esa-sceva/satcom-chunk-collection huggingface dataset:
## 5 Conclusions  
A planar railway vehicle with a traction transmission model and the TVMS model of spalling spur gears is established. Then, the influence of the spalling length, width, and depth on TVMS are analyzed, and the most sensitive geometrical dimension is found. Furthermore, the evolution law of dynamic characteristics under the change in tooth spalling length was further explored. Based on the above research, the following conclusions can be obtained:  
1. The spalling length and depth both reduce the TVMS amplitude at the defect location, while the spalling width increases the loss range of TVMS. Overall, the spalling length has the most significant impact on TVMS.  
2. From a comparative perspective, the CF is the best candidate indicator of sensitivity and linearity under the ideal noiseless environment. Unfortunately, the strong noise caused by track irregularities leads to disordered fault evaluation. After simple high-pass filtering,  
Figure 14: The variation of vertical vibration indicators of the first gearbox housing after filtering.  
the adverse effects of vehicle speed and track irregularities can be eliminated on the RMS and VAR. However, the sensitivity of these indicators is poor.  
3. From the time-frequency spectrum, gear tooth spalling cannot exhibit a significant sideband in the operating environment of railway vehicles. This is very different from faults such as root cracks and missing teeth. Therefore, it can be considered a weak signal fault diagnosis and requires effective denoising and weak feature extraction algorithms in fault diagnosis to accurately extract its characteristic frequency.  
Based on the above conclusions, this paper recommends setting a threshold value at a specific speed and applying advanced denoising methods to evaluate gear spalling. This strategy is simple and effective while it avoids the adverse effects that are caused by strong-noise and non-stationary processes.  
Conceptualization, J.W.; methodology, Y.L. and J.W.; software, Y.L. and J.W.; investigation, Y.L.; resources, J.W.; writing--original draft preparation, Y.L.; writing--review and editing, J.L., P.C. and Y.S.; visualization, Y.L.; supervision, J.W. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Natural Science Foundation of China (grant numbers: 52205083, 52272385), the R&D Program of Beijing Municipal Education Commission (KZ202210015019), the Beijing Natural Science Foundation (grant numbers: 3214042, L211008), and the Pyramid Talent Training Project of Beijing University of Civil Engineering and Architecture (grant number: JDYC20220827).  
Not applicable.  
The authors declare no conflict of interest.
# Spectral Envelope Transformation in Singing Voice for Advanced Pitch Shifting
## 5 Evaluation Methodology
### Subjective Evaluation Methodology  
A subjective comparison between our method, PSOLA and the Flex Pitch plugin of Logic Pro X [38] has been carried out. Each selected note was pitch shifted a fifth or an octave above or below the original pitch by using the three different methods mentioned. The system performance was subjectively evaluated by means of a survey open to volunteers on our website ([[https://encuestas.uma.es/73985/lang-en](https://encuestas.uma.es/73985/lang-en)]([https://encuestas.uma.es/73985/lang-en](https://encuestas.uma.es/73985/lang-en))). The participants listened to the different transformations randomly ordered, and they were asked to evaluate the quality of each of them from zero to 100, regarding naturalness, vowel intelligibility and breathiness. The scoring scheme was made based on a continuous quality scale (CQS), following the Recommendation ITU-R BS.1534-3 [39], which divides the range into five equal intervals with the following adjectives, from worst to best: bad, poor, fair, good and excellent (see Figure 10). The participants were inquired about the listening conditions and their musical training knowledge.  
The samples were grouped into two blocks. The first block contained five isolated sung notes and their corresponding three transformations per note. The second block contained three melodies consisting of four notes placed together and their transformations; this setup was prepared so that the participants were able to listen to lengthier samples of transformed musical notes, making it easier to notice the differences between them.
###### Abstract  
A liquid chromatography-negative ion electrospray ionization-tandem mass spectrometry method was developed for the simultaneous analysis of bisphenol A, 4-octylphenol, 4-nonylphenol, diethylslibestrol, 17B-estradiol, estirol, estrone, 17\(\alpha\)-ethinylestradiol, prednisone, and prednisolone. This method used solid-phase extraction with an elution solvent of acetonitrile to improve the stability of the analytes. To maintain the stability of analytes analyses were completed within five days. The recoveries ranged from 84 to 112% and the relative standard deviation of analysis of duplicate samples was \(<\)10%. The limits of quantitation were 1-10 ng/L. Surface water and wastewater were obtained from five wastewater treatment plants in Saskatchewan. Matrix effects were moderate to severe. Using standard addition calibration, all analytes except diethylslibestrol and 17\(\alpha\)-ethinyl estradiol were detected. There was a low frequency of detection of the target analytes in upstream and downstream water, indicating good removal efficiency during the wastewater treatment process. Bisphenol A and 4-nonylphenol were the only analytes detected downstream. Bisphenol A was the most frequently detected in raw wastewater (133 to 403 ng/L). Estriol was detected more often in raw wastewater than estrone or 17\(\beta\)-estradiol. This is the first Canadian study with the detection of prednisone and prednisolone with concentrations at 198-350 ng/L in raw wastewater at 60% of the wastewater treatment plants.  
endocrine-disrupting chemicals; solid-phase extraction wastewater; liquid chromatography-negative ion electrospray-tandem mass spectrometry; matrix effect +
Footnote †: journal: molecules
## 2 Materials and Methods
### Identical Area Detection of Multi-Platform Point Cloud
\begin{array}{ll}\dfrac{\partial L}{\partial x}=\sum_{i=1}^{u}\left[( z_{i}^{2}+y_{i}^{2})x-x_{i}y_{i}y-x_{i}z_{i}z\right]+\lambda x=0\\ \dfrac{\partial L}{\partial y}=\sum_{i=1}^{u}\left[(x_{i}^{2}+z_{i}^{2})y-x_{ i}y_{i}x-y_{i}z_{i}z\right]+\lambda y=0\\ \dfrac{\partial L}{\partial z}=\sum_{i=1}^{u}\left[(y_{i}^{2}+x_{i}^{2})z-x_{ i}z_{i}x-y_{i}z_{i}y\right]+\lambda z=0\\ \dfrac{\partial L}{\partial\lambda}=x^{2}+y^{2}+z^{2}=1\end{array} \right. \tag{10}\]Let:  
\[\mathbf{M}=\sum_{i=1}^{u} \begin{bmatrix}(z_{i}^{2}+y_{i}^{2})&-x_{i}y_{i}&-x_{i}z_{i} \\ -x_{i}y_{i}&(x_{i}^{2}+z_{i}^{2})&-y_{i}z_{i}\\ -x_{i}z_{i}&-y_{i}z_{i}&(y_{i}^{2}+x_{i}^{2})\end{bmatrix} \quad\mathbf{ev}= \begin{pmatrix} x\\ y\\ z\end{pmatrix}  \tag{11}\]  
Equation (9) can be transformed into \(\mathbf{M}\cdot\mathbf{ev}=-\lambda\cdot\mathbf{ev}\), and the standard eigenvectors \(\mathbf{ev}\) of the coefficient matrix \(\mathbf{M}\) are the non-zero solutions of Equation (9). For a three-denomational point cloud, the coefficient matrix \(\mathbf{M}\) has three eigenvectors \(-\mathbf{ev}_{1}\), \(\mathbf{ev}_{2}\), and \(\mathbf{ev}_{3}\). In general, the axis vectors corresponding to the minimum moment of inertia are the eigenvectors \(\mathbf{ev}_{1}\). To extract the identical areas from multi-platform point clouds, it is necessary to analyze the similarity of the axis vectors corresponding to the minimum moment of inertia from the corresponding point cloud. In geometry, the cosine of an angle can be used to measure the difference between the directions of two vectors, which can be expressed as:  
\[\cos\theta_{ev}=\frac{\mathbf{ev}_{1}\cdot\mathbf{ev}_{2}}{|\mathbf{ev}_{1}||\mathbf{ev}_{2}|} \tag{12}\]  
A larger cosine indicates the angle between the two vectors is smaller, i.e., the point cloud distribution of the corresponding grids is more similar. On the contrary, a smaller cosine indicates the angle between the two vectors is larger, and the distribution of the corresponding point cloud is less similar. In our study, the octree index is constructed to search corresponding grids from the multi-platform point cloud. Their minimum moment of inertia is calculated separately for the discrete point cloud after grid division, and then the similarity is analyzed using the cosine between the axis vectors of the corresponding grids to determine the identical areas from the multi-platform point cloud.
## 6 Results  
### Simulation Setup  
A satellite network simulation scenario was developed utilizing Systems Tool Kit (STK) to model an intelligent remote sensing constellation inspired by the Jilin-1 architecture, comprising 300 satellites distributed across 20 distinct solar synchronous orbits. These orbits were configured with a nominal altitude of 656 km and an inclination angle of 98.04\({}^{\circ}\), optimizing coverage for high-latitude regions while maintaining consistent solar illumination patterns. Concurrently, a communication satellite constellation was designed based on the Starlink topology, deploying 650 satellites across 25 Walker orbit planes at an altitude of 550 km with a 53\({}^{\circ}\) inclination angle to ensure the global coverage and low-latency communication capabilities. Both constellations were integrated within the STK environment to evaluate the inter-satellite link performance, coverage patterns, and network resilience under dynamic orbital mechanics. The simulation parameters--including ephemeris data, sensor specifications, and communication protocols--are systematically documented in Table 1, while the hyperparameter configurations governing constellation control algorithms and network optimization routines are presented in Table 2, providing a comprehensive framework for validating system-level performance metrics.
# Data Analysis, Simulation and Visualization for Environmentally Safe Maritime Data
## 1 Introduction
### ICT and Maritime Data Engineering  
The advances of Information and Communication Technology (ICT) could certainly be exploited for both real-time monitoring and alerting functionalities and for exploring patterns of past data behavior and obtaining knowledge about their properties with the forecasting ability into mind. The AIS system, along with other sensor data such as radar and GPS can fully support the above operations.  
External conditions on the sea also play an important role to maritime traffic engineering. Sea and weather conditions are often one of the main causes of marine accidents, also deteriorating any potential rescue plan. In the Mediterranean Sea, on the 8 th of December 1966, _SS Heraklion_ was overwhelmed by heavy seas in the Aegean Sea whilst on passage from Crete to Piraeus and capsized. Of the 281 people on board only 47 survived [2]. A more recent incident (luckily without casualties) happened on the 8 th of February 2016, the vessel _MV Epsilon_, severe weather conditions resulted in its heavy roll during a turn and mass shifting of its cargo, causing damages and some injuries [3]. Some cases from marine accidents in the Artic region are also presented in [4].  
ICT has portrayed significant improvements towards this direction as well, by deploying real-time monitoring or modeling systems that constantly provide software agents with meteorological and sea conditions for a given location. Big data and data mining have also been developed into one of the fastest-growing areas in ICT. The vast amounts of generated data from the marine traffic domain and from other sources as well, requires sophisticated solutions when handling, collecting and analyzing big data to extract meaningful knowledge.  
A large variety of data mining platforms have been introduced, requiring less programming and deploying effort from the user's perspective than ever. Furthermore, web technologies have progressed to a phase that nowadays, one can use any type of electronic device (such as smartphones, tablets, PCs) and gain full access to distributed data, hybrid methods and sophisticated visualization outcomes. Based on all the above arguments, it is mature to state that the proposed work, is utilizing all of the aforementioned ICT services in order to ensure effective modeling, analysis and simulation of marine traffic data and provide experts with useful insight on current but also future trends and patterns.
## 4 Discussion  
Herein, we fabricated a substrate with 86.54% transmittance by mixing PDMS and Ecoflex in an 8:2 weight ratio. After applying various pre-strains (0%, 10%, 30%) to the Ecoflex/PDMS substrate, PDDA (GO) and PVA (MMT) solutions with opposite charges were laminated using the LbL method, a non-vacuum process to form barrier layers with good interlayer bonding via electrostatic attraction. LbL assembly by absorption from the solution is a good approach to the fabrication of near perfectly oriented and aligned nano-material/polymer multilayers. The experimental results confirm that the method of laminating barrier layers after applying pre-strain produced wrinkles. These wrinkles allow strain to be endured on the surface of the barrier layer, preventing cracks during the stretching test and resulting in an improved WVTR. The 30-layer coated Ecoflex/PDMS substrate had a low WVTR rate of 2.5 \(\times\) 10\({}^{-2}\) g/m\({}^{2}\) day after 100 cycles of the stretching test. These studies found that the nano-material/polymer multilayer structure has a strong tendency to be suitable as a stretchable gas barrier film. The PDDA (GO)/PVA (MMT) multilayer coated Eco-flex/PDMS gas barrier film shows great potential for use in stretchable applications. In addition, this simple and fast method can be suitable for stretchable gas barrier fabrication technologies.  
Conceptualization, S.K. and T.K.; methodology, S.K.; software, S.K.; validation, S.K., T.K. and B.-K.J.; formal analysis, S.K.; investigation, S.K.; resources, B.-K.J.; data curation, S.K. and T.K.; writing--original draft preparation, S.K.; writing--review and editing, B.-K.J.; visualization, S.K.; supervision, B.-K.J. and D.K.; project administration, B.-K.J.; funding acquisition, B.-K.J. and D.K. All authors have read and agreed to the published version of the manuscript.  
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No.2018 RIA6A1A030 26005). This work was supported by the Technology Innovation Program (20012463, Development of SEM type Nano 3D Printing technology) funded by the Ministry of Trade, Industry and Energy (MOTIE, Korea).  
Not applicable.  
The authors declare no conflict of interest.
# Collaborative Planning in Non-Hierarchical Networks--An Intelligent Negotiation-Based Framework
## 4 Application Case--Analysis and Results
### Intelligent Planning Approaches  
As presented in the intelligent collaborative planning framework description, the intelligent planning module is intended as a facilitator in the iterative search for better collaborative planning solutions. This module works as feedback mechanism where the optimized outputted solutions of the multicriteria optimization module are analyzed, transformed, and routed back as inputs to the circuit of the collaborative planning negotiation in the next iteration as part of a cause-and-effect loop.  
Since the negotiation process of creating the overall supply chain plan relies on the minimization of the number of requests for quotation (RfQ) for every potential partner, the approach of defining new framings is a critical step.  
Using the four implemented strategies for the intelligent planning module (see Table 1) it was possible to assess the rate of improvement of the multicriteria evaluation of the optimized alternative collaborative plans on each iteration.  
Table 5 presents the intelligent planning module results comparison for each strategy on each iteration using a uniform normalization procedure. The initial values for the temporal frames used in the RfQ were the same for all four approaches, which led to an initial set of results similar for all four strategies after the plan optimization. For the second and subsequent iterations, a new temporal frame was defined for every RfQ according to the applied strategy. Table 5 presents the normalized plan assessment score in each strategy approach through the five iterations.  
By analyzing the application case parameters for each strategy approach, it becomes evident that all four strategies examined in the intelligent planning module yielded noteworthy enhancements throughout the negotiation process. Particularly, in the fifth iteration, the results demonstrated a maximum deviation of less than 5.4% between the worst and best outcomes achieved.  
The best strategy approaches were the \"best proposal\" and \"genetic approach\", where the results differences were less than 1.5% in the multicriteria evaluation score.
# Topology Optimization of an Aerospace Bracket: Numerical and Experimental Investigation
###### Abstract  
The integration of topology optimization into additive manufacturing provides unmatched possibilities for the sustainable manufacturing of lightweight, intricate, custom parts with less material at a lower production time and cost. This study aims to apply and benchmark topology optimization methods, in conjunction with additive manufacturing, to enhance the design of functional components used in aerospace applications, while simultaneously providing an experimental verification and comparative analysis of such optimization techniques. This approach was applied to an industrial bracket used in aerospace applications, which was optimized with the aim of weight reduction without sacrificing its original mechanical stiffness. A density-based technique and a level-set method were used to perform the analysis and optimization, whereas fabrication was performed using fused deposition modeling. Finally, a compression and tensile testing machine was employed for the testing, verification, and comparison of the exhibited mechanical strength for the whole range of printed parts, under the same load conditions. The optimized designs achieved a 20% weight reduction while maintaining the compression displacement of the initial components at the given load. The achieved results demonstrate that topologically optimized components can significantly enhance the design of real-life components, such as those used in the weight-sensitive industrial applications considered in this work.  
additive manufacturing topology optimization; level-set method; density-based method +
Footnote †: journal: Applied Sciences
# Structural Modal Time Domain Identification Method Based on the Bayesian Uncertain Quantification
## 4 Numerical Examples  
### Three Degrees of Freedom Spring-Mass System  
This example identifies the modal parameters of the three degrees of freedom system using displacement response signals simulated by the numerical experiments, as shown in Figure 2. The system has linear time-invariant properties and is assumed to have proportional damping. The system stiffness and quality parameters are as follows: \(k_{1}=300\) N/m, \(k_{2}=50\) N/m, \(k_{3}=100\) N/m, \(k_{4}=200\) N/m, \(m_{1}=0.2\) kg, \(m_{2}=0.1\) kg, and \(m_{3}=0.3\) kg. The natural frequencies of the system were 3.854, 6.238, and 7.340 Hz, and the damping ratios were all assumed to be 1%. A sinusoidal swept acceleration excitation was applied to the system, and the excitation frequency was linearly increased from 0.1 Hz to 15 Hz within 20 s, with an excitation amplitude of 1 m/s\({}^{2}\). The displacement of the three masses was measured with a sampling rate of 100 Hz. The measured responses were simulated by adding independently and identically distributed Gaussian white noise to the theoretical responses.  
Figure 1: Computational flowchart based on the Bayesian time domain identification method.
# SPICE-Aided Compact Electrothermal Model of Impulse Transformers +
## 1 Introduction
A disadvantage of the models described in the cited papers is that they are a very simplified manner of describing thermal properties of transformers. In the paper [7], only one temperature is used to characterize all the transformer components. It is assumed that the core and the windings have the same temperature. In contrast, in the paper [14], different values of the core temperature \(T_{C}\) and temperature of all the windings \(T_{W}\) were used. It is also worth noticing that in the paper [9], some measurements results are shown, which prove that temperatures of transformer windings can visibly differ between each other. Such differences can exceed even 20 \({}^{\circ}\)C for a toroidal transformer. On the other hand, a difference between temperature of primary winding and temperature of the core for the same transformer can exceed even 40 \({}^{\circ}\)C [9]. Temperature distribution on the surface of each of the mentioned parts of a transformer is quasi uniform and differences between measured values of temperature on these parts are smaller than 4 \({}^{\circ}\)C.  
This paper is an extended version of the conference paper [22]. It presents a compact electrothermal model of the impulse transformer. In comparison to the paper [22], the description of the elaborated model is extended and additional measurements and computation results of different transformers are shown and discussed. Particularly, results of investigations of toroidal and planar transformers are presented. An influence of thermal phenomena, frequency, and load resistance on characteristics of the mentioned transformers are investigated. The presented model is formulated as a subcircuit for SPICE. It takes into account the mutual interaction of electrical, magnetic, and thermal phenomena which occur in the transformer. Additionally, differences of the core temperature and temperature of each winding are taken into account in this model. While characterizing thermal phenomena, both the self-heating phenomena in the core and in the windings and mutual thermal couplings between each pair of components of the transformer are taken into account. In the proposed model, the non-linearity of both magnetizing core characteristic and non-linearity of the heat transfer using the thermal model proposed in [9] are taken into account,too. The correctness of the elaborated model is verified experimentally for transformers with different cores and different windings. The form of the elaborated model is described in Section 2. Section 3 describes the investigated transformers. The measurements and computations results are presented and discussed in Section 4.