esa-sceva/satcom-chunk-collection huggingface dataset:
# Effect of Cement Content on the Deformation Properties of Cemented Sand and Gravel Material
## 3 Results and Discussion  
### Stress-Strain and Volumetric Strain-Axial Strain Curves  
The stress-strain and strength characteristics in Figures 1a, 2a, 3a and 4a have been introduced by [PERSON] et al., and these sections will not be discussed here [14]. The slope of the stress-strain curve when the axial strain is 0, called the initial modulus herein, and the strain at point 2 (the peak point of the stress-strain curve), called the failure strain, are key issues in the deformation calculation of CSG dams. Therefore, the effects of various cement contents and confining pressures on the initial modulus and failure strain are studied in this study.  
Figure 4: The curves of the triaxial tests for CSG material with the confining pressure of 1200 kPa: (**a**) the stress–strain curves; (**b**) the volumetric strain-axial strain curves.  
Figure 3: The curves of the triaxial tests for CSG material with the confining pressure of 900 kPa: (**a**) the stress–strain curves; (**b**) the volumetric strain-axial strain curves.  
Figure 2: The curves of the triaxial tests for CSG material with the confining pressure of 600 kPa: (**a**) the stress–strain curves; (**b**) the volumetric strain-axial strain curves.  
It can be seen from Figures 1b, 2b, 3b and 4b that the volumetric strain-axial strain curves of the CSG material before the peak volumetric strain show obvious nonlinearity. When the cement content is low, the shear shrinkage and dilatancy of the CSG material are similar to those of the rockfill material; when the cement content is high, the dilatancy is more obvious, and the initial slopes of the volumetric strain-axial strain curves are less affected by the confining pressure. When the cement content is approximately 100 kg/m\({}^{3}\), the confining pressure has little influence on the initial slope of the CSG material. The volumetric strain and axial strain at point 3 (the peak point of the volumetric strain-axial strain curve) decrease with an increase in the cement content. The volumetric strain-axial strain characteristics of the CSG material above are roughly the same as those of polymer rockfill materials, sand reinforced with fibers, etc. [16; 23].  
As the CSG material begins to exhibit dilatancy at point 3, point 3 is also called the initial dilatancy point. The slope of the volumetric strain-axial strain curve when the axial strain is 0 (point 4) is called the initial tangent volumetric ratio here. These are also key quantities that are considered in the deformation calculation of CSG dams and quantitatively described below.
# Determination of the Crack Propagation Direction in Mixed-Mode Missions due to Cyclic Loading
## 2 Crack Propagation in Tension-Torsion Tests: Experimental Setup
In addition, three different loading type ratios were selected, which result from the quotient of the maximum nominal torsional stress \(\tau_{N}\) to the maximum nominal axial stress \(\sigma_{N}\) in the undisturbed cross-section: \(\tau_{N}/\sigma_{N}=0.76\), 1, and 1.31. Since the axial load level remained constant at the start of all tests, the maximum torsional moments \(M_{t}=60.5\) Nm, 80 Nm, and 104.75 Nm were applied to realize the three \(\tau_{N}/\sigma_{N}\) ratios. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Element** & **C** & **Mn** & **Si** & **P** & **S** & **Cr** & **Mo** & **Ni** & **Al** \\ \hline Composition & 0.36 & 0.73 & 0.26 & 0.006 & 0.001 & 1.57 & 0.22 & 1.57 & 0.022 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Chemical composition (in % of weight) of the tested material 34 CrNiMo6 [39]. Figure 1: Experimental setup: (**a**) geometry of the SEN-TC-specimen; (**b**) servo-hydraulic tension/torsion testing machine [38; 40]. Furthermore, the influence of the stress ratio of the axial load on the crack propagation behavior under mixed-mode conditions was investigated. For this purpose, tests were carried out both at \(R_{axial}=0\) and \(R_{axial}=-1\). The stress ratio of cyclic alternating torsion was \(R_{torsion}=-1\) in all experiments. In order to investigate the influence of a non-proportional mixed-mode load on the fatigue crack propagation, the torsional moment was set in-phase to the tension-compression load, as well as phase shifted by \(40^{\circ}\) and \(90^{\circ}\) to the axial loading. In total, there were eighteen different load cases, which result from the superposition of an axial load with a torsional moment from the schematic diagram for one load cycle in Figure 2.  
All experiments were performed load controlled at room temperature. A change of the twisting angle of the torsion cylinder by more than \(1^{\circ}\) was considered to be the termination criterion.
## Appendix L Description of Mechanisms for Vehicles
### Reputation-Based DPoS [634]  
The proposed consensus mechanism for the vehicular domain follows DPoS mechanics by employing a multi-weight reputation system. Reputation per participant is initialised as a constant and, subsequently, can be updated through interactions with other participants. The selection of miners within the vehicular network is based on these reputation values with a higher reputation value corresponding to a greater chance of being selected as a miner. Complex Sybil attacks would not be preventable by such a reputation system, as a malicious participant could create multiple entities to then undertake manipulative interactions with the goal of increasing the reputation of a single entity.
# Comprehensive Annual Ice Sheet Velocity Mapping Using Landsat-8, Sentinel-1, and RADARSAT-2 Data
## 2 Data and Methods
### Greenland  
#### 3.2.1 Landsat-8  
In Greenland, we processed 3783, 13063 and 9257 Landsat pairs for years 2013-2014, 2014-2015, 2015-2016 and assembled the mosaics shown in Figure 3a-c. Correlation increases with latitude,  
Figure 2: Annual mosaics of surface ice speed generated from Landsat-8 (**A–C**) and the SAR sensors Sentinel-1 and RADARSAT-2 (**D–F**) in Antarctica. The figure is constructed as a matrix, the 3 rows representing the different years surveyed (2013, 2014, 2015) and the 2 columns representing the different sensors (optical and SAR). The ice velocity is coded on a logarithmic scale overlaid on MOA background mosaic [(32)]. Each velocity map is accompanied by 3 additional panels representing the number of velocity measurements (**top**), the weighted standard deviation in x- (**middle**) and y-direction (**bottom**). Standard deviations are calculated when 3 or more velocity measurements are present and replaced by the weighted standard error when less than 3 measurements are found.  
allowing a more complete mapping of the northern part of Greenland. Surface features in the interior of the ice sheets seem to be less persistent than in Antarctica, thus strong decorrelation occurs for 64 days repeat cycle. As a result, the standard deviations are larger than those estimated in interior Antarctica, typically 10 to 20 m/year.  
Figure 3: Annual mosaics of surface ice speed generated from Landsat-8 (**A–C**) and the SAR sensors Sentinel-1 and RADARSAT-2 (**D–F**) in Greenland. The figure is constructed as a matrix, the 3 rows representing the different years surveyed (2013, 2014, 2015) and the 2 columns representing the different sensors (optical and SAR). The ice velocity is coded on a logarithmic scale overlaid on MOG background mosaic [33]. Each velocity map is accompanied by 3 additional panels representing the number of velocity measurements (**top**), the weighted standard deviation in x- (**middle**) and y-direction (**bottom**). Standard deviations are calculated when 3 or more velocity measurements are present and replaced by the weighted standard error when less than 3 measurements are found.
###### Abstract  
Developing efficient communication between vehicles and everything (V2X) is a challenging task, mainly due to the characteristics of vehicular networks, which include rapid topology changes, large-scale sizes, and frequent link disconnections. This article proposes a deep learning model to enhance V2X communication. Various channel conditions such as interference, channel noise, and path loss affect the communication between a vehicle (V) and everything (X). Thus, the proposed model aims to determine the required optimum interference power to enhance connectivity, comply with the quality of service (QoS) constraints, and improve the communication link reliability. The proposed model fulfills the best QoS in terms of four metrics, namely, achievable data rate (\(R_{0}\)), packet delivery ratio (PDR), packet loss rate (PLR), and average end-to-end delay (E2E). The factors to be considered are the distribution and density of vehicles, average length, and minimum safety distance between vehicles. A mathematical formulation of the optimum required interference power is presented to achieve the given objectives as a constrained optimization problem, and accordingly, the proposed deep learning model is trained. The obtained results show the ability of the proposed model to enhance the connectivity between V2X for improving road traffic information efficiency and increasing road traffic safety.  
vehicle-to-everything QoS; reliability; achievable data rate; deep learning; 1D-CNN accepted: 29 November 2021  
1 2021
# Cellulose Nanofibril (CNF) Films and Xylan from Hot Water Extracted Birch Kraft Pulps
###### Abstract  
The effects of xylan extraction from birch kraft pulp on the manufacture and properties of cellulose nanofibril (CNF) films were here investigated. Hot water extractions of bleached and unbleached kraft pulps were performed in a flow-through system to remove and recover the xylan. After the extraction, the pulps were oxidized with 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and fibrillated in a high-pressure microfluidicer. Compared to CNF from bleached kraft pulp, the CNF dispersions obtained from water-extracted pulps were less viscous and generally contained a higher amount of microfiber fragments, although smaller in size. In all cases, however, smooth and highly transparent films were produced from the CNF dispersions after the addition of sorbitol as plasticizer. The CNF films made from water-extracted pulps showed a lower tensile strength and ductility, probably due to their lower xylan content, but the stiffness was only reduced by the presence of lignin. Interestingly, the CNF films from water-extracted bleached pulps were less hydrophilic, and their water vapour permeability was reduced up to 25%. Therefore, hot water extraction of bleached birch kraft pulp could be used to produce CNF films with improved barrier properties for food packaging, while obtaining a high-purity xylan stream for other high-value applications.  
barrier properties; CNF film; hot water extraction; nanocellulose; xylan +
Footnote †: journal: Applied Sciences
# MODIS Retrieval of Aerosol Optical Depth over Turboid Coastal Water
## 3 Retrieval Algorithm
### Algorithm Implementation and Steps
Conduct gas (H\({}_{2}\)O, CO\({}_{2}\), and O\({}_{3}\)) correction [4] for the remaining pixels. 4. Calculate the mean 2.1 \(\upmu\)m TOA reflectance if there are still no less than 10 pixels. Otherwise retrieval is not conducted. Calculate the sun glint angle [9]. If the sun glint angle is less than 40\({}^{\circ}\), the retrieval is not conducted. 5. Prescribe single scattering properties of the aerosol. By only using 2.1 \(\upmu\)m reflectance to retrieve AOD, there is no sensitivity to aerosol optical properties. Figure 4 shows that AOD can differ up to 0.2 in 100 km from the coast, but FMF differs only by 0.08 in 100 km from the coast. Thus, we assume the single scattering properties (including FMF) and surface wind speed for a turbid coastal water pixel is the same as those used for the AOD retrieval by the standard MODIS algorithm over its closest open-ocean pixel (within 100 km radius). The assumption that aerosol type does not change over moderate spatial scale is reasonable and was used in the atmospheric correction of SeaWiFS imagery over turbid coastal waters [19]. 6. Use the mean 2.1 \(\upmu\)m TOA reflectance and lookup table determined by Equation (1) to retrieve AOD over the turbid coastal water where MxD04 product is unavailable. In application of Equation (1), all ancillary information (aerosol mode selection and FMF) is obtained from step 5. Figure 3: Flowchart of retrieving AOD over coastal water.
## 1 Introduction
The novel method combines different numbers of beams by using different CDG, such as 3 \(\times\) 3 CDG, 4 \(\times\) 4 CDG, and 5 \(\times\) 5 CDG, which solves the problem of weak beam energy mentioned above. Moreover, the coherent array beam parameter of CDG and Fresnel diffraction distance can also be used as the encryption key. In this scheme, eight QR codes are superimposed by bit plane, and each QR code stores an image. Random scrambling is carried out to hide the outline of the superimposed QR code. Then, the scrambled image is randomly divided into four pieces, each of which is multiplied by the corresponding Dammann phase (DP) complex conjugate. Finally, they are decomposed into ciphertexts and keys by EMD in turn. Compared with the other optical encryption system, our optical system has the following advantages. First, the one-period length of CDG can be used as one of the keys for encryption. Second, the coherent superposition is more superior to the incoherent superposition, introducing more encryption keys, such as Fresnel diffraction distance, thus more capable of resisting cryptosystem attacks. Third, the power of the combined beam is higher than the conventional methods, which is thus easy to detect. Fourth, the QR codes can ensure that the encrypted images are able to be decrypted without image quality loss. The organization of our paper is given as follows. In Section 2, theories involved in the research are introduced and described. The simulation results of our encryption system are given in Section 3. Relevant discussions are carried out in Section 4, followed by a conclusion of the research in Section 5.
## 3 Results and Discussion
### Performance of Multi-GNSS Static PPP Survey with CNES/CLS (Test A)  
The measurements of Test A are processed with the PPP technique. In order to maintain the data consistency, precise orbits and clock products from CNES/CLS are adopted; clock data with a sampling of 30 s are used.  
In Table 5, the results obtained processing GPS-only measurements with the PPP technique are shown. The results are expressed in terms of daily solution standard deviations and final solution errors. In order to assess the effect of the usage of precise clock data at 30 s (second line of Table 5), a comparison is carried out with the performance of standard GPS-PPP using clock data at 15 min (first line of Table 5). For all the considered configurations, the Estimate ZTD tropospheric model and the previously mentioned outlier rejection strategy are used.  
Comparing the lines 1 and 2 of Table 5, it is evident that using precise clock products at 30 s provides significant benefits in terms of both standard deviation and error; indeed, all the considered figures of merit are reduced by one order of magnitude.
# UV-Induced Aging in Thermochromic Pigment-Integrated Food-Grade Polymers: A Performance Assessment
## 2 Materials and Methods
### Statistical Analyses  
Statistical methods were used to rigorously assess variation in mechanical, colorimetric, and physical properties after UVA exposure. All datapoints were retained without outlier exclusion to preserve dataset integrity. Sample sizes (\(n\) = 5 or \(n\) = 10) were specified for each test to ensure clarity and reproducibility. Minitab(r) 21.4.1 Statistical Software (Minitab, LLC, State College, PA, USA) was used to perform normality tests and determine whether the observed differences warranted statistical significance. A one-way analysis of variance (ANOVA) was conducted on quintuplicate or deculplicate datasets, depending on the test type. The results were reported as the means \(\pm\) standard deviations. Post hoc Tukey HSD comparisons were applied where applicable, using a significance level of \(p<0.05\)and 95% confidence intervals to assess group differences. These analyses supported the interpretation of UV-induced changes in color difference, tensile behavior, impact strength, and mass stability. Findings were evaluated for both statistical significance and their implications for practical application.
# Natural Motion for Energy Saving in Robotic and Mechatronic Systems
## 2 Mechanical Design for Natural Motion
### Serial Compliance Elements  
Serial elastic elements can be added to a robotic system by connecting an electric motor to a joint by means of an elastic element (see Figure 1a). Such an arrangement is not simply obtained by adding a spring between them but instead by substituting stiff actuators with compliant ones. Series elastic actuators (SEA), first introduced by [PERSON] in Reference [36], are constituted of a linear compliant element between a high impedance actuator and the load. Their use is demonstrated to be beneficial in compliant actuation, energy storage, interaction safety, in the absorption of contact shocks and in the reduction of the peak forces due to the impacts in bipedal walking robots [36; 37]. Examples of SEA for minimizing energy consumption can be found in References [38; 39]. In these works, a convex optimization problem is presented for the design of a SEA capable of energy regeneration such that energy consumption and peak power are minimized for arbitrary periodic reference trajectories.  
The main drawback of SEA is that the stiffness is fixed and cannot be changed during motion, thus limiting the level of compliance to adapt for several tasks. To overcome this problem, a novel class of actuators was proposed: the variable stiffness actuators (VSA). These actuators consist of a motor connected to the output link by a spring in series, whose stiffness is variable. Therefore, the stiffness can be properly controlled to reduce energy requirements during the execution of repetitive tasks, as explained in Reference [40]. Reviews on variable stiffness actuators can be found in References [41; 42; 43; 44], whereas a comparison of several design of VSA based on spring pretension is illustrated in Reference [45].  
VSA were first introduced to decrease contact shocks, to enhance soft collisions in human-robot interaction [46; 47] and to efficiently actuate legged locomotion systems [48; 49]. Furthermore, they were employed to decrease energy consumption in cyclic operations of robotic systems. An example is given by the actuator with adjustable stiffness proposed by [PERSON] et al. [50; 51; 52].
# Analysis of Climate-Oriented Researches in Building
## 3 Results and Discussion
### Results of Cluster Analysis
#### 3.2.3 Cluster 3--Combined Heating, Cooling and Power Systems
In the research of [PERSON] et al., the authors developed and compared the use of optimal CHP systems for four types of buildings (hotel, school, office and hospital) in five cities in China, with different climates in the context of three objectives (ES, OCR and EIM). The authors concluded that energy demands depend on the type of building, which also affects the optimal design of the CHP. In general, throughout the year, the CHP system in office buildings consumes less energy, spends less and emits less CO\({}_{2}\) among the four categories of buildings. In terms of saving primary energy, CHP systems are optimal for severe cold climates; in terms of reducing carbon emissions, they are optimal for mild climates [87]. In 2012, the possibility of applying CHCP systems in a multi-storey residential building, under the climatic conditions of Shanghai City, was analysed. The authors summarised that, from an economic point of view, the introduction of these systems is not profitable for residential buildings and that a reduction in natural gas prices may make it possible to use these systems in such buildings [114]. On the other hand, in Spain, the design of the integrated hybrid solar thermal (PV) micro-CHP system was analysed and applied to an apartment building in five climate zones. In this paper, a discussion was presented on the problems of using micro-CHP systems in residential buildings, and it was concluded that CHP systems are optimal for cold climate zones [115]. The evolution of the application of CHCP systems for different types of buildings is remarkable. Initially, these systems were used for airport buildings and other types of public buildings. Recently, researchers have been analysing the possibility of applyingthese systems to residential buildings. In addition, it is significant that the timing and mode of operation of these systems depend on the type of building, climate zones and target (energy saving, economic or ecological) that is most desired with the use of CHCP systems.
## 3 Classification of Systems
### Number of Power Transmission Paths Parallel to the CVU  
If every input unit in the hybrid system has a unique transmission path with no transmission path parallel to the CVU, the system is called a single-path system. Figure 8 shows four examples of single-path systems with different coupling patterns and transmission units. Since there is no transmission unit parallel to the CVU, the ratio coverage of the system is equivalent to that of the CVU if there is no other transmission unit with a variable ratio.  
Most of the studied hybrid systems [5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31] have no transmission mechanism parallel to the variator. This means that the power flow from the power source(s) must pass through the CVU. Therefore, the maximum allowable torque and power of the system are also confined by the CVU. If at least one transmission path is parallel to the CVU and at least one input unit can drive the wheel(s) through both of them, the system is called a dual-path system. However, if the above parallel transmission path allows the power to transfer only within the system, such as starting the ICE with the M/G or driving the M/G by the ICE for recharging, the system will not be considered a dual-path system.