esa-sceva/satcom-chunk-collection huggingface dataset:
## 3 Results and Discussion
### Analysis of the Effects of YLDI on the Volatile Compounds of Green Tea Using GC-MS/MS
#### 3.3.3. OAV Analysis  
It is universally acknowledged that not all volatile components exert influence on the overall profile of green tea. To screen the pivotal aroma contributors in tea samples exposed to five varying light intensities, OAV analysis was carried out. In general, volatile compounds exhibiting OAV \(\geq\) 1 are deemed as important contributors to the comprehensive aroma, with higher OAV values indicating a stronger contribution [22]. In this investigation, 21 volatile constituents exhibiting OAV \(\geq\) 1 were identified in the tea samples exposed to five distinct light intensities (Figure S3 and Table S5). The top eight volatiles with OAV > 50 in five treatments included (_E_, Z)-2,6-nonadien (OAV: 893.58 \(\sim\) 899.69), \(\beta\)-damascenone (OAV: 467.90 \(\sim\) 840.63), \(\beta\)-ionone (OAV: 305.00 \(\sim\) 448.11), phenylethyl alcohol (OAV: 170.00 \(\sim\) 436.70), linalool (OAV: 88.02 \(\sim\) 152.93), (_E_, _E_)-2,4-decadienal (OAV: 92.09 \(\sim\) 99.30), (_E_, _E_)-2,4-nonadienal (OAV: 48.81 \(\sim\) 66.27), and phenylacetaldehyde (OAV: 50.18 \(\sim\) 75.85). Notably, \(\beta\)-ionone, (_E_, _E_)-2,4-nonadienal, and (_E_, _E_)-2,4-decadienal exhibited higher OAV values in floral aroma samples exposed to 4000 Lux and 6000 Lux compared to the other three treatments. Additionally, phenylacetaldehyde and linalool attained the highest OAV values (75.85 and 152.93, respectively) under 6000 Lux treatment. These key odorants contributed significantly towards elucidating the floral aroma of green tea, corro  
Figure 3: PLS-DA results of volatile compounds in tea samples exposed to yellow light with different intensities based on GC-MS/MS. (**A**) Score plots (R\({}^{2}\)Y = 0.982, Q\({}^{2}\) = 0.896); (**B**) Permutation tests with 200 iterations (R\({}^{2}\) = 0.562, Q\({}^{2}\) = \(-\)0.528); (**C**) Heatmap visualization constructed with VIP > 1.  
orating the findings of [PERSON] et al. (2018) and [PERSON] et al. (2018). Interestingly, the OAV of meridold was greater than 1 only in tea samples treated with 4000 Lux, while citral exhibited an OAV > 1 exclusively in tea samples treated with 1000 Lux. Additionally, 2-methyl-propanal demonstrated the highest OAV in the tea samples treated with 1000 Lux.
## 1 Introduction
### Contributions  
Motivated by the aforementioned, in this paper, we introduce a lower signaling overhead channel selection scheme in hybrid FSO/RF SAGIN, which actually represents a low-complexity network selection technique. More specifically, the contributions of this paper are summarized as follows:  
* A new channel selection scheme has been proposed and used in a hybrid FSO/RF SAGIN dual-hop communication scenario. The new scheme is designed to offer reduced overhead signaling with satisfactory performance.
* For the new scheme, the Markov chain theory has been employed to derive exact analytical expressions for the statistics of the end-to-end output SNR. The analysis presented also takes into account the impact of atmospheric turbulence and pointing errors (for the FSO link) as well as multipath fading and shadowing (for the RF link).
* In the high SNR regime, simpler asymptotic closed-form expressions are also provided, which have been used to elaborate on the physical insights of the considered scenarios.
* The analytical results derived are used to study the OP of the proposed scheme, while the signaling overhead has also been quantified using the criteria of average number of links estimation (NLE) and switching probability (SP).
* The numerical evaluated results presented reveal the reduction in the computational complexity (in terms of signaling overhead), which results in important energy savings without significantly affecting the system's performance.  
The remainder of this paper is organized as follows. In Section 2, the system and channel models, as well as the mode of operation of the network selection technique proposed, are presented. In Section 3, a Markov chain-based analytical framework is presented which is used to investigate the end-to-end OP. In Section 4, various numerically evaluated results are presented and discussed, while in Section 5, the conclusions can be found.
# The Bivariate Empirical Mode Decomposition and Its Contribution to Grinding Chatter Detection
## 1 Introduction
### Hilbert Transform  
Through the BEMD method, the chatter signal can be decomposed into a number of complex-valued IMF components. Thereby, the Hilbert transform can be used to obtain the Hilbert and marginal spectrum distributions [30]. The Hilbert transform is defined as,  
\[x_{k}(t)=\frac{1}{\pi}P\int\limits_{-\infty}^{\infty}\frac{\text{Re}(c_{k}( \tau))}{t-\tau}d\tau\text{ and }y_{k}(t)=\frac{1}{\pi}P\int\limits_{-\infty}^{\infty}\frac{\text{Im}(c_{k}( \tau))}{t-\tau}d\tau \tag{8}\]  
where \(P\) is the Cauchy principal value.  
Define \(X(t)\) and \(Y(t)\) from \(c(t)\) as follows:  
\[X_{k}(t)=\text{Re}(c_{k}(t))+ix_{k}(t)\text{ and }Y_{k}(t)\ =\ \text{Im}(c_{k}(t))\ +\ iy_{k}(t) \tag{9}\]  
so that the amplitude and phase functions can be defined:  
\[Z_{k}(t)=a_{k}(t)+ib_{k}(t)=\sqrt{\text{Re}^{2}(c_{k}(t))+X_{k}^{2}(t)}+i\sqrt {\text{Im}^{2}(c_{k}(t))+\text{Y}_{k}^{2}(t)}, \tag{10}\]  
\[\psi_{k}(t)=\theta_{k}(t)+i\varphi_{k}(t)=\tan^{-1}\frac{X_{k}(t)}{\text{Re}( c_{k}(t))}+i\tan^{-1}\frac{Y_{k}(t)}{\text{Im}(c_{k}(t))} \tag{11}\]  
where \(\theta_{k}(t)\) represents the phase of the real-part IMF, and \(\varphi_{k}(t)\) represents the phase of the imaginary-part IMF.  
Then, the instantaneous frequency can be expressed as follows:  
\[f_{k}(t)=\omega_{k}(t)+i\delta_{k}(t)=\frac{d\theta_{k}(t)}{dt}+i\frac{d \varphi_{k}(t)}{dt} \tag{12}\]  
Thus, the Hilbert spectrum can be obtained:  
\[H(\omega,\delta,t)=\text{Re}(\sum\limits_{k=1}^{n}{a_{k}(t)e^{j\int\omega_{k} (t)dt}})+i\text{Re}(\sum\limits_{k=1}^{n}{b_{k}(t)e^{j\int\delta_{k}(t)dt}}) \tag{13}\]The Hilbert spectrum represents the signals as a function that combines time and frequency. If \(H(\omega,\delta,t)\) is integrated over time, the corresponding marginal spectrum is obtained:  
\[h(\omega,\delta)=\int\limits_{-\infty}^{\infty}H(\omega,\delta,t)dt \tag{14}\]  
The marginal spectrum expresses the amplitude of each frequency in space, and represents the accumulated amplitude in a statistical sense.  
Although the Hilbert transform can analyze the instantaneous frequency, its applicability is restricted by the form of the original signal. For poorly formed signals, such as very irregular signals, the results produced by Hilbert transform differ significantly from the actual physical status. However, after BEMD decomposition, the IMFs have superior characteristics with a small bandwidth, reasonable symmetry, and smooth envelope changes, which are suitable for the Hilbert transform [31]. Thus, the BEMD method and Hilbert transform are highly connected.
# Context-Based Geodesic Dissimilarity Measure for Clustering Categorical Data
## 4 Results  
For illustrative purposes, we first present a simple example of calculating the association-based dissimilarities between two values in a categorical variable using an artificial dataset. Secondly, we demonstrate the development of the mutual \(k\)-nearest neighbor graph with various \(k\) values. Then, finally, we conducted experiments to study the characteristics of the proposed method (CGD) and compared it with other conventional categorical distance measures in the literature: Gower distance (GD) [5], association-based dissimilarity (AD) [8], and a variant of the geodesic distance using Gower distance (hereafter, Gower-based geodesic distance (GGD)).  
These four different dissimilarity measures can be categorized in terms of context/non-context for consideration of correlations and compactness/connectivity for similarity concepts, as shown in Table 1.
## 4 Discussion  
From the result of the simulation of the previous permeability test, the drainage layer with a permeability of \(10^{-10}\) m\({}^{2}\) was chosen as the optimal permeability value. The scaled model was built for the IRD system test and its applicability was verified by applying various rainfall intensities and rainfall durations. As the rainfall duration increased, the surface runoff remained relatively constant with an average of 0.941, 0.942, and 0.943. Under the same rainfall depth condition, the infiltration was reversed when the volume of porous media was not sufficient. In the results of the scaled model simulation, the dimensionless values of surface runoff were almost constant at about 0.94 despite the change in rainfall duration. In the case where the product of total rainfall and duration is the same, that is, where the rainfall depth is the same, the runoff characteristics according  
Figure 21: Results of Inflow rate.  
Figure 22: Comparison of IRD system prototype model.  
to the rainfall intensity of the IRD system were identified. That is, in the case of a rainfall depth of 27.6 mm, the penetration result increased by 16.8% on average and 10.8% on average as rainfall intensity increased. For a rainfall depth of 55.5 mm, the magnitude of surface runoff decreased by up to 23.7% and up to 43.4%. As such, it is judged that the result that the infiltration result was calculated in the opposite way was because the infiltration area was not sufficiently secured compared to the amount of rainfall. Therefore, when constructing the IRD system, it is necessary to design the application site considering the rainfall amount and rainfall duration.  
Prototype modeling cases (Pr-Pe2 Sl0, Pr-Pe3 Sl0, and Pr-Pe4 Sl0) were simulated with respect to the permeability of the permeable block, respectively. As a result of the simulation, the total storage rates were simulated to be 88.28, 31.37, and 94.78%, respectively. The permeability of the permeable block of Pr-Pe3 Sl0 was the second biggest one among three of permeability variation cases. Although Pr-Pe3 Sl0 had the second biggest permeability, it had the least retention rate among the three cases. Through the analysis of the relationship of permeability-total drainage time, in the case of Pr-Pe3 Sl0, rainwater stagnated inside the permeable block and in the drainage layer was effectively drained after rainfall. This design can maximize the retention effect of the infiltration type rainwater drainage system that collects and drains rainwater slowly by using the internal pore internal storage function during rainfall. If the IRD system was designed with the test condition of Pr-Pe3 Sl0 (permeable block with no cross slope), infiltration was equivalent to 62% of the total rainfall and 69% was continuously drained up to about 1,200 s under a heavy rain condition. It was concluded that the IRD system can be reduce the burden on the municipal drainage and the quantitative evaluation with 3-D integrated numerical modeling method suggested in this study.
## 2 Materials and Methods
### Welding Process Setup  
The setup allowed the precise control of rotational speed, the tool's tilt angle, and welding speed. For the cases with added material, the portable FSW device utilized a 3 mm diameter PLA rod as a filler material, from SmartMaterials3D (Alcala la Real, Spain). The filler material was driven through a hole in the welding head, which rotated at a programmable speed, while the operator manually guided the tool along the joint line to form the weld.  
Two tool geometries were used (Figure 3a): one with a cylindrical pin and constant cross-section, 3.4 mm in diameter, and another with a truncated conical pin, featuring a 2.2 mm tip diameter and a 4 mm base radius. Both tools were made from 6082 T6 aluminum and mounted on the FSW device (Figure 3b).  
The fabrication parameters were configured according to supplier recommendations and the specimen's geometry (Figure 4a) following the AWS B4.0:2016 standard [39]. The specimens were manufactured using Fused Deposition Modeling (FDM) technology and arranged as shown in Figure 4b. For this, a delta-architecture 3D printer, specifically the Anycubic Kossel Linear Plus (ANYCUBIC Technology Co., Ltd., Shenzhen, Guangdong, China) (Figure 4c), was used. To study the effect of the filling percentage on the welding process, the internal structure was printed using a grid infill pattern with two different densities: 15% and 100% [39]. Each specimen was 3 mm thick, and the edges were prepared to ensure proper alignment for butt joint welding. During the test, the tool temperature was manually measured using an infrared thermometer, Fluke 566 (Washington DC, USA).  
Figure 2: (**a**) The Friction Stir Welding device mounted on a Cartesian vertical milling machine; (**b**) the details of the fixation.  
Figure 5 shows the internal structure of the specimens (grid infill pattern), displayed in orange (grid), oriented in perpendicular directions (0-90\({}^{\circ}\)) with a mesh spacing of 5.33 mm. The unwelded specimen is shown in Figure 5a, while Figure 5b shows the half specimen. Although the highest strength of the specimens is achieved with a \(\pm\)45\({}^{\circ}\) grid, the 0-90\({}^{\circ}\) configuration was chosen to make the analysis of the results easier, as performed by other researchers [40,41]. Also, in Figure 5b, the inner perimeter is highlighted in green, the outer perimeter in red, and the entire specimen is represented in shaded gray, with a total thickness of 3 mm.  
Figure 4: (**a**) Specim geometry dimensions; (**b**) half-specimens arranged in groups of six units on the working surface; and (**c**) Anycubic printer (ANYCUBIC Technology Co., Ltd., Shenzhen, China).  
Figure 3: (**a**) The geometries and dimensions of the tool with a cylindrical pin (Tool 1) and with a truncated conical pin (Tool 2), respectively. (**b**) The tool with a cylindrical pin mounted on the welding equipment.  
Additionally, Table 1 shows the main parameters used during the manufacturing of the specimens using FDM.
###### Abstract  
Rapid urbanization has led to the emergence of urban-rural fringes, complex transitional zones that challenge traditional urban-rural dichotomies. While these areas play a crucial role in urban development, their precise identification remains a significant challenge. Existing methods often rely on single-dimensional metrics or administrative boundaries, failing to capture the multi-faceted nature of these zones. This study introduces a novel \"Scene-Object-Economy\" (SOE) framework to address these limitations and enhance the precision of urban-rural fringe identification. Our approach integrates multisource geospatial big data, including remote sensing imagery, nightlight data, buildings, and Points of Interest (POI), leveraging machine learning techniques. The SOE framework constructs feature from three dimensions: scene (image features), object (buildings), and economy (POIs). This multidimensional methodology allows for a more comprehensive and nuanced mapping of urban-rural fringes, overcoming the constraints of traditional methods. The study demonstrates the effectiveness of the SOE framework in accurately delineating urban-rural fringes through multidimensional validation. Our results reveal distinct spatial patterns and characteristics of these transitional zones, providing valuable insights for urban planners and policymakers. Furthermore, the integration of dynamic population data as a separate layer of analysis offers a unique perspective on population distribution patterns within the identified fringes. This research contributes to the field by offering a more robust and objective approach to urban-rural fringe identification, laying the groundwork for improved urban management and sustainable development strategies. The SOE framework presents a promising tool for future studies in urban spatial analysis and planning.  
urban-rural fringe; remote sensing; machine learning; urbanization; geospatial big data
# Texture Analysis of Near-Infrared Vein Images During Reactive Hyperemia in Healthy Subjects
## 4 Discussion
### Divergence Between Morphology and Texture  
Notably, none of the classical texture parameters followed the same dynamic profile as vein width throughout the protocol. Rather than indicating a limitation, this divergence highlights that texture and morphometry may capture different aspects of the venous response. While vein width reflects macroscopic expansion, texture parameters may be more sensitive to microstructural or organizational features that evolve independently. This supports the idea that structural and textural analyses are not redundant, but complementary, each offering a distinct physiological lens [46; 47]. Despite significant venous dilation, most texture parameters remained globally stable, indicating that the grayscale distribution within the vein projections was not fundamentally altered by passive filling. However, the isolated increase in correlation, alongside the stable entropy, hints at localized reorganization rather than global disruption. Correlation captures regularity in pixel transitions, while entropy reflects overall disorder. Their divergence highlights how different aspects of texture may respond independently to hemodynamic changes. This divergence motivated the development of composite indices that integrate texture parameters with vein size. Our hypothesis was that single texture parameters may not fully capture the complexity of venous adaptation, especially when structure and signal organization evolve at different scales. By expressing textural parameters relative to morphological change, these derived parameters aimed to uncover hidden relationships between expansion and internal signal structure.
## 3 Prioritizing Geo-Spatial Data Collection
### Optimizing Routing  
In order to find an optimal path that covers the road segments identified by the sample points, the road vertices closest to the sample points are selected as actual route stops to be covered by a survey.  
Figure 4: (**A**) Example of a focus map obtained by additive pooling of two normalized layers describing the spatial density of policies with weight w1:0.7 and the estimated seismic hazard in the district, with weight w2:0.3. (**B**) Same focus map computed with weights (0.5, 0.5). (**C**) Same focus map computed with weights (0.1, 0.9). Lower Part: post-event focus maps with increasing weights in order to increase selectivity of the sampling approach. From left to right, weights are, respectively, (**D**) (1, 1,1), (**E**) (2, 2, 2), (**F**) (3, 3, 3) where layer 1: building/policy distribution, layer 2: seismic hazard, layer 3: road blockages.  
The resulting routing problem can be reduced to the Traveling Salesman Problem [23], where a traveler has to pass by all the stops in the most cost-efficient sequence given a cost function and considering restrictions imposed by the road network. The cost factor used within this study is simply the length of a street segment. Therefore, the shortest route across the sample points is considered optimal. Additional cost factors (e.g., travel time, money, _etc._) and restrictions (e.g., street quality, one-way streets, traffic information, _etc._) can, however, be added to the routing operation if such information is available and required. Cost factors and restrictions are defined as attributes of the road network and are spatially resolved at the road segment level. A multiple Dijkstra algorithm [24] is then used to compute the actual sampling route through all the ordered stops.
# Damage Characteristics of Thermally Deteriorated Carbonate Rocks: A Review
## 3 Crack Initiation and Propagation  
[PERSON]'s theory provides a solid base to ascertain the concept of fracture initiation in brittle materials. His work mainly focuses on the initiation of the tensile failure at the tip of the elliptical cracks. He studied the fracture initiation in glass material under biaxial loading. Later on, researchers applied this concept to the rocks subjected to the triaxial loading conditions [68]. This extended work undergoes the analysis of stresses around the minute defects or cracks under a three-dimensional state of stress i.e., \(\sigma_{1}\), \(\sigma_{2}\), and \(\sigma_{3}\). It is noted that, at the tip of the crack, the confining stress. \(\sigma_{2}\), does not contribute significantly to tensile failure initiation (see Figure 2). Therefore, it is analogous to an extension of [PERSON]'s work. [PERSON]'s original theory deals with the crack initiation and does not consider the crack propagation or shear failure. However, in some cases, tensile failure can propagate parallel to \(\sigma_{1}\) when tensile stress overcomes the tensile strength [69].  
In carbonate rocks, weak zones are considered along the pre-existing cracks, clay lenses, fossils, solution cavities, etc. The brittle-ductile behavior of limestone shows that strength has a negative relationship with textural characteristics [70]. Recrystallization in carbonate rocks under high temperatures significantly affects their stiffness. This process produces the void spaces in carbonates that may start a crack initiation event. Previous studies showed that, in limestone, a crack can easily propagate along the weak zones, such as bedding planes, rather than orthogonal to it [71; 72]. A crack can propagate in a straight path with less energy through a medium having almost the same mechanical characteristics. However, it can bend along the grain boundaries, internal defects, clay lenses, and fossil-matrix interfaces (see Figure 3). During loading, shear failure can be noted along such bends or offsets. Apart from the above discussion, loading direction and strain rate are two important parameters that decisively play a significant role in governing crack propagation. A loading direction parallel to crack propagation helps it to propagate along grain boundaries.  
Figure 2: Crack propagation from a typical [PERSON]’s crack in a 2-dimensional stress field adapted from Hoek and Martin [69].
## 3 Proposed Theory and Design Flow  
As the dumbbell-shaped DGS exhibits the properties of a parallel resonant LC circuit, the equivalent circuit of the DGS with an isolation resistor can be depicted (Figure 5). The figure shows that, after incorporating the isolation resistor, the DGS circuit has three paths, i.e., x, y and z via R, L and C, respectively. Thus, the idea is that at the resonant frequency \(f_{0}\), paths y and z resist the flow of current. Therefore, these paths demonstrate the characteristic of open circuit and the current will follow the alternative path i.e., path x, which has the resistor across it. Hence, the divider attains maximum isolation due to resistance across path x, as the current faces maximum resistance. Thus, in this way, by introducing DGS in the ground plane and installing the isolation resistor across it, rather than directly mounting it on a top plane of the transmission line, improved isolation can be achieved.  
Figure 6a,b shows step-by-step algorithms for the design of the proposed WPD and DGS section, respectively, via flow charts. Although the initial calculated values of parameters will not yield an absolute required result, they pave the way towards obtaining an approximate result. In this way, the variations in the variables of different parameters and their overall effect can be judged and approximated, which leads the way to tune the circuit to achieve the preferable outcome. The steps for the design of the circuit may seem complex and rigorous, but the design flow illustrated in Figure 6a,b can provide an easy and comprehensible way to obtain an acceptable result.  
Figure 5: Dumbbell-shaped DGS section between the transmission lines TL2 with its equivalent lumped elements and physical dimensions.