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1

Santos, Augusto, Diogo Rente, Rui Seabra, and José M. F. Moura. "Learning the Causal Structure of Networked Dynamical Systems under Latent Nodes and Structured Noise." Proceedings of the AAAI Conference on Artificial Intelligence 38, no. 13 (March 24, 2024): 14866–74. http://dx.doi.org/10.1609/aaai.v38i13.29406.

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This paper considers learning the hidden causal network of a linear networked dynamical system (NDS) from the time series data at some of its nodes -- partial observability. The dynamics of the NDS are driven by colored noise that generates spurious associations across pairs of nodes, rendering the problem much harder. To address the challenge of noise correlation and partial observability, we assign to each pair of nodes a feature vector computed from the time series data of observed nodes. The feature embedding is engineered to yield structural consistency: there exists an affine hyperplane that consistently partitions the set of features, separating the feature vectors corresponding to connected pairs of nodes from those corresponding to disconnected pairs. The causal inference problem is thus addressed via clustering the designed features. We demonstrate with simple baseline supervised methods the competitive performance of the proposed causal inference mechanism under broad connectivity regimes and noise correlation levels, including a real world network. Further, we devise novel technical guarantees of structural consistency for linear NDS under the considered regime.
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Fors, Ane S., Camilla Brekke, Anthony P. Doulgeris, Torbjørn Eltoft, Angelika H. H. Renner, and Sebastian Gerland. "Late-summer sea ice segmentation with multi-polarisation SAR features in C and X band." Cryosphere 10, no. 1 (February 17, 2016): 401–15. http://dx.doi.org/10.5194/tc-10-401-2016.

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Abstract. In this study, we investigate the potential of sea ice segmentation by C- and X-band multi-polarisation synthetic aperture radar (SAR) features during late summer. Five high-resolution satellite SAR scenes were recorded in the Fram Strait covering iceberg-fast first-year and old sea ice during a week with air temperatures varying around 0 °C. Sea ice thickness, surface roughness and aerial photographs were collected during a helicopter flight at the site. Six polarimetric SAR features were extracted for each of the scenes. The ability of the individual SAR features to discriminate between sea ice types and their temporal consistency were examined. All SAR features were found to add value to sea ice type discrimination. Relative kurtosis, geometric brightness, cross-polarisation ratio and co-polarisation correlation angle were found to be temporally consistent in the investigated period, while co-polarisation ratio and co-polarisation correlation magnitude were found to be temporally inconsistent. An automatic feature-based segmentation algorithm was tested both for a full SAR feature set and for a reduced SAR feature set limited to temporally consistent features. In C band, the algorithm produced a good late-summer sea ice segmentation, separating the scenes into segments that could be associated with different sea ice types in the next step. The X-band performance was slightly poorer. Excluding temporally inconsistent SAR features improved the segmentation in one of the X-band scenes.
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3

Zaytsev, Sergey V. "SYSTEM ANALYSIS IN THE STUDY OF COMPLEX STRUCTURED SYSTEMS." EKONOMIKA I UPRAVLENIE: PROBLEMY, RESHENIYA 10/3, no. 130 (2022): 94–102. http://dx.doi.org/10.36871/ek.up.p.r.2022.10.03.011.

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The concept of a system develops together with all system analysis. But the starting point of defining a system is to compare it with the environment, the outer shell. The environment is a very important concept, covering what is not included in the system, and the system is a finite set of objects isolated from the environment. There are many different connections that form the relationship between the environment and the system. Separating the system from the environment is the primary task of system analysis. The vital activity of the system and the result of solving the problem depend on it. But the fundamental aspect of consistency is very important, which is that the system as a whole does not have the properties of its elements. The main feature of the tasks of system analysis is the optimality of the decisions taken, that is, not just the solution of the problem, but the development of such recommendations that would guarantee the optimality of its solution most fully and in the shortest possible time.
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Dølven, Knut Ola, Juha Vierinen, Roberto Grilli, Jack Triest, and Bénédicte Ferré. "Response time correction of slow-response sensor data by deconvolution of the growth-law equation." Geoscientific Instrumentation, Methods and Data Systems 11, no. 2 (August 11, 2022): 293–306. http://dx.doi.org/10.5194/gi-11-293-2022.

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Abstract. Accurate high-resolution measurements are essential to improve our understanding of environmental processes. Several chemical sensors relying on membrane separation extraction techniques have slow response times due to a dependence on equilibrium partitioning across the membrane separating the measured medium (i.e., a measuring chamber) and the medium of interest (i.e., a solvent). We present a new technique for deconvolving slow-sensor-response signals using statistical inverse theory; applying a weighted linear least-squares estimator with the growth law as a measurement model. The solution is regularized using model sparsity, assuming changes in the measured quantity occur with a certain time step, which can be selected based on domain-specific knowledge or L-curve analysis. The advantage of this method is that it (1) models error propagation, providing an explicit uncertainty estimate of the response-time-corrected signal; (2) enables evaluation of the solution self consistency; and (3) only requires instrument accuracy, response time, and data as input parameters. Functionality of the technique is demonstrated using simulated, laboratory, and field measurements. In the field experiment, the coefficient of determination (R2) of a slow-response methane sensor in comparison with an alternative fast-response sensor significantly improved from 0.18 to 0.91 after signal deconvolution. This shows how the proposed method can open up a considerably wider set of applications for sensors and methods suffering from slow response times due to a reliance on the efficacy of diffusion processes.
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Remsberg, Ellis, Murali Natarajan, and V. Lynn Harvey. "On the consistency of HNO<sub>3</sub> and NO<sub>2</sub> in the Aleutian High region from the Nimbus 7 LIMS Version 6 data set." Atmospheric Measurement Techniques 11, no. 6 (June 21, 2018): 3611–26. http://dx.doi.org/10.5194/amt-11-3611-2018.

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Abstract. This study uses photochemical calculations along kinematic trajectories in conjunction with Limb Infrared Monitor of the Stratosphere (LIMS) observations to examine the changes in HNO3 and NO2 near 30 hPa in the region of the Aleutian High (AH) during the minor warming event of January 1979. An earlier analysis of Version 5 (V5) LIMS data indicated increases in HNO3 without a corresponding decrease in NO2 in that region and a quasi-wave 2 signature in the zonal distribution of HNO3, unlike the wave 1 signal in ozone and other tracers. Version 6 (V6) LIMS also shows an increase of HNO3 in that region, but NO2 is smaller than from V5. The focus here is to convey that V6 HNO3 and NO2 are of good quality, as shown by a re-examination of their mutual changes in the AH region. Photochemical model calculations initialized with LIMS V6 data show increases of about 2 ppbv in HNO3 over 10 days along trajectories terminating in the AH region on 28 January. Those increases are mainly a result of the nighttime heterogeneous conversion of N2O5 on background stratospheric sulfuric acid aerosols. Changes in the composition of the air parcels depend on the extent of exposure to sunlight and, hence, on the dynamically controlled history of the trajectories. Trajectories that begin in low latitudes and traverse to across the North Pole in a short time lead to the low HNO3 in the region separating the anticyclone from the polar vortex, both of which contain higher HNO3. These findings help to explain the observed seasonal evolution and areal extent of both species. V6 HNO3 and NO2 are suitable, within their errors, for the validation of stratospheric chemistry–climate models.
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6

Interlenghi, Gabriela S., Michael E. Reichenheim, Ana M. Segall-Corrêa, Rafael Pérez-Escamilla, Claudia L. Moraes, and Rosana Salles-Costa. "Suitability of the eight-item version of the Brazilian Household Food Insecurity Measurement Scale to identify risk groups: evidence from a nationwide representative sample." Public Health Nutrition 22, no. 5 (December 27, 2018): 776–84. http://dx.doi.org/10.1017/s1368980018003592.

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AbstractObjectiveThe Brazilian Household Food Insecurity Measurement Scale (EBIA) has eight general/adult items applied in all households and six additional items exclusively asked in households with children and/or adolescents (HHCA). Continuing an investigation programme on the adequacy of model-based cut-off points for EBIA, the present study aims to: (i) explore the capacity of properly stratifying HHCA according to food insecurity (FI) severity level by applying only the eight ‘generic’ items; and (ii) compare it against the fourteen-item scale.DesignLatent class factor analysis (LCFA) models were applied to the answers to the eight general/adult items to identify latent groups corresponding to FI levels and optimal group-separating cut-off points. Analyses involved a thorough classification agreement evaluation and were performed at the national level and by macro-regions.SettingData derived from the cross-sectional Brazilian National Household Sample Survey of 2013.ParticipantsA nationally representative sample of 116 543 households.ResultsIn all households and investigated domains, LCFA detected four distinct household food (in)security groups (food security and three levels of severity of FI) and the same set of cut-off points (1/2, 4/5 and 6/7). Misclassification in the aggregate data was 0·66 % in adult-only households and 1·06 % in HHCA. Comparison of the scale reduced to eight items with the ‘original’ fourteen-item scale demonstrated consistency in the classification. In HHCA, the agreement between both classifications was 96·2 %.ConclusionsResults indicate the eight ‘generic’ items in HHCA can be reliably used when it is not possible to apply the fourteen-item scale.
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Fang, Jie, Yu Liu, and Guofeng Liu. "Enhancing body waves in passive seismic reflection exploration: A case study in Inner Mongolia, China." Interpretation 10, no. 2 (April 11, 2022): B13—B24. http://dx.doi.org/10.1190/int-2021-0113.1.

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Among all geophysical exploration methods, seismic exploration is undoubtedly the most important due to its ability to allow depth exploration at high resolutions. Traditionally speaking, the method needs an active seismic source, such as dynamite, to generate energy and perform reflection and refractions. An active source usually means high cost, and it also can be quite difficult to implement when surface conditions are particularly complex. The use of passive seismic for reflection exploration does not require an active seismic source. It has the potential of providing a low-cost alternative technique in some exploration areas. The main issues related to passive-source body-wave exploration include suppressing the surface waves retrieved from sources located at or near the surface, as well as enhancing the body waves from random sources at depth. We address these problems by developing a preprocessing workflow to suppress the surface waves and the other unwanted coherent noise events in the original data without seriously affecting the remaining body waves. We also propose a method for separating surface and body waves based on the signal-to-noise ratio of the frequency-domain signals. Next, we use crosscorrelation to generate virtual shot gathers, just like the active ones, and use conventional seismic data processing steps to generate the final seismic imaging. By analyzing the passive data set collected from Inner Mongolia, we have verified the applicability of the proposed method, and the retrieved final stack section indicates good consistency with an active seismic stack section along the same line. Accordingly, we assert that the application of this data processing method will contribute to the body-wave imaging and the inversion analysis of passive seismic records.
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Raptis, Sotirios, and Dimitris Koutsouris. "2D Fast Vessel Visualization Using a Vessel Wall Mask Guiding Fine Vessel Detection." International Journal of Biomedical Imaging 2010 (2010): 1–20. http://dx.doi.org/10.1155/2010/580518.

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The paper addresses the fine retinal-vessel's detection issue that is faced in diagnostic applications and aims at assisting in better recognizing fine vessel anomalies in 2D. Our innovation relies in separating key visual features vessels exhibit in order to make the diagnosis of eventual retinopathologies easier to detect. This allows focusing on vessel segments which present fine changes detectable at different sampling scales. We advocate that these changes can be addressed as subsequent stages of the same vessel detection procedure. We first carry out an initial estimate of the basic vessel-wall's network, define the main wall-body, and then try to approach the ridges and branches of the vasculature's using fine detection. Fine vessel screening looks into local structural inconsistencies in vessels properties, into noise, or into not expected intensity variations observed inside pre-known vessel-body areas. The vessels are first modelled sufficiently but not precisely by their walls with a tubular model-structure that is the result of an initial segmentation. This provides a chart of likelyVessel Wall Pixels(VWPs) yielding a form of a likelihood vessel map mainly based on gradient filter's intensity and spatial arrangement parameters (e.g., linear consistency). Specific vessel parameters (centerline, width, location, fall-away rate, main orientation) are post-computed by convolving the image with a set of pre-tuned spatial filters calledMatched Filters(MFs). These are easily computed as Gaussian-like 2D forms that use a limited range sub-optimal parameters adjusted to the dominant vessel characteristics obtained by Spatial Grey Level Difference statistics limiting the range of search into vessel widths of 16, 32, and 64 pixels. Sparse pixels are effectively eliminated by applying a limited range Hough Transform (HT) or region growing. Major benefits are limiting the range of parameters, reducing the search-space for post-convolution to only masked regions, representing almost 2% of the 2D volume, good speed versus accuracy/time trade-off. Results show the potentials of our approach in terms of time for detection ROC analysis and accuracy of vessel pixel (VP) detection.
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9

Shirmard, Hodjat, Ehsan Farahbakhsh, Amin Beiranvand Pour, Aidy M. Muslim, R. Dietmar Müller, and Rohitash Chandra. "Integration of Selective Dimensionality Reduction Techniques for Mineral Exploration Using ASTER Satellite Data." Remote Sensing 12, no. 8 (April 16, 2020): 1261. http://dx.doi.org/10.3390/rs12081261.

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There are a significant number of image processing methods that have been developed during the past decades for detecting anomalous areas, such as hydrothermal alteration zones, using satellite images. Among these methods, dimensionality reduction or transformation techniques are known to be a robust type of methods, which are helpful, as they reduce the extent of a study area at the initial stage of mineral exploration. Principal component analysis (PCA), independent component analysis (ICA), and minimum noise fraction (MNF) are the dimensionality reduction techniques known as multivariate statistical methods that convert a set of observed and correlated input variables into uncorrelated or independent components. In this study, these techniques were comprehensively compared and integrated, to show how they could be jointly applied in remote sensing data analysis for mapping hydrothermal alteration zones associated with epithermal Cu–Au deposits in the Toroud-Chahshirin range, Central Iran. These techniques were applied on specific subsets of the advanced spaceborne thermal emission and reflection radiometer (ASTER) spectral bands for mapping gossans and hydrothermal alteration zones, such as argillic, propylitic, and phyllic zones. The fuzzy logic model was used for integrating the most rational thematic layers derived from the transformation techniques, which led to an efficient remote sensing evidential layer for mineral prospectivity mapping. The results showed that ICA was a more robust technique for generating hydrothermal alteration thematic layers, compared to the other dimensionality reduction techniques. The capabilities of this technique in separating source signals from noise led to improved enhancement of geological features, such as specific alteration zones. In this investigation, several previously unmapped prospective zones were detected using the integrated hydrothermal alteration map and most of the known hydrothermal mineral occurrences showed a high prospectivity value. Fieldwork and laboratory analysis were conducted to validate the results and to verify new prospective zones in the study area, which indicated a good consistency with the remote sensing output. This study demonstrated that the integration of remote sensing-based alteration thematic layers derived from the transformation techniques is a reliable and low-cost approach for mineral prospectivity mapping in metallogenic provinces, at the reconnaissance stage of mineral exploration.
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10

Crabbé, Marcel. "Stratification and cut-elimination." Journal of Symbolic Logic 56, no. 1 (March 1991): 213–26. http://dx.doi.org/10.2307/2274915.

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In this paper, we show the normalization of proofs of NF (Quine's New Foundations; see [15]) minus extensionality. This system, called SF (Stratified Foundations) differs in many respects from the associated system of simple type theory. It is written in a first order language and not in a multi-sorted one, and the formulas need not be stratifiable, except in the instances of the comprehension scheme. There is a universal set, but, for a similar reason as in type theory, the paradoxical sets cannot be formed.It is not immediately apparent, however, that SF is essentially richer than type theory. But it follows from Specker's celebrated result (see [16] and [4]) that the stratifiable formula (extensionality → the universe is not well-orderable) is a theorem of SF.It is known (see [11]) that this set theory is consistent, though the consistency of NF is still an open problem.The connections between consistency and cut-elimination are rather loose. Cut-elimination generally implies consistency. But the converse is not true. In the case of set theory, for example, ZF-like systems, though consistent, cannot be freed of cuts because the separation axioms allow the formation of sets from unstratifiable formulas. There are nevertheless interesting partial results obtained when restrictions are imposed on the removable cuts (see [1] and [9]). The systems with stratifiable comprehension are the only known set-theoretic systems that enjoy full cut-elimination.
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11

Stevermer, Catherine A., and Jason C. Gillette. "Kinematic and Kinetic Indicators of Sit-to-Stand." Journal of Applied Biomechanics 32, no. 1 (February 2016): 7–15. http://dx.doi.org/10.1123/jab.2014-0189.

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Variation in the timing indicators separating sit-to-stand (STS) into movement phases complicates both research comparisons and clinical applications. The purpose of this study was to use kinetic reference standards to identify accurate kinematic and kinetic indicators for STS movement analysis such that consistent indicators might be used for STS from varied initial postures. Healthy adults performed STS using 4 foot placements: foot-neutral, foot-back, right-staggered, and left-staggered. Kinetic and kinematic data were collected from force platforms and an 8-camera video system. Initiation, seat-off, vertical posture, and termination were detected with 5% start and 7.5% end thresholds for changes in kinetic and kinematic STS indicators. Timing differences between kinetic and kinematic indicator time points and the reference vertical seated reaction force end point (seatoff) were determined. Kinematic indicators were compared with selected kinetic indicators using timing differences, statistical similarity, and internal consistency measures. Our results suggest that a single force platform system measuring vertical GRF or a simple camera system to evaluate the shoulder marker position and velocity can accurately and consistently detect STS initiation, seat-off, and vertical posture. In addition, these suggested STS indicators for initiation, seat-off, and vertical posture were not dependent upon foot placement.
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12

ASSENZA, L., and G. LONGHI. "COLLECTIVE AND RELATIVE VARIABLES FOR MASSLESS FIELDS." International Journal of Modern Physics A 15, no. 29 (November 20, 2000): 4575–601. http://dx.doi.org/10.1142/s0217751x00001944.

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In this paper, a set of canonical collective and relative variables for a classical relativistic massless field are defined and discussed. The discussion is based on a harmonic analysis on the light-cone in momentum space. It is shown how to avoid a set of consistency constraints which are necessary in the massive case. As a result a canonical separation of the angular momentum in collective and relative parts and a canonical realization of an extended BMS algebra are obtained.
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Ndukwe, Obineche Charles, and Chukwudi Christian Ezuru. "Measurement and Correlation of the Liquid-Liquid Equilibria of Tertiary-Butyl Alcohol – Water – Benzene System at 30°C and 1 Atmosphere Pressure." Saudi Journal of Engineering and Technology 7, no. 8 (September 25, 2022): 485–94. http://dx.doi.org/10.36348/sjet.2022.v07i08.009.

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The Liquid-Liquid equilibria of Tertiary-Butyl Alcohol – Water – Benzene System were measured experimentally at 30°C and 1atm pressure. The experimental binodal curve compositions were obtained using the cloud point method. The compositions of the two equilibrium phases were analysed using Agilent 7820A series Gas Chromatograph. The consistency of the experimental data was determined using the Hand, Othmer-Tobias and Bachman- Brown correlation equations while the plate point was determined using the Treybal’s method. The effectiveness of the solvent in the extraction was determined by calculating the distribution coefficients and separation factors. The experimental tie-line data were correlated with the Universal Quasi-Chemical (UNIQUAC) and Non-Random Two Liquid (NRTL) activity coefficient models. Also, the deviation between the experimental and calculated equilibrium compositions were calculated using the root mean squared deviation equation. The UNIQUAC predicted data gave a closer resemblance to the experimental.
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Özcan, Tülay, and Eda Yıldız. "Sebze Püresi ile Üretilen Yoğurtların Tekstürel ve Duyusal Özelliklerinin Belirlenmesi." Turkish Journal of Agriculture - Food Science and Technology 4, no. 7 (July 15, 2016): 579. http://dx.doi.org/10.24925/turjaf.v4i7.579-587.719.

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In this study, five different set type yogurt with vegetable purees, namely as control (K), yogurt with pumpkin (YBK), yogurt with carrot (YHA), yogurt with green peas (YBE) and yogurt with zucchini (YYK) were produced. The viable cell counts of S. thermophilus and L. delbrueckii subsp. bulgaricus were increased as a result of the ability of dietary fiber to stimulate their growth which is present in yogurt as puree. Vegetable puree addition had a noticeable effect on pH, titratable acidity, whey separation, sensory properties as well as textural attributes such as firmness, cohesiveness, consistency and viscosity index in yogurt. The highest viscosity index, consistency and firmness were observed in yogurt with the carrot puree, while the samples with zucchini presented the less compact structure and textural properties. As a result the present work showed that all the vegetable puree used had a beneficial role to improve textural properties of set type non-fat yogurt and could be used for the development of dairy products with functional ingredients.
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Roach, Lettie A., Samuel M. Dean, and James A. Renwick. "Consistent biases in Antarctic sea ice concentration simulated by climate models." Cryosphere 12, no. 1 (January 29, 2018): 365–83. http://dx.doi.org/10.5194/tc-12-365-2018.

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Abstract. The simulation of Antarctic sea ice in global climate models often does not agree with observations. In this study, we examine the compactness of sea ice, as well as the regional distribution of sea ice concentration, in climate models from the latest Coupled Model Intercomparison Project (CMIP5) and in satellite observations. We find substantial differences in concentration values between different sets of satellite observations, particularly at high concentrations, requiring careful treatment when comparing to models. As a fraction of total sea ice extent, models simulate too much loose, low-concentration sea ice cover throughout the year, and too little compact, high-concentration cover in the summer. In spite of the differences in physics between models, these tendencies are broadly consistent across the population of 40 CMIP5 simulations, a result not previously highlighted. Separating models with and without an explicit lateral melt term, we find that inclusion of lateral melt may account for overestimation of low-concentration cover. Targeted model experiments with a coupled ocean–sea ice model show that choice of constant floe diameter in the lateral melt scheme can also impact representation of loose ice. This suggests that current sea ice thermodynamics contribute to the inadequate simulation of the low-concentration regime in many models.
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16

Nowek, Andrzej. "Medium-Size Polarized Basis Sets Applicability for Interaction Energy Calculations: He2 and Be2 van der Waals Systems." Collection of Czechoslovak Chemical Communications 58, no. 8 (1993): 1739–50. http://dx.doi.org/10.1135/cccc19931739.

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Polarized bases set approach has been applied for preparation of medium-size contracted GTO basis sets starting from various standard energy-optimized and even-tempered isotropic atomic basis sets. Their usefulness for calculation of the SCF interaction energy and its components as well as dispersion energy consistently determined within the dimer basis set were studied for He2 and Be2 systems for intermediate internuclear separations. The results obtained with polarized basis sets indicate their good performance in comparison with property oriented ones.
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Even, William R., and Donald P. Gregory. "Emulsion-Derived Foams Preparation, Properties, and Application." MRS Bulletin 19, no. 4 (April 1994): 29–33. http://dx.doi.org/10.1557/s0883769400039488.

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Porous polymeric foams are well-known materials and have been produced by a wide variety of techniques ranging from leaching soluble fillers through gas-blowing to phase separation. Although these materials are widely used, their structure is often irregular and difficult to control. However, a novel method for producing porous materials with a more regular structure has been developed based on high internal phase emulsions (HIPE). These foams are called emulsion-derived foams and are commercially known as Polyhipe® (Unilever) polymers.If one takes a liquid oil, introduces water and a suitable emulsifier with agitation, a dilute emulsion is produced with small water droplets dispersed within the oil phase, about the consistency of milk. If the amount of the water (i.e., the internal or pore forming) phase is increased, a concentrated emulsion will be formed and the consistency of the mixture changes into a more viscous fluid. As further water is introduced, a limit is reached where the droplets are so prevalent that they approximate a close-packed structure (see cover of this issue); beyond this point the droplets must distort to accommodate any additional internal phase. For a collection of monodispersed spheres this packing limit corresponds to 74% by volume and is the accepted definition of a high internal phase emulsion, i.e., an emulsion with an internal phase greater than 74%.4 The structure of the emulsion is now analogous to soap bubbles, with thin films surrounding and separating the drops. Note also that, compared to “standard” emulsion polymerization, this is the exact reverse or “inverse” of that process. In the standard route, the dispersed oil phase is polymerized to yield a collection of polymeric spheres; with inverse emulsion, the continuous phase is polymerized, yielding a rigid matrix.
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Caudal, Gérard, Emmanuel Dinnat, and Jacqueline Boutin. "Absolute Calibration of Radar Altimeters: Consistency with Electromagnetic Modeling." Journal of Atmospheric and Oceanic Technology 22, no. 6 (June 1, 2005): 771–81. http://dx.doi.org/10.1175/jtech1743.1.

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Abstract Empirical Ku-band altimeter model functions of near-nadir normalized radar cross-sectional σ° are compared to electromagnetic two-scale quasi-specular theory in the context of a standard sea wave spectral model. Three empirical model functions are tested: (i) the modified Chelton and Wentz model (WCM) using data from Geosat, (ii) the Callahan et al. model using data from TOPEX, and (iii) the Freilich and Vanhoff model using data from the Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR). These three models are basically very similar, except that they differ in terms of the level of absolute calibration. The difference between the absolute calibrations of the two extreme models (MCW and Freilich and Vanhoff) is as high as 1.9 dB. Assuming a sea wave spectrum similar to that used by Elfouhaily et al., the two-scale quasi-specular electromagnetic model is run, with a wave separation wavenumber kd adjusted so as to minimize the rms difference between the theoretical σ°(θ) function and the empirical near-nadir model function. The quality of the best-fit solution is not perfect, however, because the shape and absolute level of the function σ°(θ) cannot usually be adjusted simultaneously by the electromagnetic model. Taking the model function used by Freilich and Vanhoff as a reference, an offset is then introduced to the empirical model function, and the residual error is computed as a function of the offset. The overall quality of the fit is shown to be best when a −1.1 dB offset is introduced into the Freilich and Vanhoff model function. To within 0.1 dB, this corresponds to the offset that would be required to match Callahan et al.’s model function. This result is obtained in a context where the effect of the peakedness of the sea surface was assumed negligible. When this effect is introduced, with a peakedness parameter Δ assumed to be independent of wind speed and taken tentatively as Δ = 0.23, as suggested by Chapron et al., the optimal offset is then found to be −0.2 dB, thus indicating that for this example the best consistency with electromagnetic modeling is closer to Freilich and Vanhoff’s calibration. A more refined assessment would require accurate measurements of the parameter Δ involving both magnitude and variability with wind speed. Such accurate measurements are, unfortunately, not available at this time.
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Dai, Qiuyang, and Faxing Lu. "A New Spatial Registration Algorithm of Aerial Moving Platform to Sea Target Tracking." Sensors 23, no. 13 (July 3, 2023): 6112. http://dx.doi.org/10.3390/s23136112.

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Spatial registration is the primary challenge affecting target tracking accuracy, especially for the aerial moving platform and sea target tracking. In this environment, it is important to account for both the errors in sensor observations and the variations in platform attitude. In order to solve the problem of complex types of errors in the tracking of sea targets by aerial moving platforms, a new spatial registration algorithm is proposed. Through separating and analyzing observation data, the influence of sensor observation error and attitude error on observation data is obtained, and a systematic error consistency matrix is established. Based on observation information from multiple platforms, accurate tracking of sea targets can be accomplished without estimating systematic error. In order to verify the effectiveness of the algorithm, we carried out simulation experiments and practical experiments on the lake, which showed that the new algorithm was more efficient than traditional algorithms.
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Pivnenko, Tat'yana, Yuliya Mihaylovna Pozdnyakova, Victoria Kraschenko, Roman Vladimirovich Esipenko, and Evgeny Valerevich Mikheev. "STUDY OF THE QUALITY OF MUSCLE TISSUE OF THE BLACK MACRURUS (GRENADIER) Coryphaenoides acrolepis IN THE PROCESS OF ITS PROCESSING." Fisheries 2022, no. 3 (June 14, 2022): 109–16. http://dx.doi.org/10.37663/0131-6184-2022-3-109-116.

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The research of physico-chemical and organoleptic quality indicators of the black macrurus (grenadier) Coryphae-noides acrolepis caught under industrial conditions in the South Kuril subzone of the Sea of Okhotsk is presented. The analyzed samples included whole and eviscerated specimens of standard quality, as well as individual specimens with the consistency of muscle tissue characterized as «rubber-like». Comparative analysis showed statistically significant similarity of muscle tissue strength indicators before and after heat treatment, protein fraction content, moisture reten-tion capacity, degree of protein denaturation, enzyme activity and a number of other characteristics for standard sam-ples prepared by various methods and differing in size. Samples with a «rubber-like» consistency sharply differed in all the studied parameters except for enzymatic activity. When separating the proteins of black grenadier muscle tissue by electrophoresis was conducted, differences in the species-specific patterns of the compared samples were found. As-sumptions have been made about the causes of the detected changes.
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Ozherelev, D. A., and V. V. Shalay. "Choosing optimal separator design using hierarchy analysis." Omsk Scientific Bulletin. Series Aviation-Rocket and Power Engineering 4, no. 4 (2020): 75–81. http://dx.doi.org/10.25206/2588-0373-2020-4-4-75-81.

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The article describes the possibility of using the «Method of analysis of hierarchies» when choosing the type of separator. These calculation methods are used to determine the vector of priorities and alternatives according to specified criteria, as well as to assess the consistency of expert opinions. The task is set, alternative options and criteria for selecting a separator design are presented. A hierarchical structure is built for various designs of separators. The method of calculation for a variety of indicators that characterize the types of separation equipment is presented. Based on the results presented in accordance with the technical and economic indicators, the optimal design of the separator is determined
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Rahman, Muhammad Syafiq Aiman Abd, Noor Farah Nazirah Norsamsuddin, Nurul Hafizah Muhamad Tajuddin, S. M. Shahrul Nizan Shikh Zahari, and Sofina Tamam. "Effect of Temperature on the Properties of Poly(Vinylpyrrolidone)-Iron Magnetic Nanocomposite for Oil Recovery." Nano Hybrids and Composites 31 (February 2021): 73–80. http://dx.doi.org/10.4028/www.scientific.net/nhc.31.73.

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The poly (vinylpyrrolidone)-iron magnetic nanocomposite (PVP-Fe NCs) recently used for oil recovery since it capable to remove up to 80% of oil. However, the magnetic properties PVP-Fe NCs might not be consistently performed as it has a tendency to having low magnetism depending on their temperature. This study aims to investigate the effect of temperature of PVP-Fe NCs, to see the effectiveness of oil recovery from aqueous environment by using magnetic decantation method. The PVP-iron magnetic was synthesized by three steps using poly (vinylpyrrolidone), FeCl2•4H2O, FeCl3•6H2O and ammonia solution involving mixing and heating, precipitating and separating. The oil removal was tested by mixing the PVP-Fe NCs into an oil-water mixture to let it coat by oil. The oil-water separation was conducted by using a neodymium magnet. The experiments were repeated using the same PVP-materials with different temperatures such as room temperature, 50°C, 80°C and 90°C. The presence of OH-1 group and the magnetic property of each samples was characterized by using FTIR and VSM. The study reveals that the PVP-Fe NCs have highest magnetism at 80°C compared to other temperatures. 80°C seem to be the optimum temperature to perform the good magnetism of PVP-Fe NCs since it reduces its magnetism at 90°C due to its thicker coat. The also showed that PVP-Fe3 are hydrophilic that can assist in oil separation from water. This study demonstrated a significant finding in oil recovery application using PVP-iron magnetic nanocomposites materials.
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Gazda, D., J. Mareš, E. Friedman, and A. Gal. "MULTI-$\bar K$ (HYPER)NUCLEI AND KAON CONDENSATION." International Journal of Modern Physics E 19, no. 12 (December 2010): 2594–99. http://dx.doi.org/10.1142/s0218301310017137.

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We report on recent relativistic mean-field calculations of multi-[Formula: see text] nuclei1,2 which were performed fully and self-consistently across the periodic table. The [Formula: see text] separation energy [Formula: see text] as well as the nuclear and [Formula: see text]-meson densities were found to saturate with the number of antikaons in the nuclear medium. Saturation appears robust against a wide range of variations, including the nuclear model used and the type of boson fields mediating the strong interactions. In addition, we have explored properties of kaonic hypernuclei — strange systems made of nucleons, hyperons and K- mesons. We observed saturation also in these objects. Since the [Formula: see text] separation energy [Formula: see text] does not exceed 200 MeV, multi-[Formula: see text] nuclei lie energetically well above multi-hyperonic nuclei and it is unlikely that kaon condensation could occur in strong-interaction self-bound hadronic matter.
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Yong, Ching Yee, Rubita Sudirman, Nasrul Humaimi Mahmood, and Kim Mey Chew. "Comparison of Human Jogging and Walking Patterns Using Statistical Tabular, Scatter Distribution and Artificial Classifier." Advanced Materials Research 646 (January 2013): 126–33. http://dx.doi.org/10.4028/www.scientific.net/amr.646.126.

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This study investigates and acts as a trial clinical outcome for human motion and behavior analysis in order to investigate human arm movement during jogging and walking. Three methods were proposed to differentiate and separate both of the jogging and walking data set, they are statistical tabular, scatter distribution and artificial classifier recognition. Linear decision boundary and radial basis function kernel (RBF) were proposed to perform the separation works for artificial classifier recognition section. It aims to establish how widespread the movement and motion of arm will bring to effect of human in life. An experiment was set up in a laboratory environment with conjunction of analyzing human motion and its behavior. The instruments demonstrate adequate internal consistency of optimum RBF kernel for jogging and walking pattern classification. RBF used in this study was successfully differentiate and classify the jogging and walking patterns of a human arm movement during performing these activities.
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Ong, Jing Song, J. Hossen, Poh Ping Em, Thangavel Bhuvaneswari, J. Emerson Raja, Min Thu Soe, Nor Hidayati, Gin Chong Lee, and Sajid Abdullah Alam. "AI-Powered Vision Inspection System for Object Classification Application." International Journal of Membrane Science and Technology 10, no. 1 (September 5, 2023): 363–76. http://dx.doi.org/10.15379/ijmst.v10i1.1817.

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Human operators are often susceptible to eye fatigue due to sleep deprivation and excessive workload, which may negatively impact their consistency and efficiency in performing repetitive and challenging inspection tasks. This paper presents the development of an AI-powered vision inspection system for object sorting applications, utilizing a You-Only-Look-Once (YOLO) version 3 pre-trained model based on Deep Convolutional Neural Network's (DCNN) transfer learning technique. Feature extraction for each data point is performed using Darknet53, which subsequently trains the YOLO v3 model. The dataset is partitioned into a training set and test set at a 90:10 ratio. The trained model achieves a mean average precision (mAP) of 99.146%. Enhancing the precision and recall values of the model can be accomplished by increasing the number of dataset instances used for training.
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Giral Martínez, Juan, Jean-Baptiste Fouvry, and Christophe Pichon. "Young stellar cluster dilution near supermassive black holes: the impact of vector resonant relaxation on neighbour separation." Monthly Notices of the Royal Astronomical Society 499, no. 2 (September 7, 2020): 2714–33. http://dx.doi.org/10.1093/mnras/staa2722.

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ABSTRACT We investigate the rate of orbital orientation dilution of young stellar clusters in the vicinity of supermassive black holes. Within the framework of vector resonant relaxation, we predict the time evolution of the two-point correlation function of the stellar orbital plane orientations as a function of their initial angular separation and diversity in orbital parameters (semimajor axis, eccentricity). As expected, the larger the spread in initial orientations and orbital parameters, the more efficient the dilution of a given set of co-eval stars, with a characteristic time-scale set up by the coherence time of the background potential fluctuations. A Markovian prescription that matches numerical simulations allows us to efficiently probe the underlying kinematic properties of the unresolved nucleus when requesting consistency with a given dilution efficiency, imposed by the observed stellar disc within the 1 arcsec of Sgr A*. As a proof of concept, we compute maps of constant dilution times as a function of the semimajor axis cusp index and fraction of intermediate-mass black holes in the old background stellar cluster. This computation suggests that vector resonant relaxation should prove useful in this context since it impacts orientations on time-scales comparable to the stars’ age.
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Agazie, Gabriella, Akash Anumarlapudi, Anne M. Archibald, Paul T. Baker, Bence Bécsy, Laura Blecha, Alexander Bonilla, et al. "The NANOGrav 15 yr Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational-wave Background." Astrophysical Journal Letters 952, no. 2 (August 1, 2023): L37. http://dx.doi.org/10.3847/2041-8213/ace18b.

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Abstract The NANOGrav 15 yr data set shows evidence for the presence of a low-frequency gravitational-wave background (GWB). While many physical processes can source such low-frequency gravitational waves, here we analyze the signal as coming from a population of supermassive black hole (SMBH) binaries distributed throughout the Universe. We show that astrophysically motivated models of SMBH binary populations are able to reproduce both the amplitude and shape of the observed low-frequency gravitational-wave spectrum. While multiple model variations are able to reproduce the GWB spectrum at our current measurement precision, our results highlight the importance of accurately modeling binary evolution for producing realistic GWB spectra. Additionally, while reasonable parameters are able to reproduce the 15 yr observations, the implied GWB amplitude necessitates either a large number of parameters to be at the edges of expected values or a small number of parameters to be notably different from standard expectations. While we are not yet able to definitively establish the origin of the inferred GWB signal, the consistency of the signal with astrophysical expectations offers a tantalizing prospect for confirming that SMBH binaries are able to form, reach subparsec separations, and eventually coalesce. As the significance grows over time, higher-order features of the GWB spectrum will definitively determine the nature of the GWB and allow for novel constraints on SMBH populations.
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Zhao, Qiang, Qizhen Du, Xufei Gong, Xiangyang Li, Liyun Fu, and Yangkang Chen. "Normalized shaping regularization for robust separation of blended data." GEOPHYSICS 84, no. 5 (September 1, 2019): V281—V293. http://dx.doi.org/10.1190/geo2018-0557.1.

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Simultaneous source acquisition has attracted more and more attention from geophysicists because of its cost savings, whereas it also brings some challenges that have never been addressed before. Deblending of simultaneous source data is usually considered as an underdetermined inverse problem, which can be effectively solved with a least-squares (LS) iterative procedure between data consistency ([Formula: see text]-norm) and regularization ([Formula: see text]-norm or [Formula: see text]-norm). However, when it comes to abnormal noise that follows non-Gaussian distribution and possesses high-amplitude features (e.g., erratic noise, swell noise, and power line noise), the [Formula: see text]-norm is a nonrobust statistic that can easily lead to suboptimal deblended results. Although abnormal noise can be attenuated in the common source domain at first, it is still challenging to apply a coherency-based filter due to the sparse receiver or crossline sampling, e.g., that commonly found in ocean bottom node (OBN) acquisition. To address this problem, we have developed a normalized shaping regularization to make the inversion-based deblending approach robust for the separation of blended data when abnormal noise exists. Its robustness comes from the normalized shaping operator defined by the confidence interval of normal distribution, which minimizes the abnormal risk to a normal level to satisfy the assumption of LS shaping regularization. In special cases, the proposed approach will revert to the classic LS shaping regularization once the normalized coefficient is large enough. Experimental results on synthetic and field data indicate that the proposed method can effectively restore the separated records from blended data at essentially the same convergence rate as the LS shaping regularization for the abnormal noise-free scenario, but it can obtain better deblending performance and less energy leakage when abnormal noise exists.
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Atie, Rosalie, Kevin Dunn, and Mehmet Ozalp. "Religiosity, Attitudes on Diversity and Belonging Among Ordinary Australian Muslims." Australian Journal of Islamic Studies 2, no. 1 (April 9, 2017): 1–15. http://dx.doi.org/10.55831/ajis.v2i1.27.

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Islamic incompatibility is a core discourse of fringe political parties, mostly from the right of the political spectrum, who have agitated against religious diversity and also against immigration of Muslims, especially from certain parts of the world. Smaller scale political alliances, against mosque developments, private Islamic schools or halal certification, also draw heavily on this pre-supposition. Despite the preponderance of such despondent commentary, there is surprisingly little by way of empirical analysis of this assumption of incompatibility. This paper draws on a community survey (n:585) and the results show high rates intercultural mixing in workplaces, educational settings and socially, with little evidence for separatism. These Australian Muslims have very positive views about cultural diversity, most perceive there to be consistency between Islam and Australian norms, and they see themselves as Australian. Those with stronger levels of religiosity have even more positive views on diversity and consistency. We offer two explanations, one based on official multiculturalism, and the other on tenets of Islamic thinking on toleration and moderation.
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Zhang, Rui, Xiaolei Song, Sergey Fomel, Mrinal K. Sen, and Sanjay Srinivasan. "Time-lapse seismic data registration and inversion for CO2 sequestration study at Cranfield." GEOPHYSICS 78, no. 6 (November 1, 2013): B329—B338. http://dx.doi.org/10.1190/geo2012-0386.1.

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The time-lapse seismic survey for [Formula: see text] sequestration study at Cranfield can be problematic because of misalignments between time-lapse data sets. Such misalignments can be caused by the seismic data processing workflow and may result in the wrong interpretation of time-lapse seismic amplitude differences. We propose an efficient local-correlation-based warping method of registering the time-lapse poststack data sets, which can align these data sets without changing original amplitudes. Application of our registration method to Cranfield time-lapse data demonstrates its effectiveness in separating time-shift character from seismic amplitude signature. After registration, time-lapse differences show an improved consistency in vertical cross sections and a more localized distribution of difference amplitudes along the horizon, allowing us to apply a high-resolution basis pursuit inversion (BPI) for acoustic impedances. Inversion results show that decreases in acoustic impedances occur mostly at the top of the injection interval, which can be used as an indicator of rock properties to detect a subsurface [Formula: see text] plume.
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Saraev, Ilya A. "On the reduction of the topological classification of gradient-like flows problem to the classification of polar flows I. A. Saraev." Zhurnal Srednevolzhskogo Matematicheskogo Obshchestva 25, no. 2 (June 30, 2023): 62–75. http://dx.doi.org/10.15507/2079-6900.25.202302.62-75.

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In this paper we consider a class G(Mn) of gradient-like flows on connected closed manifolds of dimension n≥4 such that for any flow ft∈G(Mn) stable and unstable invariant manifolds of saddle equilibria do not intersect invariant manifolds of other saddle equilibria. It is known that the ambient manifold of any flow from the class G(Mn) can be splitted into connected summ of the sphere Sn , gft≥0 copies of direct products Sn−1×S1 , and a simply connected manifold which is not homeomorphic to the sphere. The number gft is determined only by the number of nodal equilibria and the number of saddle equilibria such that one of their invariant manifolds has the dimension (n−1) (we call such equilibria trivial saddles). A simply connected manifold which is not homeomorphic to the sphere presents in the splitting if and only if the set of saddle equilibria contains points with unstable manifolds of dimension i∈{2,…,n−2} (we call such equilibria non-trivial saddles). Moreover, the complete topological classification was obtained for flows from the class G(Mn) without non-trivial saddles. In this paper we prove that for any flow ft∈G(Mn) the carrier manifold can be splitted into a connected sum along pairwise disjoint smoothly embedded spheres (separating spheres) that do not contain equilibrium states of the flow ft and transversally intersect its trajectories. The restriction of the flow ft to the complements to these spheres uniquely (up to topological equivalence and numbering) defines a finite set of flows ft1,…,ftl defined on the components of a connected sum. Moreover, for any j∈1,…,l , the set of saddle equilibria of the flow ftj consists either only of trivial saddles or only of of non-trivial ones and then the flow ftj is polar. We introduce the notion of consistent topological equivalence for flows ft1,…ftj and show that flows ft,f′t∈G(Mn) are topologically equivalent if and only if for each of these flows the set of separating spheres exists that defines consistently topologically equivalent flows on the components of the connected sum.
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Kabanov, Alexander N. "Stepan Tikhonovich Chekurda: Front-line Biography of the Legendary Artilleryman." IZVESTIYA VUZOV SEVERO-KAVKAZSKII REGION SOCIAL SCIENCE, no. 1 (205) (April 6, 2020): 39–52. http://dx.doi.org/10.18522/2687-0770-2020-1-39-52.

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The author of the article attempts to reconstruct the front-line biography of guards Lieutenant Colonel S.T. Chekurda in order to restore historical justice in relation to the memorialization of the hero. In order to achieve this goal, it is intended to solve the following research tasks: to summarize and, on the basis of critical analysis, make sense of the information about him available to researchers, relatives, friends and associates of S.T. Chekurda, separating fiction from reality; to examine the circumstances under which the combat officer was awarded the “Soldier” Order of Glory; to put into circulation new documents concerning the combat bi-ography of S.T. Chekurda; consistently light up the hero 's battle path. The author is far from the thought of achieving the goal completely. Many points remain controversial. At the same time, the results of the analysis provided the ground for further study of the glorified officer’s combat destiny.
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SUPARTINI, IDA AYU MADE, I. KOMANG GDE SUKARSA, and I. GUSTI AYU MADE SRINADI. "ANALISIS DISKRIMINAN PADA KLASIFIKASI DESA DI KABUPATEN TABANAN MENGGUNAKAN METODE K-FOLD CROSS VALIDATION." E-Jurnal Matematika 6, no. 2 (May 31, 2017): 106. http://dx.doi.org/10.24843/mtk.2017.v06.i02.p154.

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Tabanan Regency is one of the eight regencies and one municipality in Bali Province. Administratively, it is divided into 10 districs and villages. There are rural areas and urban areas in the regions. Discriminant analysis is a technique related to the separation of objects into different groups that have been set previously. The purpose of this research is to classify villlages in Tabanan Regency into urban or rural groups with discriminant analysis. Linear discriminant analysis assumes that the covariance matrix of the two groups are equals, if the assumption of equality of covariance matrix is violated, quadratic discriminant analysis can be used for classification. This research uses k-fold crosss validation method for calculating the accuracy of quadratic discriminant function where . Quadratic discriminant function is obtained by with the smallest APER value (). All of classification results are stable and consistence.
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KOCHARIAN, ARMEN N., C. YANG, Y. L. CHIANG, and T. Y. CHOU. "EXACT AND SELF-CONSISTENT RESULTS IN ONE-DIMENSIONAL REPULSIVE HUBBARD MODEL." International Journal of Modern Physics B 17, no. 30 (December 10, 2003): 5749–72. http://dx.doi.org/10.1142/s0217979203023380.

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The shortcomings and advantages of the generalized self-consistent field (GSCF) approach, which includes the electron–hole order parameter [Formula: see text] and the average spin s within the one-dimensional repulsive Hubbard model, are analyzed by comparison of the ground state properties with the corresponding Bethe ansatz results in an entire parameter space of interaction strength U/t ≥ 0, magnetic field h ≥ 0 and electron concentration 0 ≤ n ≤ 1. The GSCF spectral characteristics are derived and criteria are found for the stability of incommensurate magnetic phase with the wave number 0 < q < π. The GSCF theory displays a simple relationship for the double occupancy D(+) in terms of n, s and [Formula: see text], where D(+) underestimates electron correlations at weak and intermediate ranges and overestimates correlations at large interaction strengths. Beyond some critical U/t and n≠1 the GSCF D(+) for spatially homogeneous state vanishes, while the exact D for all n at h=0 decreases gradually as U/t increases. At n ≠ 1 the GSCF chemical potential μ(+) overestimates electron correlations everywhere and variation μ(+)versusn displays electron instability toward the phase separation in the vicinity of n=1. Exactly at n=1 the GSCF μ(+)versusU/t always underestimates electron correlation and as U/t → ∞ at h=0 we have μ(+) → 0, while the Bethe ansatz result gives μ → 2t. In the limiting cases U/t → 0 and U/t → ∞ for all h ≥ 0 and 0 ≤ n ≤ 1 the GSCF ground state energy is exact, which is necessary for formulation of converging perturbation procedure about mean field solution in the entire parameter space.
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De Paulo, Ellisson Henrique, Francine Dalapícola Dos Santos, Gabriely Silveira Folli, Márcia Helena Cassago Nascimento, Mariana Kuster Moro, Pedro Henrique Pereira da Cunha, Samantha Ribeiro Campos da Silva, et al. "VARIABLE SELECTION METHODS APPLIED IN HTGC DATA TO DETERMINE PHYSICOCHEMICAL PROPERTIES OF CRUDE OILS." Revista Ifes Ciência 10, no. 1 (March 25, 2024): 01–27. http://dx.doi.org/10.36524/ric.v10i1.2516.

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High-temperature gas chromatography (HTGC) is an analytical technique employed in the petroleum industry for component separation. By incorporating chemometrics, HTGC data can be effectively utilized to predict various properties of crude oil. However, HTGC chromatograms generate a substantial number of variables, some of which may lack pertinent chemical information. Consequently, employing variable selection methods becomes crucial to reduce the number of variables and enhance the predictive capability of calibration models. In this study, the interval partial least squares (iPLS), synergy interval partial least squares (siPLS), and ordered predictors selection (OPS) methods were applied for variable selection to construct linear regression models. The main objective was to investigate the potential of these methods in predicting eight properties of crude oil: American Petroleum Institute (API) gravity, standardized kinematic viscosity at 50 °C (VISp), flash point (FP), Reid vapor pressure (RVP), micro carbon residue (MCR), saturates (SAT), aromatics (ARO), and polar (POL) content. While all variable selection methods yielded satisfactory results, the OPS-PLS regression models consistently exhibited the best performance in estimating these properties, achieving root mean squared error of prediction (RMSEP) values of 1.244 for API, 0.029 for VISp, 15.356 °C for FP, 0.324 kPa for RVP, 0.629 wt% for MCR, 3.691 wt% for SAT, 2.939 wt% for ARO, and 3.374 wt% for POL. Variable selection demonstrated remarkable effectiveness, significantly improving the accuracy of the models, and allowing for the creation of concise models with a focused set of variables.
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Vijey Aanandhi M, Elancheziyan K, Yamini R, Prakash Chand T, Aysha Jadeera K A, and Binoy Varghese Cheriyan. "Method Development and Validation of Fludrocortisone Acetate Tablets by Reverse Phase HPLC Method." International Journal of Research in Pharmaceutical Sciences 11, no. 4 (December 5, 2020): 6826–33. http://dx.doi.org/10.26452/ijrps.v11i4.3652.

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The purpose or intent of this current study was to establish a fast and sensitive HPLC technique for the perseverance of Fludrocortisone acetate and utilizing best frequently used HPLC technique. This method had been validated as per the ICH requirements to assure that the method consistently meets the predetermined specifications and quality attributes.Utilizing filtered and degassed pH 3.0 Phosphate buffer and Acetonitrile in the ratio 90:10 as a Mobile phase-A and pH 3.0 Phosphate buffer and Acetonitrile in the ratio 65:35 as a Mobile phase-B the established RP-HPLC technique was done. The separation was achieved by using Waters, X-Bridge Shield RP18, (150 X 4.6-mm), 3.5-µm column. Run time and Flow rate was set 45minutes and 1.2mL/min. Injection volume 100µL and wavelength was set 240nm.The correlation coefficient square for fludrocortisones acetate and Fludrocortisone Impurity was found to be 0.9991 and 0.99997. The SD and %RSD for Fludrocortisone Impurity was found to be 0.02 and 1.48 represents method precision. Following validated parameters lies within the limit. Hence, the developed method was precise, simple, fast and accurate.
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Sprenger, Matthias, Pilar Llorens, Carles Cayuela, Francesc Gallart, and Jérôme Latron. "Mechanisms of consistently disjunct soil water pools over (pore) space and time." Hydrology and Earth System Sciences 23, no. 6 (June 28, 2019): 2751–62. http://dx.doi.org/10.5194/hess-23-2751-2019.

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Abstract. The storage and release of water in soils is critical for sustaining plant transpiration and groundwater recharge. However, how much subsurface mixing of water occurs, and how much of the water is available for plants or otherwise percolates to streams and the groundwater is not yet understood. Based on stable isotope (2H and 18O) data, some studies have found that water infiltrating into soils can bypass older pore water. However, the mechanisms leading to the separation of water routed to the streams and water held tightly in smaller pores are still unclear. Here, we address the current limitations of the understanding of subsurface mixing and their consequences regarding the application of stable isotopes in ecohydrological studies. We present an extensive data set, for which we sampled the isotopic composition of mobile and bulk soil water in parallel with groundwater at a fortnightly temporal resolution and stream water and rainfall at a much higher resolution in a Mediterranean long-term research catchment, in Vallcebre, Spain. The data reveal that the mobile and tightly bound water of a silty loam soil in a Scots pine forest do not mix well; however, they constitute two disjunct subsurface water pools with little exchange, despite intense rainfall events leading to high soil wetness. We show that the isotopic compartmentalization results from the rewetting of small soil pores by isotopically depleted winter/spring rain. Thus, stable isotopes, and, in turn, water residence times, do not only vary across soil depth, but also across soil pores. Our findings have important implications for stable isotope applications in ecohydrological studies assessing the water uptake by plants or the process realism of hydrological models, as the observed processes are currently rarely implemented in the simulation of water partitioning into evapotranspiration and recharge in the critical zone.
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DIKEMAN, R. DAVID, M. SHIFMAN, and N. G. URALTSEV. "b→s+γ: A QCD-CONSISTENT ANALYSIS OF THE PHOTON ENERGY DISTRIBUTION." International Journal of Modern Physics A 11, no. 03 (January 30, 1996): 571–611. http://dx.doi.org/10.1142/s0217751x96000274.

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The photon energy distribution in the inclusive b→s+γ transitions is a combination of two components: the first component, soft physics, is determined by the so-called primordial distribution function, while the second component, perturbative physics, is governed by hard gluon emission. A simple ansatz is suggested for the primordial distribution function which obeys the QCD constraints known so far. We then discuss in detail how hard gluon emission affects the energy distribution. An extension of the Sudakov approximation is worked out incorporating the Brodsky-Lepage-Mackenzie prescription and its generalizations. We explicitly calculate the marriage of nonperturbative and perturbative effects in the way required by OPE, introducing separation scale µ. A few parameters, such as mb and [Formula: see text] affect the shape of the distribution and, thus, can be determined by matching to the experimental data. The data, still scarce, while not giving precise values for these parameters, yield consistency with theory: the current values of the above parameters lie within experimental uncertainty. On the theoretical side we outline a method allowing one to go beyond the practical version of OPE.
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39

Stephanie, Margareta Vania, Alexander A. Iskandar, and May-On Tjia. "Bonding state energy of metal nanoparticle dimer and its dependence on nanosphere size and interparticle separation." Journal of Nonlinear Optical Physics & Materials 27, no. 02 (June 2018): 1850018. http://dx.doi.org/10.1142/s0218863518500182.

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A study is conducted regarding the effects of particle size [Formula: see text] and interparticle separation [Formula: see text] on the electromagnetic (plasmon) coupling in a dimer of two identical metal nanospheres. The dimer states are modeled as the hybridized bonding and antibonding states of two isolated plasmon states, with the associated energies given in terms of the isolated plasmon energy ([Formula: see text], the coupling energy ([Formula: see text] and the overlap integral ([Formula: see text] of the constituent plasmonic fields. The resonance absorption energies of the isolated plasmon and the dimer in certain dielectric medium are calculated according to the Mie theory for incident light of parallel polarization along the dimer axis. The results are fitted with the bonding state energies of both Au and Ag nanosphere dimers for [Formula: see text] ranging within 10–20[Formula: see text]nm and x varied within [Formula: see text]–200[Formula: see text]nm in compliance with the restricted consideration of dipole absorption spectra. The excellent fits of the bonding state energies [Formula: see text] for the ranges of [Formula: see text] and [Formula: see text] variations are consistently achieved with [Formula: see text] around 0.99 by a single function of the form [Formula: see text] where [Formula: see text] and [Formula: see text] vary with the nanosphere materials and the surrounding media considered. This result suggests the possible relation of the best fitted functional form [Formula: see text] with the underlying physical mechanism.
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Gleason, Christine M., Brenda L. Norcross, and Karen J. Spaleta. "Otolith chemistry discriminates water mass occupancy of Arctic fish in the Chukchi Sea." Marine and Freshwater Research 67, no. 7 (2016): 967. http://dx.doi.org/10.1071/mf15084.

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The microchemistry of otoliths has the potential to reconstruct fish movement patterns and habitat use between environmentally different habitats for individual age classes of Arctic marine fish. Herein, we tested the relationship between the bottom water mass from which a fish was collected and the microchemistry of the most recent growth edge of the fish’s otolith using Mg, Sr, Ba and Ca, and then determined the physical and biological factors that affected the chemical signatures. A discriminant function post hoc analysis of fish occupying bottom water masses resulted in 76% correct classification of Arctic or Polar cod (Boreogadus saida) and 82% correct classification of Arctic staghorn sculpin (Gymnocanthus tricuspis) into bottom water masses of capture when ages were pooled. By separating age classes, correct classifications into water masses of capture were as high as 87% for Arctic cod (three water masses) and 90% for Arctic staghorn sculpin (two water masses). Otolith Ba:Ca, Mg:Ca and Sr:Ca ratios were most consistently affected by bottom water temperature; the latter two were also affected by fish age and fish length. The use of otolith microchemistry to determine occupancy of water masses over time is most promising for Arctic cod, which is widespread and occupies the most thermally diverse habitats in Arctic waters.
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41

Matsumori, Haruka, Kenji Watanabe, Hiroaki Tachiwana, Tomoko Fujita, Yuma Ito, Makio Tokunaga, Kumiko Sakata-Sogawa, et al. "Ribosomal protein L5 facilitates rDNA-bundled condensate and nucleolar assembly." Life Science Alliance 5, no. 7 (March 23, 2022): e202101045. http://dx.doi.org/10.26508/lsa.202101045.

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The nucleolus is the site of ribosome assembly and formed through liquid–liquid phase separation. Multiple ribosomal DNA (rDNA) arrays are bundled in the nucleolus, but the underlying mechanism and significance are unknown. In the present study, we performed high-content screening followed by image profiling with the wndchrm machine learning algorithm. We revealed that cells lacking a specific 60S ribosomal protein set exhibited common nucleolar disintegration. The depletion of RPL5 (also known as uL18), the liquid–liquid phase separation facilitator, was most effective, and resulted in an enlarged and un-separated sub-nucleolar compartment. Single-molecule tracking analysis revealed less-constrained mobility of its components. rDNA arrays were also unbundled. These results were recapitulated by a coarse-grained molecular dynamics model. Transcription and processing of ribosomal RNA were repressed in these aberrant nucleoli. Consistently, the nucleoli were disordered in peripheral blood cells from a Diamond–Blackfan anemia patient harboring a heterozygous, large deletion in RPL5. Our combinatorial analyses newly define the role of RPL5 in rDNA array bundling and the biophysical properties of the nucleolus, which may contribute to the etiology of ribosomopathy.
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42

Hutter, Stephan, Constance Baer, Wencke Walter, Wolfgang Kern, Claudia Haferlach, and Torsten Haferlach. "A Novel Machine Learning Based in silico Pathogenicity Predictor for Missense Variants in a Hematological Setting." Blood 134, Supplement_1 (November 13, 2019): 2090. http://dx.doi.org/10.1182/blood-2019-128488.

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Background: Interpreting the pathogenic potential of an amino-acid changing single nucleotide variant (SNV) in a disease related gene can be challenging, especially for rare variants for which little or no information is available in clinical databases. In silico predictors, tools that predict the functional impact of an SNV algorithmically, can be useful in this scenario, and guidelines for variant interpretation recommend their inclusion in the interpretation process. Resources such as the dbNSFP database, which contains pre-calculated prediction scores for dozens of different algorithms, are readily available today. However, individual predictors rarely come to the same conclusion, and even for well-known disease causing SNVs results can be heterogeneous or even contradictory, which complicates their interpretation. Ensemble predictors such as REVEL, MetaLR/SVM or CADD combine the knowledge/information from multiple individual sources. These predictors use machine learning methods and training sets of pre-defined pathogenic and benign SNVs to integrate individual algorithms into a single, easy to interpret score. However, current training sets are based on pathogenic germline variants, which might cause these predictors to underperform when testing somatic variants. Aim: Development of HePPy (Hematological Predictor of Pathogenicity), an ensemble in silico predictor trained on somatic disease causing variants for use in a hematological setting. Methods: We followed the approach laid out by REVEL and used 10 in silico predictor scores and 4 phylogenetic conservation scores from the dbNSFP data base to train a random forest model. Our training set consisted of 371 unique missense SNVs from 61 hematologically relevant genes that were recurrently identified (in at least 10 patients) during routine diagnostics. All were consistently and unambiguously characterized by hematological experts as either a pathogenic somatic variant (n = 268) or a benign germline variant (n = 103) using a rigorous manual classification process within a data set of 69,879 cases studied between 2005 and 2018. Model accuracy was assessed by 10-fold cross-validation and further evaluated using a test data set consisting of 335 rare missense SNVs from routine diagnostics for which control germline material (buccal swabs, finger nail clippings) from the respective patients was available. Variants originating in the germline were expected to be mainly benign (n = 123), while somatic variants were considered pathogenic (n = 212). We compared the performance of this new tool to REVEL, MetaLR/SVM, CADD and the popular individual predictors SIFT and Polyphen2 by generating receiver operating characteristic (ROC) curves and calculating the area under the curve (AUC). Model implementation and analysis was performed using the R libraries "randomForest", "caret" and "pROC". Results: HePPy scores range from 0 (benign) to 1 (pathogenic) and cross-validation on the training set indicates a high accuracy of 0.968, which is also reflected by the clear separation in the distribution of obtained scores for benign and pathogenic training SNVs (see figure B). Application of the model to the test data set of rare SNVs shows that HePPy (AUC = 0.873) outperforms all other prediction tools in separating germline from somatic variants (see figure A). Surprisingly, both MetaLR (AUC = 0.717) and MetaSVM (AUC = 0.703) performed worse than the individual predictors SIFT (AUC = 0.794) and Polyphen2 (AUC = 0.821), while CADD (AUC = 0.831) and REVEL (AUC = 0.850) showed better performance. HePPy scores for somatic test variants were heavily skewed towards very high values (mean = 0.917). Germline variants had significantly lower scores (mean = 0.466), but their distribution was much more uniform than for somatic variants (see figure C). This suggests, to consider a significant proportion of the rare germline variants to have pathogenic potential. This is in line with the growing awareness of pathogenic germline variants and familial predisposition and emphasizes the importance of in silico predictions and other tools to replace the simple "tumor vs. normal" comparison. Summary: We developed HePPy, a new in silico ensemble predictor that is trained on 371 well-defined hematopathological somatic missense variants, which outperforms other currently available methods for in silico prediction in a hematological setting. Figure Disclosures Hutter: MLL Munich Leukemia Laboratory: Employment. Baer:MLL Munich Leukemia Laboratory: Employment. Walter:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.
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43

Duong, Tin Quoc Chanh, Dau Hieu Duong, and Tan Minh Nguyen. "Identification of magnetic anomalies of adjacent sourses using the wavelet transform modulus maxima and scale normalization." Science and Technology Development Journal - Natural Sciences 1, no. 6 (December 8, 2018): 273–86. http://dx.doi.org/10.32508/stdjns.v1i6.637.

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In the potential field inverse problems, accurate determination of the location for the anomaly sources and their properties played an important role. For geomagnetic anomalies of adjacent sources, they always superimpose upon each other not only in the spatial domain but also in the frequency domain, making the identification of these sources significantly problematic. In this paper, a new mother wavelet for effective analysis the properties of the close potential field sources was used. By theoretical modeling, using the wavelet transform modulus maxima (WTMM) method, we set up a correlative function between the scale parameter and geomagnetic source depth. Moreover, a scale normalization on the wavelet coefficients was introduced to enhancethe resolution for the separation of these sources in the scalograms, thereby determining their depth. After verifying the reliability of the proposed method on the modeling data, we have analysed the geomagnetic data in the Mekong delta. The results of this interpretation were consistency with previously published ones, furthermore, the level of resolution for this technique was quite coincidental with other methods using different geological data.
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44

Najgebauer-Lejko, D., T. Grega, M. Sady, B. Faber, J. Domagała, and B. Machaczka. "Effect of addition of starches of different botanical origin on the yogurt gel properties." Biotehnologija u stocarstvu 23, no. 5-6-2 (2007): 87–94. http://dx.doi.org/10.2298/bah0702087n.

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The aim of the present study was to estimate an effect of addition of different starches (potato, maize, waxy maize and tapioca) on the sensoric properties as well as selected physicochemical properties of set-style yogurts. Sensoric evaluation comprised: color, taste, smell, consistency and general appearance. pH value, titration acidity, degree of syneresis by centrifuge and FIL/IDF methods, content of acetaldehyde and diacetyl were also estimated. All analyses were done on fresh yogurts and after 1 week and 3 weeks of storage at 4?C. It was stated that natural (not supplemented with any starch) yogurt and that fortified with waxy maize starch were characterized with the best sensoric properties. Moreover the latter one was found to maintain the highest acetaldehyde level after 3 weeks of storage. Also maize starch influenced higher level of this aromatic compound. Generally starch additives resulted also in lower acidity of yogurts during the first period of cold storage. Products with maize and tapioca starches demonstrated the highest resistance to whey separation.
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45

Sulman, M. H. M., H. S. Huntley, B. L. Lipphardt, G. Jacobs, P. Hogan, and A. D. Kirwan. "Hyperbolicity in temperature and flow fields during the formation of a Loop Current ring." Nonlinear Processes in Geophysics 20, no. 5 (October 29, 2013): 883–92. http://dx.doi.org/10.5194/npg-20-883-2013.

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Abstract. Loop Current rings (LCRs) are among the largest mesoscale eddies in the world ocean. They arise when bulges formed by the Loop Current in the Gulf of Mexico close off. The LCR formation process may take several weeks, and there may be several separations and reattachments before final separation occurs. It is well established that this period is characterized by a persistent saddle point in the sea surface height field, as seen in both model and satellite data. We present here a detailed study of this saddle region during the formation of Eddy Franklin in 2010, over multiple days and at several depths. Using a data-assimilating Gulf of Mexico implementation of the HYbrid Coordinate Ocean Model (HYCOM), we compare the vertical structure of the currents and temperature fields on 5 and 10 June 2010. Finite-time Lyapunov exponents (FTLE) are computed from the surface down to 200 m to estimate the location of relevant transport barriers. Several new features of the saddle region associated with LCR formation are revealed: the ridges in the FTLE fields are shown to be excellent surrogates for the manifolds delineating the material flow structures with only slight degradation at depth. The intersection of the ridges representing stable and unstable manifolds drops nearly vertically through the water column at both times; remarkably, the material boundary shapes are maintained even as they are advected. Moreover, velocity stagnation points and saddle points in the temperature field are consistently found near the intersections at all depths, and their geographic positions are also nearly constant with depth.
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46

Strus, Oksana, Natalya Polovko, and Yuliya Plaskonis. "THE INVESTIGATION OF THE DEVELOPMENT OF A CREAM COMPOSITION WITH THE SAPROPEL EXTRACT." Asian Journal of Pharmaceutical and Clinical Research 11, no. 7 (July 7, 2018): 147. http://dx.doi.org/10.22159/ajpcr.2018.v11i7.23575.

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Objective: The objective of this research was the development of cream with sapropel extract on the emulsifying base and the investigation of the possibility for cream samples to be in future applied in medicine, cosmetics, and veterinary.Methods: To carry out the research a set of methods (centrifugal, thermal, and potentiometric) to analyze colloidal and thermal stability and determine pH values of the tested samples were used. Organoleptic characteristics of the tested samples and possible signs of physical instability were studied. Rheological properties of the samples were determined on the rotating viscometer. The method of microscopic analysis was carried out to analyze the stability of the emulsion system.Results: The research outcomes revealed that all the prototype samples have thermal and colloid stability, neutral pH value, and consistency that depends on the content of the oil phase and the emulsifying mixture. The samples, containing 15% of Vaseline oil and 4% and 6% of emulsifier no. 1, have low viscosity indexes, and the sample with 10% of emulsifier has a rather dense consistency. The samples containing 20% of oil phase possess unsatisfactory organoleptic properties. Since the sample with 4% of emulsifier possessed low rates of viscosity and phase separation occurred during its storage.Microscopic studies have shown that the sample containing 6% of emulsifier no. 1 exhibits monodisperse and a uniform roundness of drops that indicates the stability of the system.Conclusion: The outcome of the research is the development of the composition of the cream with sapropel extract with the emulsifying base containing 15% of corn oil, 6% of emulsifier no. 1, and 1% of Cetostearyl alcohol and purified water.
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47

Lupenko, Serhii. "The Mathematical Model of Cyclic Signals in Dynamic Systems as a Cyclically Correlated Random Process." Mathematics 10, no. 18 (September 19, 2022): 3406. http://dx.doi.org/10.3390/math10183406.

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This work is devoted to the procedure for constructing of a cyclically correlated random process of a continuous argument as a mathematical model of cyclic signals in dynamic systems, which makes it possible to consistently describe cyclic stochastic signals, both with regular and irregular rhythms, not separating them, but complementing them within the framework of a single integrated model. The class of cyclically correlated random processes includes the subclass of cyclostationary (periodically) correlated random processes, which enable the use of a set of powerful methods of analysis and the forecasting of cyclic signals with a stable rhythm. Mathematical structures that model the cyclic, phase and rhythmic structures of a cyclically correlated random process are presented. The sufficient and necessary conditions that the structural function and the rhythm function of the cyclically correlated random process must satisfy have been established. The advantages of the cyclically correlated random process in comparison with other mathematical models of cyclic signals with a variable rhythm are given. The obtained results contribute to the emergence of a more complete and rigorous theory of this class of random processes and increase the validity of the methods of their analysis and computer simulation.
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48

Zhou, Baofeng, Haiyun Wang, Lili Xie, and Yanru Wang. "Bizarre Waveforms in Strong Motion Records." Shock and Vibration 2015 (2015): 1–17. http://dx.doi.org/10.1155/2015/630362.

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This paper collects a rich set of strong motion records in some typical earthquakes domestic and abroad, checks its seismic events, converts the data format, corrects the zeroline and draws the waveform. Four kinds of abnormal phenomena on the acceleration waveform are revealed, such as spike, asymmetric waveform, obvious baseline drift, and strong motion records packets separation. Then reasonable processing approaches are derived from the preliminary analysis of the generation mechanism for abnormal phenomena. In addition to the effects on time history, Fourier amplitude spectrum and response spectrum are studied before and after strong motion records correction. It is shown that (1) mechanism of spikes is rather complicated; however spikes can be eliminated by “jerk” method, ratio method, and the consistency of the three-component PGA time; (2) mechanism of the asymmetric waveform is of diversity; however, to some extent, the Butterworth low-pass filtering can be applied to correct it; (3) two pieces of strong motion record packets can be connected by searching continuous and repeated data; (4) the method of cumulative adding can be used to find the clear baseline drift; (5) the abnormal waveform directly affects the characteristics of time history and frequency spectrum.
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49

Ravindran, Prabu, and Alex C. Wiedenhoeft. "Caveat emptor: On the Need for Baseline Quality Standards in Computer Vision Wood Identification." Forests 13, no. 4 (April 18, 2022): 632. http://dx.doi.org/10.3390/f13040632.

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Computer vision wood identification (CVWID) has focused on laboratory studies reporting consistently high model accuracies with greatly varying input data quality, data hygiene, and wood identification expertise. Employing examples from published literature, we demonstrate that the highly optimistic model performance in prior works may be attributed to evaluating the wrong functionality—wood specimen identification rather than the desired wood species or genus identification—using limited datasets with data hygiene practices that violate the requirement of clear separation between training and evaluation data. Given the lack of a rigorous framework for a valid methodology and its objective evaluation, we present a set of minimal baseline quality standards for performing and reporting CVWID research and development that can enable valid, objective, and fair evaluation of current and future developments in this rapidly developing field. To elucidate the quality standards, we present a critical revisitation of a prior CVWID study of North American ring-porous woods and an exemplar study incorporating best practices on a new dataset covering the same set of woods. The proposed baseline quality standards can help translate models with high in silico performance to field-operational CVWID systems and allow stakeholders in research, industry, and government to make informed, evidence-based modality-agnostic decisions.
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Feng, Chi, Yuanli Zhu, Anglu Shen, Changpeng Li, Qingjun Song, Bangyi Tao, and Jiangning Zeng. "Assessment of GCOM-C Satellite Imagery in Bloom Detection: A Case Study in the East China Sea." Remote Sensing 15, no. 3 (January 24, 2023): 691. http://dx.doi.org/10.3390/rs15030691.

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The coast of the East China Sea (ECS) is one of the regions most frequently affected by harmful algal blooms in China. Remote sensing monitoring could assist in understanding the mechanism of blooms and their associated environmental changes. Based on imagery from the Second-Generation Global Imager (SGLI) conducted by Global Change Observation Mission-Climate (GCOM-C) (Japan), the accuracy of satellite measurements was initially validated using matched pairs of satellite and ground data relating to the ECS. Additionally, using SGLI data from the coast of the ECS, we compared the applicability of three bloom extraction methods: spectral shape, red tide index, and algal bloom ratio. With an RMSE of less than 25%, satellite data at 490 nm, 565 nm, and 670 nm showed good consistency with locally measured remote sensing reflectance data. However, there was unexpected overestimation at 443 nm of SGLI data. By using a linear correction method, the RMSE at 443 nm was decreased from 27% to 17%. Based on the linear corrected SGLI data, the spectral shape at 490 nm was found to provide the most satisfactory results in separating bloom and non-bloom waters among the three bloom detection methods. In addition, the capability in harmful algae distinguished using SGLI data was discussed. Both of the Bloom Index method and the green-red Spectral Slope method were found to be applicable for phytoplankton classification using SGLI data. Overall, the SGLI data provided by GCOM-C are consistent with local data and can be used to identify bloom water bodies in the ECS, thereby providing new satellite data to support monitoring of bloom changes in the ECS.
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