength of curved specimens is significantly higher than that of planar specimens. As the polyurethane density increases, the residual strength of composite specimens gradually increases. The growth rate of residual strength for curved interfaces increases, while for planar specimens, the growth rate gradually decreases. However, the overall change in growth rate is relatively small, and the residual strength remains largely stable.  
Figure 10: Shear residual strength of curved and planar composite specimens with different polyurethane densities.  
Figure 9: Peak shear displacements of curved and planar composite specimens with different polyurethane densities.
# An Overview of Intelligent Transportation Systems in Europe
## 1 Introduction  
### The Necessity of the Proposed Topic  
Intelligent transport has a significant impact on urban and regional mobility, and is a continuously changing area of modern infrastructure. The present study reviews Intelligent Transport Systems (ITSs) in Europe and analyses their progress, challenges and benefits. ITSs are essential for optimizing transport flows, reducing emissions and improving road safety in today's world, characterized by sustainability objectives and accelerated urbanization. Several studies have examined the development and implementation of Intelligent Transport Systems (ITSs) in Europe, focusing on various aspects such as standardization, technological evolution, policy frameworks and crossnational comparisons.  
[PERSON] (2014) provided a comprehensive overview of the standardization process for Cooperative ITSs (C-ITSs), highlighting how a decade of research and development enabled the launch of connected mobility services [1]. The role of European standardization organizations--the European Committee for Standardization (CEN), the EuropeanCommittee for Electrotechnical Standardization (CENELEC) and the European Telecommunications Standards Institute (ETSI)--in shaping ITS technical and legal frameworks was further emphasized in a historical analysis published by [PERSON] (2012) [2]. [PERSON] (2023) compared ITS standardization policies between Europe and the United States, underscoring the effectiveness of Europe's policy-driven approach [3]. The European Commission's Directorate-General for Mobility and Transport has also documented the importance of ITSs for job creation and innovation, noting the growing influence of technologies such as AI, 5G and blockchain.  
These studies have laid critical groundwork; however, they often focus on isolated topics such as technical standards, historical development or single-country policies. In contrast, the present paper offers an integrated and updated review that examines ITSs in Europe from multiple perspectives--technological, legislative and strategic--while also incorporating case studies and policy implications.
# Loosely Coupled GNSS and UWB with INS Integration for Indoor/Outdoor Pedestrian Navigation +
## 3 Material and Methods
### Hardware  
The data acquisition and navigation process in this work was performed by a single portable platform for pedestrian navigation, composed of various sensors selected for their complementarity in performing indoor/outdoor navigation (Figure 1). The variety and number of the acquired information allows us to investigate and apply different integration methodologies and algorithms to carry out the task of seamless navigation. The core of the multi-sensor platform is the Pozyx accurate positioning system (Pozyx NV, Ghent, Belgium), a UWB-based real-time locating system (RTLS) based on two-way ranging techniques [29]. The hardware is composed by anchor nodes and tag nodes which both use about 180 mA at max update rate. The inertial acquisitions are demanded to an IMU composed by a three-axis accelerometer, three axis gyroscope and three axis magnetometer and also a micro-barometer integrated on the Pozyx rover board. The GNSS module is the u-blox NEO-MST (u-blox, Thalwil, Switzerland), a single frequency, multi-constellation receiver developed for automotive application. The computational load of the positioning estimation algorithm is delegated to a Raspberry Pi 3 Model B+ with Ubuntu OS installed board which manage also the serial communication and the time synchronization of all the sensors. The main characteristic of this system is the very low cost of the sensor which nowadays can be easily found also in new generation smartphones. The total cost of the UWB-based multisensory system is about 6006 comprehensive of the anchors network installation. Table 1 summarize the principal characteristics of these sensors together with their performance and cost.  
Figure 1: The multi-sensor platform used during the data acquisition campaign tracked by two total stations [14].  
To assess the accuracy of the estimation algorithm a reference solution is required. When a kinematic test is conducted, the irregular path of the pedestrian must be tracked with an accuracy much higher than the accuracy of the device to be validated. In this work, the ground truth was acquired with a topographic total station with the ability to autonomously lock to and track a prism target. In particular, two total stations have been used in order to cover both the indoor and the outdoor part of the acquisition (the Leica MS50 and the Trimble S7 tracking a Leica GRZ122 360 degrees prism).
# Ultrasound-Assisted Extraction of \(\beta\)-Asarone from Sweet Flag (_Acorus calamus_) [PERSON]
## 3 Results and Discussions  
### Characterization of \(\beta\)-Asarone  
In this study, the extraction of the volatile \(\beta\)-asarone oil was carried out from the _A. calamus_ rhizomes using two techniques--the conventional solvent extraction and ultrasound-assisted extraction techniques (Figure 1a,b). The major component of the extract and the focus of this study, \(\beta\)-asarone or 1,2,4-trimethoxy-5-(prop-1-en-1-yl)benzene is shown below in Figure 3a. The UV spectrum showed three absorption maxima at 302, 252 and 203 (Figure 3b). The IR spectrum indicated the presence of methyl group C-H stretch (2936 cm\({}^{-1}\)), aromatic ring C-C stretch (1608, and 1508 cm\({}^{-1}\)) and ether C-O stretch (1203 cm\({}^{-1}\)) functional groups (Figure 3c). The _m/z_ is found to be 209.0954 [M+H]\({}^{+}\) (calcd. 209.1172) (Figure 3d).  
The purified \(\beta\)-asarone was further characterized by \({}^{1}\)H and \({}^{13}\)C NMR spectra. Both spectra are shown in Figure 4. The \({}^{1}\)H NMR spectrum displayed eight proton signals. Of the eight proton signals, two signals were observed as a doublet of doublet (dd) at \(\delta\)H 6.46 and 1.82, one signal was observed as multiplet (m) at \(\delta\)H 5.74 and the other five signals were observed as singlet (s) at \(\delta\)H 6.82, 6.51, 3.87, 3.81 and 3.78. The COSY, DEPT, HSQC and HMBC spectra are provided as Figures S2 to S5 in the SI. The COSY spectrum indicated the partial structure -CH=CH-CH3, corresponding to C(7)-C(8)-C(9), hence suggesting the presence of the aliphatic chain substituted at the aromatic rings system. The \({}^{13}\)C NMR spectrum showed the presence of an \(sp^{3}\) primary carbon, three \(sp^{3}\) methoxy carbon, four \(sp^{2}\) tertiary carbon and four \(sp^{2}\) quaternary carbon signals. The carbon signals at \(\delta\)C 56.12, 56.50 and 56.66 indicated the presence of three methoxy carbon, while the \(\delta\)H 14.70 suggested the presence of an \(sp^{3}\) primary carbon. The experimental spectroscopic data (NMR, UV, IR and MS) of \(\beta\)-asarone are similar to the values from the literature [7].  
Figure 2: The HPLC spectrum of \(\beta\)-asarone (1.7 min; \(>\)95% purity).  
The HPLC spectrum of \(\beta\)-asarone at 260 nm (Figure 2) showed two peaks at 1.7 and 2.1 min. The characterization of purified \(\beta\)-asarone is crucial as it is used as a reference for the kinetics study.
# Fine Recognition of MEO SAR Ship Targets Based on a Multi-Level Focusing-Classification Strategy
## 6 Conclusions  
A multi-level focusing-classification strategy is proposed for MEO SAR ship target recognition in this paper. The complex ship focusing process is decomposed into rapid global coarse focusing and local fine focusing. Two classification networks are designed for each focusing stage. Specifically, coarse ship classification is first performed after global coarse focusing, followed by target local region slice selection based on the coarse classification results. The image slices are utilized for the next fine focusing step, and ultimately for fine classification. Local region extraction significantly reduces the amount of data requiring fine focusing, substantially improving processing efficiency. The equivalent MEO SAR ship dataset is constructed by adding MEO ship motion errors to real LEO SAR ship images. The simulated MEO SAR ship data are also generated by echo simulation. The experimental results validate the effectiveness of the proposed method.  
Conceptualization, Z.L. and W.Y.; methodology, Z.L., W.Y., C.S. and J.G.; software, Z.L.; validation, J.G. and C.S.; formal analysis, H.Z.; investigation, Y.W.; resources, H.X.; data curation, Z.L. and H.X.; writing--original draft preparation, Z.L.; writing--review and editing, Z.L. and J.G., visualization, C.S. and J.G.; supervision, W.Y. and H.Z.; project administration, W.Y. and Y.W.; funding acquisition, W.Y. All authors have read and agreed to the published version of the manuscript.  
This research was funded by National Key Research and Development Program of China, grant number 2022 YFB3901601.  
The data presented in this study are available on request from the corresponding author. The data are not publicly available due to privacy.  
The authors declare no conflicts of interest.
# Effects of Matrix Modification on the Mechanical Properties of Wood-Polypropylene Composites
## 1 Introduction
Some reactive comonomers containing more polymerizable groups have also been used as crosslinking agents for polyolefin, owing to their high free-radical reactivity, for strength enhancement. Therefore, to confer superior mechanical properties of composites based on PP matrix modification, these monomers can be used to restrain the degree of PP degradation and to obtain moderate MAH grafting efficiency. This study is, thus far, the first to explore the effect of PP matrix modification on the mechanical properties of wood-polypropylene composites, where using divinyl benzene (DVB) as a second monomer in MAH-grafted PP matrices. In this current study, DVB containing two polymerizable groups was used as an interlinking agent in PP-MAH grafting systems. The matrix with both MAH and DVB was modified with an extruder, and then compounded with WF to prepare the composites. The effects of co-modified PP matrices on the mechanical properties of composites were investigated. In addition, the fiber-matrix interface and the dispersion of wood fibers in the composites were characterized using scanning electron micrographs (SEM) and dynamic mechanical analysis (DMA).
## 1 Introduction
If a PT involves fewer than 30 participating laboratories [12], the ISO 13528:2022 standard [13] and the IUPAC/CITAC guide for selecting and using a PT with a limited number of participants [12], this suggests, whenever feasible, the reference value should be determined using a method that is independent of participants' results or metrologically valid. Metrological traceability ensures that a measurement result is linked to a reference through an uninterrupted and documented chain of calibrations, with each calibration step contributing to the overall uncertainty [14]. A recommended approach for situations with a small number of PT participants is to use a value based on the analysis in a single laboratory through a calibration using Certified Reference Material (CRM) to determine the assigned value. This method aligns with ISO 13528:2022 [13]. Recently, this procedure has been implemented in PT with a low number of participants for determining fat and crude protein content in raw milk but incorporating more analysis sessions and a smaller number of samples [15]. Consequently, it is of interest to evaluate the results of the freezing point PT design while bearing in mind the differences between analytical methods, the number of PT items, the nature of the reference materials and the number of participating laboratories, among other factors. Determining the appropriate uncertainty of the reference value assigned to a PT is crucial. In this study, the criteria outlined in the ISO 13528:2022 standard [13] were applied for this purpose. It is important to highlight that the standard specifies that if the uncertainty of the assigned value is considerable in relation to the standard deviation used for proficiency assessment, participants may receive inaccurate results due to factors unrelated to their actual performance. This standard also states that if the uncertainty of the assigned value is less than 0.3\(\hat{\sigma}\), it could be considered as negligible and need not be considered when interpreting the results obtained from the PT round. The standard also provides options for the evaluation of the participants when this criterion is not met, one of them being the use of \(z^{\prime}\)-scores (as described in the standard), according to which uncertainty is included in the evaluation of performance. The objective of the present work is to investigate the design that has been used for the assignment of reference values in PT rounds on raw milk freezing point conducted in Chile between the years 2017 and 2021 by a small number of participating laboratories and to determine the degree of compliance with the appropriate criteria to establish the assigned value for standard uncertainty set out by ISO 13528:2022 [13]. It also intends to determine the adequacy and validity of the criteria applied in order to calculate the standard deviation for proficiency assessment. This work intends to be a useful model for the assignment of reference values and uncertainty in other PTs with a small number of participants and for other measurands and samples.
# Novel Dual Beam Cascaded Schemes for 346 GHz Harmonic-Enhanced TWTs
## 5 Conclusions  
To develop high-power THz sources, HHTWT operating at 346 GHz is introduced and analyzed in this paper. It can output THz signal by amplifying the fourth harmonic component of E-band RF signal. The simulation results demonstrate that amplifying the fourth harmonic signal is a promising way to obtain high-power THz signal. Furthermore, two power-enhanced schemes, CE-HHTWT and PA-HHTWT, are proposed in this paper. CE-HHTWT yields the THz power by amplifying the signal generated by HHTWT. PA-HHTWT amplifies THz band EM wave by importing high power-level fundamental wave into HHTWT. The operating principle and design methodology of two schemes are also described in this paper, including high frequency characteristics and length determination of each sections. To validate working principle which relies upon [PERSON]'s linear theory, the simulation results are predicted by CST. Driven by two 18.4 kV,10 mW electron beams, CE-HHTWT can generate over 400 mW power in 340-348 GHz by inputting signal of 200 mW from 85 GHz to 87 GHz. The peak power is 1100 mW at 346 GHz. The output power of PA-HHTWT is over 600 mW in 338-350 GHz. The 3 dB bandwidth reaches 16.5 GHz. The simulation results show that CE-HHTWT and PA-HHTWT have advantages in peak power and wide bandwidth, respectively. Compared with conventional THz sources driven by high-power solid-state power amplifier, these two schemes, both constituted by two TWTs, have superiorities in structural strength and costs.  
In future study, CE-HHTWT and PA-HHTWT SWSs can be fabricated by using high-precision CNC milling. Periodic permanent magnet (PPM) and dual-beam electron gun will be adopted in electron optical system. To validate the feasibility of design, the insertion loss, output power, bandwidth, and phase noise characters will be tested. Thus, the schemes of CE-HHTWT and PA-HHTWT are hopeful approaches to realize practical high-power THz sources for plasma diagnostic, communication, and radar.  
Conceptualization, R.Z., H.G., and Q.W.; methodology, R.Z. and H.G.; software, R.Z. and D.D.; validation, R.Z. and Y.D.; formal analysis, R.Z. and H.G.; investigation, R.Z., G.T., and H.G.; writing--original draft preparation, R.Z.; writing--review and editing, R.Z. and F.X. All authors have read and agreed to the published version of the manuscript.  
This work was supported in part by the National Natural Science Foundation of China under Grant 61370152, 61531010 and in part by the American Physical Society's International Travel Grant Award Program.  
The authors declare no conflict of interest.  
Figure 24: Gain property (**a**) and bandwidth property (**b**) of PA-HHTWT.
## 3 Sink Mobility Advantages  
In almost all WSN applications, the sink is considered as an unconstrained entity in terms of resources (energy reserve, processing power, communication capability, _etc._). Likewise, in several applications of sensor networks, sink mobility can be realized by attaching a sink device to a mobile entity such as human, animal, robot, or vehicle which can move around/inside the sensor field for data collection. Thus considerable energy savings can be obtained by deploying a mobile sink in sensor field. [PERSON] _et al._ identified several potential advantages of sink mobility [12] in the sensor field that are outlined as follows:  
_Sensor Lifetime Enhancement_--By exploiting sink mobility, not only is the energy-hole problem alleviated, but it also improves the lifetime of nodes thereby reducing the multi-hop communication. The sensor nodes are considered as energy constrained devices whereas the sink, being external to the network, does not have any energy constraints. Since the communication module is considered the main consumer of a node's energy reserves, if the sink moves closer to the event reporting nodes, greater energy savings could be obtained, thereby limiting the multi-hop communication.  
Figure 2: Network architecture of a mobile wireless sensor network.  
_Improved Coverage_--A mobile sink can potentially cover sparse networks due to its mobility feature and therefore is considered as a cost-effective solution offering deployment of fewer sensor nodes in the sensor field. Similarly, due to its mobility feature, the mobile sink can also pass through problematic areas where there is some obstruction in the propagation path such as large boulders.  
_Improved Throughput and Data Fidelity_--Exploiting sink mobility can also achieve improved throughput and data fidelity. If the sink moves towards the event reporting area, it will not only reduce the number of transmissions but will also reduce the probability of transmission errors and the chances of collisions. Minimizing the chances of retransmissions not only improves network throughout, but also prolongs the network lifetime.  
_Improved Security_--Compared to the static sink scenario, a mobile sink poses less security threats since due to the sink mobility it is relatively difficult to overhear the information. Furthermore, an adversary can obtain the information regarding only a small area due to the reduced number of multi-hop transmissions. Similarly, possible attacks targeting the hub sensor nodes to disrupt network operation are not possible as due to sink mobility, there are no such geo-strategically important nodes that the messages must always pass through.