Miracle-dz/UniFAR-FTUs huggingface dataset:
Structure and Proper Orthogonal Decomposition in Simulations of Wall-Bounded Turbulent Shear Flows with Canonical Geometries

Structural features of canonical wall-bounded turbulent fl ows are described using several techniques, including proper orthogonal decom position (POD). The canonical wall-bounded turbulent flows of channels, pipes, and flat-plate boundary layers include physics important to a wide variety of pra ctical fluid flows with a minimum of geometric complications. Recent studies establ i h the importance of very long motions of streamwise velocity fluctuation, but significant questions remain regarding their forms, how smaller motions may organ ize with respect to these larger motions, and the characteristics of associate d vortical structures. POD extracts highly energetic structures from flow fields and is o ne tool to profitably analyze the direct numerical simulation fields considered i n this study. Since POD modes require significant interpretation, wall-n ormal, onedimensional POD modes for a set of turbulent channel flows are used to establish important features. The modes’ scaling is interpreted in li ght of flow physics, also leading to a method of synthesizing one-dimensional POD mod es. Properties of a pipe flow simulation are then studied via several methods. St atistical quantities, including energy spectra, are used to quantify the very long st reamwise motions and compare with similar experiments. Further properties of en ergy spectra, including their relation to fictitious forces associated with mean Reyn olds stress, are considered in depth. Turbulent structures in the pipe flow are then e xamined in the light of observations from relevant experiments. A variety of metho ds reveal organization patterns of structures in instantaneous fields and their ass ociated vortical structures. POD modes for boundary layer flows are examined. Finally, ver y wide modes that occur when computing POD modes in all three canonical flows ar e compared. The results demonstrate that POD extracts structures relev ant to characterizing wall-bounded turbulent flows. However, significant care is n ecessary in interpreting POD results, and POD modes can be categorized according to th eir self-similarity. i Additional analysis techniques reveal the organization of smaller motions in characteristic patterns to compose very long motions in pipe flow s. These very-largescale motions are observed to contribute large fractions of turbulent kinetic energy and Reynolds stress. The associated vortical structures pos sess characteristics of hairpins, and their organization is considered in light of t he hairpin packet model.
Relative usefulness of stability parameters in assessing adaptability in rice

Twelve rice varieties were grown under 30 environments created through the combination of different dates of seeding, methods of planting, doses of fertilizer and growing seasons. The stability of performance for grain yield of the varieties was assessed using nine different parameters. Variations due to genotypes, environments, and genotype x environment interactions were highly significant and a large portion of these interactions was due to linear regression. Highly significant mean squares were observed for linear as well as nonlinear components. The genotypes were grouped into low, medium and high stability classes for each of the nine parameters and numerically scored on three-point scale. Itwas evident from the computation of total score that the parameters X, b, sd2, and a were adequate in assessing the yield stability of the genotypes. Five varieties, Annapuma, Parijat, Sarathi, Keshari, and IR 36, were the most stable genotypes with high yield potential.
On Kelvin-Voigt model and its generalizations

We consider a generalization of the Kelvin-Voigt model where the elastic part of the Cauchy stress depends non-linearly on the linearized strain and the dissipative part of the Cauchy stress is a nonlinear function of the symmetric part of the velocity gradient. The assumption that the Cauchy stress depends non-linearly on the linearized strain can be justified if one starts with the assumption that the kinematical quantity, the left Cauchy-Green stretch tensor, is a nonlinear function of the Cauchy stress, and linearizes under the assumption that the displacement gradient is small. Long-time and large data existence, uniqueness and regularity properties of weak solution to such a generalized Kelvin-Voigt model are established for the non-homogeneous mixed boundary value problem. The main novelty with regard to the mathematical analysis consists in including nonlinear (non-quadratic) dissipation in the problem.
A numerical study of vortex shedding from a circular cylinder vibrating in the in-line direction

Purpose – The purpose of this paper is to investigate the influence of forced, in-line oscillation of a circular cylinder on an incoming incompressible flow field at different Reynolds numbers. Design/methodology/approach – A space-time finite element approach is employed to model the flow around an oscillating cylinder. Findings – The results show that two (2S), four (2P, two pair) and three vortices (P+S, one pair and one single) are shed in each cycle. In addition, a 2P o mode is also observed, which is similar to the 2P mode but the vortices of the 2P o mode differ in strength. The 2P mode of vortex shedding is observed along the entire wake of the flow field and 2P o mode in the far wake. In some cases, the vortex street is transformed as it travels towards the exit to produce new patterns. One such pattern is observed for the first time in the present work, which is referred to as 2P o * mode. The drag and lift coefficients observed are perfectly periodic at a Reynolds number of 200 and they reach a.
The effect of elliptic shape on the period ratio P1/P2 of emerging coronal loops

Aims. We determine the effect of an elliptical shape on the period ratio for the standing transversal oscillations of a longitudinally stratified coronal loop throughout its emergence from the low solar atmosphere into the ubiquitously magnetised corona. Methods. Under the assumption that elliptical curvature has a negligible effect on eigenfrequencies, the equation that describes the projection of a density profile onto a magnetic flux tube with elliptical shape is obtained in a gravitationally stratified atmosphere. The effect of the elliptical shape on the period ratio of the fundamental mode to the first harmonic (P1/P2) at various stages of emergence is determined, assuming that the oscillation periods are much shorter than the characteristic time scale of loop emergence. Results. We find that there are two separate cases of elliptical shape that occur, the minor ellipse and the major ellipse. It is then shown how the period ratio P1/P2 is dependent upon the ellipticity (� ), the parameter characterising the stage of emergence (λ )a nd the density scale height (H). Ellipticity is found to make an important contribution to P1/P2 for the minor ellipse when compared to its counterpart of standing oscillations of stratified loops with semi-circle or circle-arc shape. The major ellipse was found to have a lesser effect on the period ratio of standing oscillations. We also find the value of P1/P2 is dependent upon the stage of emergence of the loop, where the greatest contribution from emergence to the ratio of P1/P2 is when the loop is almost fully emerged. The important implication for magneto-seismological interpretations of the observations of oscillating coronal loops is that measurements of ellipticity and stage of emergence should supplement observations of oscillation periods and should be considered when applying observed frequencies of the fundamental mode and first harmonic to determine the diagnostic properties of these oscillating loops, e.g. the density scale height or strength of magnetic field. Neglecting the determination of ellipticity and stage of emergence may result in a 35% error in estimating density scale height.
Morphologies and properties of lignocellulose fiber extracted from Typha leaves with potential for composite applications

Abstract Chemical extraction of lignocellulosic fibers from plant leaves requires the control of process factors so that the cellulosic structure of the fibers is not destroyed, and the resulting fibers are extracted with desirable physical properties. Studies have shown that extraction treatment at high temperatures leads to the greater penetration of chemicals and better separation of fibers from non-cellulosic substances in the plant structure. In this study, fiber extraction from Typha leaves at 120 °C with sodium hydroxide during 30–90 min was studied, and the structure of the obtained fiber was investigated using Fourier transforms infrared (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA), scanning electron microscopy (SEM), EDS density mapping, and tensile tests. Also, to evaluate the applicability of the resulting fibers in composites, the pull-out test was used. The results showed the possibility of extracting fiber with suitable properties at a low alkali concentration and a short duration at this temperature.
Exact likelihood inference for two exponential populations based on a joint generalized Type-I hybrid censored sample

Following the work of Chen and Bhattacharyya [Exact confidence bounds for an exponential parameter under hybrid censoring. Comm Statist Theory Methods. 1988;17:1857–1870], several results have been developed regarding the exact likelihood inference of exponential parameters based on different forms of censored samples. In this paper, the conditional maximum likelihood estimators (MLEs) of two exponential mean parameters are derived under joint generalized Type-I hybrid censoring on the two samples. The moment generating functions (MGFs) and the exact densities of the conditional MLEs are obtained, using which exact confidence intervals are then developed for the model parameters. We also derive the means, variances, and mean squared errors of these estimates. An efficient computational method is developed based on the joint MGF. Finally, an example is presented to illustrate the methods of inference developed here.
Human-Centric Digital Twins in Industry: A Comprehensive Review of Enabling Technologies and Implementation Strategies

The last decade saw the emergence of highly autonomous, flexible, re-configurable Cyber-Physical Systems. Research in this domain has been enhanced by the use of high-fidelity simulations, including Digital Twins, which are virtual representations connected to real assets. Digital Twins have been used for process supervision, prediction, or interaction with physical assets. Interaction with Digital Twins is enhanced by Virtual Reality and Augmented Reality, and Industry 5.0-focused research is evolving with the involvement of the human aspect in Digital Twins. This paper aims to review recent research on Human-Centric Digital Twins (HCDTs) and their enabling technologies. A systematic literature review is performed using the VOSviewer keyword mapping technique. Current technologies such as motion sensors, biological sensors, computational intelligence, simulation, and visualization tools are studied for the development of HCDTs in promising application areas. Domain-specific frameworks and guidelines are formed for different HCDT applications that highlight the workflow and desired outcomes, such as the training of AI models, the optimization of ergonomics, the security policy, task allocation, etc. A guideline and comparative analysis for the effective development of HCDTs are created based on the criteria of Machine Learning requirements, sensors, interfaces, and Human Digital Twin inputs.
Variational Data Assimilation with an Adiabatic Version of the NMC Spectral Model

Abstract Variational four-dimensional (4D) data assimilation is performed using an adiabatic version of the National Meteorological Center (NMC) baroclinic spectral primitive equation model with operationally analyzed fields as well as simulated datasets. Two limited-memory quasi-Newton minimization techniques were used to iteratively find the minimum of a cost function, with the NMC forecast as a constraint. The cost function consists of a weighted square sum of the differences between the model forecast and observations over a time interval. In all the experiments described in this paper, observations are available for all degrees of freedom of the model. The derivation of the adjoint of the discretized adiabatic NMC spectral model is presented. The creation of this adjoint model allows the gradient of the cost function with respect to the initial conditions to be computed using a single backward-in-time integration of the adjoint equations. As an initial evaluation of the variational data-assimilation .
The Effect of Silencing the Genes Responsible for the Level of Sphingosine-1-phosphate on the Apoptosis of Colon Cancer Cells

Sphingosine-1-phosphate (S1P) and ceramides (Cer) are engaged in key events of signal transduction, but their involvement in the pathogenesis of colorectal cancer is not conclusive. The aim of our study was to investigate how the modulation of sphingolipid metabolism through the silencing of the genes involved in the formation (SPHK1) and degradation (SGPL1) of sphingosine-1-phosphate would affect the sphingolipid profile and apoptosis of HCT-116 human colorectal cancer cells. Silencing of SPHK1 expression decreased S1P content in HCT-116 cells, which was accompanied by an elevation in sphingosine, C18:0-Cer, and C18:1-Cer, increase in the expression and activation of Caspase-3 and -9, and augmentation of apoptosis. Interestingly, silencing of SGLP1 expression increased cellular content of both the S1P and Cer (C16:0-; C18:0-; C18:1-; C20:0-; and C22:0-Cer), yet inhibited activation of Caspase-3 and upregulated protein expression of Cathepsin-D. The above findings suggest that modulation of the S1P level and S1P/Cer ratio regulates both cellular apoptosis and CRC metastasis through Cathepsin-D modulation. The cellular ratio of S1P/Cer seems to be a crucial component of the above mechanism.
Experimental evidence for a short-wave global mode in film flow along periodic corrugations

Abstract The primary instability of liquid film flow along periodically corrugated substrates is studied experimentally. Two different wall shapes, of the same wavelength and height, are tested for a wide range of inclinations. It is found that, beyond a specific inclination, a new instability mode occurs before the classical, convective, long-wave one. This is a short, travelling wave, which is highly regular and persistently two-dimensional, and appears to be a global mode. The exact shape of the corrugations has a leading-order effect on the inclination at which the new mode appears and on its wavelength at inception. Compared with the behaviour of film flow on a flat substrate, the presently tested periodic walls are found to delay very significantly, but each one to a different extent, the onset of the primary instability. This delay increases with inclination, and presents a distinct discontinuity when transition from the long- to the short-wave mode takes place.
Electrical reorientation of liquid crystal molecules inside cylindrical pores for photonic device applications

We present the simulated distribution of the local director of a nematic liquid crystal inside cylindrical macropores under the influence of an electric field. The Frank free energy approach is used to describe the nematic behavior. The influence of both molecular anchoring strength and pore radius is investigated. The results of this analysis are applied for simulation of an electrically tunable microcavity based on porous silicon infiltrated with a liquid crystal. The Bruggeman approximation is used while calculating the effective refractive index of each layer in the porous silicon multilayer structure. The reflectivity spectrum of the latter is simulated using the transfer matrix approach. The electrical tuning range of a microcavity designed for near-infrared waves is found to vary from 10.5 up to 23 nm for weak and strong surface anchoring conditions, respectively.
Results from the LCLS X-Band Transverse Deflector with Femtosecond Temporal Resolution

An X-band RF transverse deflector composed of two 1-mlong X-band deflecting structures has been recently commissioned at the Linac Coherent Light Source (LCLS) at SLAC National Accelerator Laboratory. Located downstream of the FEL undulator, this device provides electron beam longitudinal phase space diagnostics in both time and energy which enables reconstruction of the X-ray FEL power profiles with an unprecedented resolution. This talk reports on the progress of this new LCLS X-band transverse deflector, first usage experience and measured results.
Groups in which every Finitely Generated Subgroup is almost a Free Factor

In [5] M. Hall Jr. proved, without stating it explicitly, that every finitely generated subgroup of a free group is a free factor of a subgroup of finite index. This result was made explicit, and used to give simpler proofs of known results, in [1] and [7]. The standard generalization to free products was given in [2]: If, following [13], we call a group in which every finitely generated subgroup is a free factor of a subgroup of finite index an M. Hall group, then a free product of M. Hall groups is again an M. Hall group. The recent appearance of [13], in which this result is reproved, and the rather restrictive nature of the property of being an M. Hall group, led us to attempt to determine the structure of such groups. In this paper we go a considerable way towards achieving this for those M. Hall groups which are both finitely generated and accessible.
Analytical image reconstruction of cone-beam projections from limited-angle Compton camera data

Since the integration of gamma-rays on a cone is measured with Compton cameras, some sort of image reconstruction method is necessary. Parra (2000) developed an analytical reconstruction algorithm based on a spherical-harmonics expansion of projection data that covers the entire scattering-angle range. The scattering-angle range is limited due to the electrical noise of the detector and due to the finite detector configuration. In this article, a reconstruction algorithm from the projection of a limited scattering-angle range is presented. The algorithm is based on an inversion of the summed back-projection. The variance of the reconstructed image of a uniform source was analyzed and is proportional to the third power of the number of expansion terms. Thus, window functions are introduced to suppress noise at the cost of spatial resolution. The dependency of the spatial resolution on the number of expansion terms was analyzed. The dependency of the variance on the spatial resolution was found to be variance /spl prop/ (spatial resolution)/sup -1/3/.
Dengue Exposure and Wolbachia wMel Strain Affects the Fertility of Quiescent Eggs of Aedes aegypti

(1) Background: The deployment of the bacterium Wolbachia to reduce arbovirus transmission is ongoing in several countries worldwide. When Wolbachia-carrying Aedes aegypti are released and established in the field, females may feed on dengue-infected hosts. The effects of simultaneous exposure on life-history traits of Ae. aegypti to Wolbachia wMel strain and dengue-1 virus DENV-1 remain unclear. (2) Methods: We monitored 4 groups (mosquitoes with either DENV-1 or Wolbachia, coinfected with DENV-1 and Wolbachia, as well as negative controls) to estimate Ae. aegypti survival, oviposition success, fecundity, collapsing and fertility of quiescent eggs for 12 weeks. (3) Results: Neither DENV-1 nor Wolbachia had a significant impact on mosquito survival nor on mosquito fecundity, although the last parameter showed a tendency to decrease with ageing. There was a significant decrease in oviposition success in individuals carrying Wolbachia. Wolbachia infection and storage time significantly increased egg collapse parameter on the egg viability assay, while DENV-1 had a slight protective effect on the first four weeks of storage. (4) Conclusions: Despite limitations, our results contribute to better understanding of the tripartite interaction of virus, bacteria and mosquito that may take place in field conditions and aid in guaranteeing the Wolbachia strategy success.
The Effects of 12-Week Dual-Task Physical–Cognitive Training on Gait, Balance, Lower Extremity Muscle Strength, and Cognition in Older Adult Women: A Randomized Study

This study aims to investigate the effects of dual-task physical–cognitive the training on body balance (BB), gait performance (GP), lower limb muscle strength (LEMS), and cognitive performance (CP) in a group of cognitively normal older adult women (n = 44; 66.20 ± 4.05 years). Of these, 22 were randomly allocated to the dual-task training (DT) group, and 22 participated in the control group (CG). Assessments were performed at baseline, after 12 weeks of intervention, and at the end of 12 weeks of follow-up, using the following instruments: Timed Up & Go (TUG), Timed Up & Go manual (TUGm), Timed Up & Go cognitive (TUGc), Balance Test (TEC), sit-to-stand test (STS), and verbal fluency test (VF). After 12 weeks of DT training, participants showed a significant time × group interaction in all motor assessments (BB, GP, LEMS), as well as in three cognitive tests (VF-grouping, VF-exchange, VF-total). No time–group interaction effect was indicated for the VF-category test. At all evaluation times, CG members maintained constant physical and cognitive performance. We conclude that 12 weeks of physical–cognitive DT training was effective in promoting BB, GP, and LEMS, as well as CP in cognitively normal older adult women, with lasting effects up to 12 weeks after the intervention.
Photogrammetric Velocities for the Great Bend, Kansas, Tornado of 30 August 1974: Accelerations and Asymmetries

Abstract Late in the afternoon of 30 August 1974 a dozen tornadoes were observed over open farming terrain within a 65 km radius of Great Bend, Kans. All but one of the tornadoes traveled mainly toward the southeast; the other tornado moved northeastward and produced damage near Galatia. One of the largest tornadoes occurred about 40 km west–southwest of Great Bend, and high-resolution motion picture films were taken by a news photographer 2.7 km north of the vortex. The vortex was visible as a rotating column of dense dust and small debris particles. Photogrammetric analysis and tracking of debris in the rotating dust column yield velocities as high as 85 m s−1. Maximum measured horizontal wind speeds are 75 m s−1at z≈90 m AGL and maximum rising motions are 60 m s−1at z≈80 m A remarkable dark band of dust, about 35 m high, apparently outlined a major inflow jet of air accelerating into the vortex at low levels from the west-southwest. The dust band has appeared in other tornado photograph (e.g., Kessler,.
The Effect of Imperfect Contact on the Homogenization of a Micro-periodic Helix

Under study are the equations governing the elastodynamics of a micro-periodic helix, i.e. a helix made of a sequence of unit cells, each containing a thin imperfect interphase embedded within a finite number of other phases. An averaged equation of motion, along with its effective constitutive coefficients, is determined via an asymptotic homogenization method. The results are valid in the case of wavelengths much longer than the length of the unit cell. Formulae for shorter wavelengths can be derived by admitting higher order terms in the expansion.