esa-sceva/satcom-chunk-collection huggingface dataset:
# New Flame Retardant Systems Based on Expanded Graphite for Rigid Polyurethane Foams
## 2 Experimental  
### Materials and Manufacturing  
RPUFs were synthesized from a modified polyisocyanurate rigid foam formulation based on petrochemical components provided by Purinova Sp. z o.o. Izopianol 30/10/C (Purinova Sp. z o.o.) used in the reaction is a fully formulated mixture containing a mixture of polyester polyol (hydroxyl number ca. 230-250 mgKOH/g, the functionality of 2), catalyst (N,N-dimethylcyclohexylamine), flame retardant (Tris(2-chloro-1-methylethyl)phosphate) and chain extender (1,2-propanediol). Purocyn B (Purinova Sp. z o. o.) used in the synthesis is a polymeric diphenylmethane 4, 4\({}^{\prime}\)-diisocyanate (pMDI) containing 31 wt% of free isocyanate groups. The formulations were modified with expanded graphite [EG] S7 treated with sulfuric acid--(generously donated by the S.Z.T.K. 'TAPS'--[PERSON], Poland), fumed silica [SiO\({}_{2}\)] with a specific surface area of 380 m\({}^{2}\)/g (Aerosil 380, Evonic Industries) and ionic liquid [IL], 1-ethyl-3-methylimidazolium tetrafluoroborate [emim] [BF4] (Fluka).  
Four series of foams were made. The first reference series without the addition of a modifier and 3 with modifiers. Both graphite and silica were added based on the weight of the polyol, while the ionic liquid was added based on the weight of the silica. The compositions of RPUFs are presented in Table 1.  
All RPUFs were prepared in a plastic container. An adequate amount of fillers (EG/SiO\({}_{2}\)/IL) were added to the polyol and the mixture (labeled as a component A) was mixed with the stirrer at 800 RPM for 60 s. Then, the isocyanate (labeled as a component B) was added to component A and the formulation was mixed at 2000 RPM for 10 s. The PU mixture was poured into an open mold and allowed to expand freely in the vertical direction. All PU foams were conditioned at room temperature for 24 h. A schematic procedure of synthesis of RPUF is presented in Figure 1.
###### Abstract  
This paper conducts impact dynamics experiments on coal measures sandstone in a deep mine via the established dynamic load and temperature split Hopkinson pressure bar (SHPB) experimental system. Firstly, the experimental conditions for the impact dynamics of fine sandstone were determined, with temperatures of 18, 40, 60, 80, and 100 \({}^{\circ}\)C, an axial static load range of 1-9 MPa, and a preset bullet incidence velocity of 1.0-5.0 m/s. Secondly, based on the analysis of the basic parameters and physical composition, the dynamic stress and strain responses of fine sandstone under different experimental conditions were obtained, and the change mechanism of its dynamic mechanical process was theoretically analyzed. When the temperature rose from 18 \({}^{\circ}\)C to 100 \({}^{\circ}\)C, the dynamic peak stress of fine sandstone increased from 36.04 MPa to 73.41 MPa, with an increase of 103.7%. At a temperature of 40 \({}^{\circ}\)C, when the axial static load increased from 1 MPa to 9 MPa, the dynamic stress peak of fine sandstone increased from 57.25 MPa to 80.01 MPa, and the corresponding peak strain also showed an increasing trend. The experiment analyzed the variation characteristics of dynamic stress in fine sandstone under the combined action of different strain rates or bullet incidence velocities and different temperatures. In the strain rate range of 47.1 s\({}^{-1}\) to 140.9 s\({}^{-1}\), there was a significant strain rate effect on the dynamic peak stress and peak strain of fine sandstone, which increased with the increase of strain rate. The study found a polynomial relationship between the dynamic mechanical parameters of fine sandstone and the impact of experimental parameters, with a coefficient of determination greater than 0.9. A dynamic stress constitutive model for fine sandstone under one-dimensional stress state under dynamic load and temperature action was established, and the model validation and parameter determination of dynamic stress changes in fine sandstone under different temperature conditions were carried out. The research results provide a new experimental method for the static and dynamic mechanical analysis of coal and rock masses under complex geological conditions and can provide a basic reference for the prevention and control of dynamic disasters in deep mining processes.  
Keywords:coal measures fine sandstone; dynamic mechanical parameters; temperature; axial static load; bullet incident velocity; physical characteristic analysis +
Footnote †: journal:
## 3 Results
### Evaluation of ALEXI/DisALEXI ET
Modeled negative bias in TSEB for irrigated crops on highly advective days has been noted in previous studies [17; 43]. To the northwest of RIP is a large expanse of followed land that causes the horizontal advection of hot/dry air across the vineyard, increasing the evaporative demand and causing latent heat fluxes to exceed available energy. These instances lead to large closed estimates of ET (in relation to unclosed) and discrepancies with modeled values as presented in Figure 2. However, when comparing DisALEXI-PT/DisALEXI-PM ET estimates with unclosed values (Figure 3), biases decrease substantially at RIP (from \(-0.92\) to \(0.10\) mm day\({}^{-1}\) on average for DisALEXI-PM and DisALEXI-PT). A similar circumstance is present at VAC, where a large expanse of barren/non-vegetative land (airport) neighbors the orchard, potentially causing the horizontal advection of hot/dry air across the orchard. MBE values are improved at VAC when validating to unclosed ET; however, more datapoints, particularly during high ET days, are required to determine the extent of advective conditions at the site and how closure influences validation efforts. Evaluation between closed and unclosed observations to modeled ET at OLA shows little difference between the two, indicating advective conditions may not be as prevalent at the site, and the modeled positive bias (for both DisALEXI-PT and DisALEXI-PM) is likely due to other factors.
###### Abstract  
Analytic models, complex simulations, and simple models are being used to predict the production performance of hydraulically fractured shale. Analytical models such as decline curve analysis and rate transient analysis are used for a quick evaluation of reservoir performance. However, they have considerable limitations. For instance, decline curve analysis cannot honor the physical phenomena in shale wells that are related to hydraulic fracture, reservoir characteristics, and fluid flow. On the other hand, even though explicit hydraulic fracture modeling is the most comprehensive approach when compared with other traditional techniques, it cannot guarantee to model enough hydraulic fracture effects. Hence, calibration of the model, which commonly is referred to in the oil and gas industry as history matching, becomes a must. However, history matching of an explicit hydraulic fracture model with limited information is time-consuming and cumbersome. Especially history matching of a full field shale gas/oil model with many wells is a daunting task. In this study, we propose a workflow to integrate numerical reservoir simulation and well test analysis. In the workflow, information such as fracture half-length and enhanced effective permeability are obtained from pressure transient analysis and are used to calibrate grid properties in the vicinity of the plane covered by the fracture length and width. Finally, the simulation model is calibrated using pressure and flow rate data, and it is used for the long-term performance prediction of a hydraulic fractured well. The workflow was evaluated by using a synthetic reservoir model whose permeability mimicked that of a shale formation. As a result, the workflow thus enabled the use of coarse grid blocks, which, in turn, reduced the simulation time to just 1.5% of the simulation runtime consumed by a reference fine grid model.  
hydraulic fracture; pressure transient analysis; reservoir simulation; long term prediction 2022
## 3 Materials and Methods  
### Remote Sensing Dataset  
Multiple remote sensing observations were acquired from the Moderate Resolution Imaging Spectroradiometer (MODIS) using sensors from both Aqua and Terra satellites. Satellite data were used in combination with in situ meteorological data (air temperature and radiation) as inputs for the PT-JPL-thermal model. MODIS land products were retrieved from The Earth Observing System Data and Information System (EOSDIS), which is a core capability in National Aeronautics Space Administration (NASA) Earth Science Data Systems Program. All the selected MODIS products (version 5) were acquired at 1 km pixel resolution for the study period between 2003 to 2012. The temporal resolution of the data sets were: (1) daily for land surface temperature (_LST_), land emissivity (\(\varepsilon_{S}\)) and MODIS overpass time from MOD1A1 and MYD1A1, (2) 8-day-composites for land surface temperature (_LST_) from MOD1A2 and MYD1A2, (3) 8-day-composites of leaf area index (_LAI_) and fraction of photo-synthetically active radiation (\(f_{APAR}\)) from MOD15A2, broadband surface albedo (\(\alpha\)) acquired from MCD43B3, and (4) 16-day-composites of normalized difference vegetation index (_NDVI_) retrieved from MOD13A2. To interpolate to daily from 8 and 16 day-composites variables, the same value was used for the entire period.
# Big Data Collection in Large-Scale Wireless Sensor Networks
## 3 Overview of Big Data
### Big Data Generation
#### 3.3.4 Scientific Data  
Scientific data are a particular source of generation of Big Data. In most cases, scientific projects carried out in areas such as astronomy, earth sciences, and projects related to the study of the ocean and its reconstruction via imagery, are projects generating large quantities of data. As an example of the data generated by different scientific projects, 2 MASS (both Micron All-Sky Surveys)  
Figure 11: Taxonomy of Big Data sources.  
generates 10 terabytes, DPOSS (Le Palomar Digital Sky Survey) generates 3 terabytes, GBT (Green Bank Telescope) produces 20 petabytes, GALEX (The Galaxy Evolution Explorer) has 30 terabytes, LSST (Large Synoptic Survey Telescope) has more than 200 petabytes expected, SDSS (Sloan Digital Sky Survey) produces 40 terabytes, SkyMapper Southern Sky Survey has 500 terabytes, Pan STARRS (Panoramic Survey Telescope and Rapid Response System) has more then 40 petabytes planned, and SKA (Square Kilometer Array) has more than 4.6 exabytes expected [68].
# Early Evidence That Soil Dryness Causes Widespread Decline in Grassland Productivity in China
## 1 Introduction
Due to the unique arid-semi-arid environment and distinct vertical zonality, the carbon cycling processes in Chinese grassland ecosystems are very sensitive to climate change and human disturbances [19; 20; 21]. In this study, Chinese grasslands were the study area, and copula functions and Bayesian equations were introduced to explore the conditional probability of GPP decline in Chinese grassland ecosystems when atmospheric drought (high-VPD event) and soil drought (low-SM event) occurred, respectively. We aim to address the following three issues. 1. To analyze the interannual variability of SM and GPP in Chinese grasslands and to explore the mechanisms of SM regulation of GPP in Chinese grassland ecosystems during historical and future periods. 2. To compare the correlation between the effects of SM on ecosystem GPP in different soil layers, and analyze the conditional probability of drought in soils of different soil layers causing a decline in GPP in Chinese grasslands. 3. To calculate the difference between the probability of ecosystem loss due to soil drought minus the probability of ecosystem loss due to atmospheric drought and determine the key moisture constraints controlling GPP in Chinese grasslands.
# Development of a Holographic Waveguide with Thermal Compensation for Augmented Reality Devices
## 1 Introduction
In addition to calculating the parameters of the waveguide itself, the issue of changing the angles of radiation output forming an augmented reality image from a holographic waveguide is of great interest [11; 12]. This may be due to inaccuracy of the waveguide itself (wedge shape, profile shape accuracy, etc. ), as well as a change in the wavelength of the radiation of the LED or laser diode forming the image. In the future, the article will consider the process of developing the structure of a holographic waveguide that provides thermal compensation. Thermal compensation in this paper means compensation for changes in the diffraction angles of radiation at the output of the waveguide compared with the angles at the entrance to the waveguide, which is caused by a change in the dominant wavelength of the laser semiconductor module or LED when the ambient temperature changes or the radiation source is heated. Such radiation sources can be part of an augmented reality device with a display requiring backlight, i.e., LCoS, LCD, or DLP type. Data on such sources cited by the manufacturer show that, for example, for LEDs when the ambient temperature changes or when the diode is heated within \(-\)20 to 80 degrees, there is a shift of the dominant wavelength by 10-20 nm, and for a semiconductor laser diode with a central wavelength of 635 nm, this shift can be 20 nm Since the operation of the diffraction element, or rather the diffraction angles, are directly related to the wavelength, then for some applications this effect must be taken into account. At the same time, it should be noted that the influence of temperatures on radiation sources in the range of 5 to 35 degrees Celsius (for the environment) was considered, the heating of the LEDs during operation was not  
Figure 1: The scheme of radiation propagation in a holographic waveguide. DOE1—input area, DOE2—relay area, DOE3—output area. determined. For such temperatures, the instability of the photomaterial and the glass of the waveguide substrate does not manifest itself; therefore, possible fluctuations are caused only by the instability factor of the dominant wavelength of the radiation source. Such studies were carried out for diffraction gratings recorded in various materials (for example, bichromed gelatin [13], photopolymer [14; 15; 16]) and showed the dependence of changes in the parameters and efficiency of the material under the influence of temperature. A rather interesting task is the study of image formation in a holographic waveguide with diffraction gratings based on photosensitive material like photoresist, which have not yet been fully carried out.
# A Comprehensive Review and Benchmarking of Fairness-Aware Variants of Machine Learning Models
## 2 Fair Editions of Naive Bayes
### Fairness-Aware [PERSON] [5] introduced the N-Naive Bayes (NNB) algorithm, which extends the 2-Naive Bayes classifier [3] by supporting multiple groups rather than a binary distinction. He proposed two probability-balancing routines to adjust \(P(Y|S)\) (the probability of a positive outcome given a sensitive feature): NNB-Parity, which enforces statistical parity, and NNB-DF, which enforces differential fairness--an extension of the group fairness concept that accounts for intersectional groups (subgroups defined by multiple overlapping sensitive attributes). The NNB classifier was evaluated on income and employment classification tasks using US Census data, a widely recognized real-world benchmark dataset. While NNB-Parity maintained higher accuracy, it tended to over-favor non-privileged groups. In contrast, NNB-DF provided stronger fairness guarantees, effectively reducing bias amplification, albeit at the cost of a more significant accuracy decline.
# Experimental Validation of Ellipsoidal Techniques for State Estimation in Marine Applications
## 4 Modeling of Uncertainty
### Quantification of Measurement Uncertainty: Bounded Measurement Noise
Since the time-varying model leads to significantly better bounds on the reconstruction of the uncertainties, we restrict ourselves in the following investigation to the time-varying model according to Figure 4(b),d, where the intersection of the intervals for the compass sensor and the GPS-based heading intervals according to Figure 6 is employed by the ellipsoidal state observer. Velocity measurement intervals result from a direct use of Definition (63), into which, the bounds for the position errors are directly substituted. In view of the fact that the estimate for the GPS accuracy may be biased because of the specific form of the employed Lissajous-shaped trajectory with different elongations in the \(x_{1}\) and  
Figure 5: Interval-based measurement error identification for the heading of both DDboats. (**a**) Constant error bounds for the heading measurement of DDboat A. (**b**) Time-varying error bounds for the heading measurement of DDboat A. (**c**) Constant error bounds for the heading measurement of DDboat B. (**d**) Time-varying error bounds for the heading measurement of DDboat B. \(x_{2}\) coordinates, the boldface values (as the largest entries in both coordinates) serve as the values for parameterizing the uncertainty model of both \(x_{1}\) and \(x_{2}\).
## 2 Materials and Methods  
The goal of the experiments was to measure and analyze the interference structure of the vector sound fields and the pressure field for several variants of the source maneuvering in the waveguide, and to study the influence of the minima of acoustic energy in the acoustic field generated by the source on the noise immunity of the combined reception. The presence of deep minima of acoustic energy levels, which appear when the distance between the sources and the receivers varies, can lead to periodic loss of contact with the source, and in some cases to a complete loss of contact.  
The investigations were carried out on the continental shelf of the Sea of Japan, using a combined receiving system consisting of a sound pressure channel (P) and three orthogonal sound pressure gradient components (XYZ). The receiving system was installed at given points of the experimental area at specified depths, and a low-frequency tonal acoustic source imitating a discrete component in the noise field of a moving source was towed on various tracks at a distance from the receiving system of up to a maximum of 10 km.  
The autonomous receiving system using a combined receiver (CR) was developed and manufactured at the V.I. Il'ichev Pacific Oceanological Institute. It is a device designed to study the structure of sound fields in shallow sea conditions by recording the sound pressure and three orthogonal sound pressure gradient components, as well as to measure the position of the system in space. The creation and collection of information packets from the combined receiver and orientation sensors are realized by an autonomous digital recording unit, with all information being subsequently saved to a SD card. A photo of the CR in a protective enclosure-cage and the hermetic containers of the receiving system are shown in Figure 1.  
Figure 1: Combined receiver outer look.  
The devices for setting the receiving system include: a 40 kg weight, a halyard submerged to a depth of 5 to 10 m from the surface, buoyancy spheres (securing the halyard and cage from vibration due to surface waves), and a flashing beacon.  
An electromagnetic towed oscillator with a static pressure compensation system was used as a tonal acoustic sound source, emitting a frequency of 134 Hz. The compensation system consisted of an air compressor installed on the towing vehicle, and a high-pressure hose connecting the compressor with the internal cavity of the radiator through the tubulure.  
Experimental studies were carried out in two stages at a hydrophysical test site near Cape Schulz, Posiet Bay, in the Sea of Japan in the summer season. In the first stage, the combined receiver was installed in Vityaz Bay, stationary, at a depth of 27 m, with a site sea depth of 37 m. The acoustic source was towed by a yacht at a depth of 20 m and a speed of 3 knots along two routes: to a distance of around 9.5 km from the receiving system, and back to the starting point (Figure 2).
# A Smart and Mechanized Agricultural Application: From Cultivation to Harvest
## 2 Literature Review
The authors claim that the Tabu search method gave the best results in comparisons. In [41], an evolutionary algorithm was used for a complex strategic land-use problem based on the management of a farming system. This study pursued a multi-purpose strategy that fulfilled spatial constraints in the 50-year planning management of the farm. Although the study is comprehensive, the metaheuristic method used and proposed may not be a very high-performing and efficient solution. In [42], a bi-objective optimization model was proposed that minimizes cost and maximizes geographic diversity. In the test of the proposed method, a case was considered that showed new types of relationships in the food logistics chain. Although the proposed mechanism is interesting, the number of parameters it deals with is not complex enough. In [43], the authors introduced a smart-engine-based decision system focusing on the type of crop, time/month of harvest, type of plant required for the crop, type of harvest, and authorized rental budget. According to the results from this system, the best way to rent and share agricultural equipment was provided. The other metaheuristic-based method focused on economic crop planning at the tactical level or agricultural policy planning at the national level [44]. The supposed crop products could be for home consumption, export (cash crops), or to feed milk cows. The proposed method focused on optimal farm reconstructions that met four objectives (maximize profit and balance of soil structure, and minimize the soil nitrogen and human labor), and a set of stringent constraints. In [45], the authors tried to optimize the deployment of their sensor nodes to best monitor potato and wheat crops. In this regard, they proposed a Genetic Algorithm-based method. Other studies based on metaheuristic algorithms have been presented in the literature in the last few years [46; 47; 48]. In summary, many studies have been carried out in the field of smart and sustainable agriculture, which has become a trend in recent years. Some of these studies, along with their characteristics, are summarized in Table 1. This paper focuses on optimal solutions from cultivation to harvesting benefiting from the IoT, autonomous robots, and a metaheuristic approach in three stages.
## 3 Simulation Examples
### Mode Shape Extraction Using Displacement Approximation of Contact Points
#### 3.3.1 Effect from Noisy Disturbance
So, the two proposed signal denoising algorithms, CEEMDAN-NSPCA and CEEMDAN-IWT, are evaluated for their effectiveness in enhancing mode shape extraction using displacement approximation of contact points. Additionally, two denoising algorithms, CEEMDAN-PCA and IWT, are applied as references.