Miracle-dz/UniFAR-FTUs huggingface dataset:
Vibration analysis of beams with non‐local foundations using the finite element method

In this paper, a non‐local viscoelastic foundation model is proposed and used to analyse the dynamics of beams with different boundary conditions using the finite element method. Unlike local foundation models the reaction of the non‐local model is obtained as a weighted average of state variables over a spatial domain via convolution integrals with spatial kernel functions that depend on a distance measure. In the finite element analysis, the interpolating shape functions of the element displacement field are identical to those of standard two‐node beam elements. However, for non‐local elasticity or damping, nodes remote from the element do have an effect on the energy expressions, and hence the damping and stiffness matrices. The expressions of these direct and cross‐matrices for stiffness and damping may be obtained explicitly for some common spatial kernel functions. Alternatively numerical integration may be applied to obtain solutions. Numerical results for eigenvalues and associated eigenmodes of Euler–Bernoulli beams are presented and compared (where possible) with results in literature using exact solutions and Galerkin approximations. The examples demonstrate that the finite element technique is efficient for the dynamic analysis of beams with non‐local viscoelastic foundations. Copyright © 2007 John Wiley & Sons, Ltd.
Properties of thermal radiation in photonic crystals

We analyze the properties of the thermal radiation in photonic crystals and show that the spectral energy density, the spectral intensity, and the spectral hemispherical power are only limited by the total number of photonic states available. Due to the possible presence of photonic band gaps and the associated spectral redistribution of photonic states, it is possible to have spectral regions over which the thermal radiation generation and propagation are completely inhibited or strongly enhanced relative to the corresponding free space or homogeneous dielectric medium blackbody limits. Using a differential geometry approach, we also investigate the directional properties of the thermal radiation propagation in photonic crystals and analyze the thermal photon focusing effects that take place in these systems.
Correlation of Mid-Trimester Spot Urinary Albumin: Creatinine Ratio With the Adverse Pregnancy Outcome

Background Urinary albumin creatinine ratio (ACR) is a known method of measurement of microalbuminuria. Microalbuminuria may be an early marker of endothelial dysfunction which can lead to various complications during the course of pregnancy. The objective of our study was to evaluate the correlation of mid-trimester spot urinary ACR with the pregnancy outcome. Material and methods We performed a prospective cohort study in the department of Obstetrics & Gynaecology, All India Institute of Medical Sciences, Bhopal, for a period of one year. We studied 130 antenatal women between 14 and 28 weeks of gestation after obtaining written informed consent. The patients with ongoing urinary tract infection (UTI), pre-existing hypertension, or diabetes were excluded. Urinary samples were examined for spot ACR, and the women were followed until delivery. Primary maternal outcomes were development of gestational hypertension, pre-eclampsia, gestational diabetes mellitus (GDM), and preterm labour. Neonatal outcome was assessed in terms of birth weight, the APGAR (Appearance, Pulse, Grimace, Activity, Respiration) scores, and neonatal intensive care unit (NICU) admission. Results In our study, mean urinary ACR was 19.07±12.94 mcg/mg and median urinary ACR (IQR) was 18 (9.43-25.25) mcg/mg. Prevalence of microalbuminuria in our study was 19.2%. It was observed that urinary ACR level was significantly higher in women with maternal complications like GDM, gestational hypertension, preeclampsia, and preterm labour. Also, mean urinary ACR of women who developed preeclampsia was higher (37.53±31.85) compared to women who developed gestational hypertension (27.40±9.71). Urinary ACR level was significantly higher in babies with low APGAR scores and in babies who needed NICU admission (p value < 0.05). The sensitivity and specificity of spot urinary ACR to predict GDM and preeclampsia were found to be good as calculated from the receiver operating curve. Conclusion We found definite correlation of higher values of mid-trimester urinary ACR with the adverse pregnancy outcome.
Stochastic differential inclusions

Stochastic differential inclusions (SDIs) on R have been investigated in this thesis, dx(t) ∈ a(t, x(t))dt + d1 ∑ j=1 b(t, x(t))dw t , where a is a maximal monotone mapping, b is a Lipschitz continuous function, and w is a Wiener process. The principal aim of this work is to present some new results on solvability and approximations of SDIs. Two methods are adapted to obtain our results: the method of minimization and the method of implicit approximation. We interpret the method of monotonicity as a method of constructing minimizers to certain convex functions. Under the monotonicity condition and the usual linear growth condition, the solutions are characterized as the minimizers of convex functionals, and are constructed via implicit approximations. Implicit numerical scheme is given and the result on the rate of convergence is also presented. The ideas of our work are inspired by N.V. Krylov, where stochastic differential equations (SDEs) in R are solved by minimizing convex functions via Euler approximations. Furthermore, since the linear growth condition is too strong, an approach is proposed for truncating maximal monotone functions to get bounded maximal monotone functions. It is a technical challenge in this thesis. Thus the existence of solutions to SDIs is proved under essentially weaker growth condition than the linear growth. For a special case of SDEs, a few of recent results from [5] are generalized. Some existing results of the convergence by implicit numerical schemes are proved under the locally Lipschitz condition. We will show that under certain weaker conditions, if the drift coefficient satisfies one-sided Lipschitz condition and the diffusion coefficient is Lipschitz continuous, implicit approximations applied to SDEs, converge almost surely to the solution of SDEs. The rate of convergence we get is 1/4. Finally it is shown that SDEs can directly be associated to mini-max problems. It is demonstrated that there exists strong solutions which are ‘saddle points’ of mini-max problems. This technique provides a simple proof of the existence results.
Mixing across a density interface produced by grid turbulence

The mixing produced by dropping a horizontal grid through a sharp density interface is examined experimentally. The fraction of the available kinetic energy used to mix the fluid, the flux Richardson number Rf, is measured as a function of the overall Richardson number Ri0. It is found that Rf increases from zero as Ri0 does, reaches a maximum, and then decreases with further increase in Ri0. The final interface thickness is found to be a decreasing function of Ri0, and the equivalent vertical diffusion coefficient is calculated. Qualitative observations of the flow show that the final stages of the decay of motion in the interface are characterized by pancake-shaped modes with large horizontal and small vertical scales.
AC loss measurement of HTS coils with ferromagnetic disks

Manufacturing techniques for low AC loss high-T/sub c/ superconducting coils are necessary to realize high efficiency superconducting power equipments. High-T/sub c/ superconducting tape conductors have anisotropic magnetic field dependence on critical current and AC magnetization loss. A magnetic field component perpendicular to the tape surface degrades HTS coil performance. We numerically investigated a magnetic field adjusting method and AC loss reduction effects by attaching ferromagnetic materials to both ends of HTS coils. We also measured total AC loss of an HTS coil comprising 10 HTS double pancake coils by the boil-off method. Total AC loss of the coil was dominated by mechanical loss due to vibration and movement of conductors and pancake coils. In this paper, methods to reduce total AC loss of HTS coils are discussed.
Secure Transmission Design for Aerial IRS Assisted Wireless Networks

Combining intelligent reflecting surface (IRS) and unmanned aerial vehicle (UAV) offers a new degree of freedom to improve the coverage performance. However, it is more challenging to secure the air-ground transmission, due to the line-of-sight (LoS) links established by UAV. Since IRS is a promising solution for wireless environment reconfiguration, in this paper, we propose an aerial IRS-assisted secure transmission design in wireless networks. In particular, an access point (AP) equipped with a uniform planar array serves several single-antenna legitimate users in the presence of multiple single-antenna eavesdroppers, whose precise positions are unknown. An IRS is mounted on the UAV to help establish desired virtual LoS links between the AP and legitimate users, while ensuring their security. We aim to maximize the worst-case sum secrecy rate by jointly optimizing the hovering position of UAV, the transmit beamforming of AP and the phase shifts of IRS, subject to the requirement of minimum rate for legitimate users. To tackle this non-convex problem, we first decompose it into three subproblems, which are transformed into convex ones via successive convex approximation. An alternating algorithm is then proposed to solve them iteratively. Simulation results show the effectiveness of the proposed scheme and the security improvement by the joint optimization.
A Quantitative Exploration of School Counselors’ Evidence-Based Classroom Management Implementation: Investigating Culturally Sustaining Practices and Multicultural Competence

Considering professional calls for culturally sustaining, comprehensive school counseling practices, this study examined school counselor factors (e.g., age and years of experience) and school factors (e.g., school size and percentage of students of color enrolled) that predicted school counselors’ implementation of evidence-based, culturally sustaining classroom management. We also examined correlations between school counselors’ classroom management and their multicultural practices. The results indicated (a) that age, previous teaching experience, years of school counseling experience, caseload, and percentage of students of color enrolled at school were the strongest predictors of school counselors’ culturally sustaining classroom management implementation and (b) that evidence-based, culturally sustaining classroom instruction is moderately correlated with school counselors’ multicultural behaviors. We offer implications for school counselor practice and preparation, and discuss limitations and future directions.
Comparison of Two Markov Models for a 30-Year Simulation of the Natural History of Intracranial Aneurysms

Objective: There are several Markov models which simulate long-term aneurysm growth and rupture. By comparing multiple models, we cannot only find a way to accurately simulate the growth and rupture behavior of untreated aneurysms in our database, but also find he best model to simulate aneurysm behavior for other studies. This will let us identify which aneurysms require invasive treatment. Methods: We analyzed 290 aneurysms in 29 males and 177 females. The mean diameter was 4.5 ± 3.45 mm, and the mean age was 61 ± 13.22 years. We tested Markov Model I and Markov Model II to simulate growth and rupture over 30 years, and growth and rupture were functions of aneurysm volume. At five-year intervals, we calculated the odds ratio and used the One-Way ANOVA and Independent T-Test to test the effects of aneurysm diameter and growth on the rupture rate. Results: After 30 years, the mean aneurysm sizes were 9.18 ± 2.37 mm and 7.80 ± 6.44 mm for Markov Models I and II, respectively. The mean rupture rate was 13.93% ± 12.89% for Markov Model I and 14.15% ± 21.96% for Markov Model II. There was a significantly higher rupture rate and significant odds ratio for larger aneurysms and “Significant Growth” aneurysms at most five-year intervals. Conclusion: Aneurysms larger than 9.5 mm need immediate surgical treatment. For aneurysms between 3.5 - 9.5 mm, early intervention is recommended if the growth rate exceeds 0.36 mm/year. Markov Model I is the optimal model for our database due to the unrealistically large aneurysms produced by Markov Model II.
Experiences of obstetric nurses and midwives receiving a perinatal bereavement care training programme: A qualitative study

Aim To explore obstetric nurses and midwifery professionals’ experiences with the Perinatal Bereavement Care Training Programme (PBCTP) after implementation. Design A qualitative descriptive design was used. Method This qualitative study was conducted at a tertiary level maternity hospital in China. The PBCTP was implemented at Women’s Hospital School of Medicine, Zhejiang University from March to May 2022. A total of 127 nurses and 44 midwives were invited to participate in the training. Obstetric nurses and midwives studied a 5-module training programme comprised of eight online theoretical courses and submitted a reflective journal after each session. Semi-structured interviews were conducted with 12 obstetric nurses and four midwives from May to July 2022 as a post-intervention evaluation. Thematic analysis was used in data analysis. Findings A total of 16 participants in this study ranged in age from 23 to 40 years [mean age (SD), 30 (4) years]. Six main themes within participants’ experiences of PBCTP intervention were identified: participants’ aims of undertaking the training; personal growth and practice changes after training; the most valuable training content; suggestions for training improvement; directions for practice improvement; influencing factors of practice optimization. Conclusion Nursing and midwifery professionals described the PBCTP as satisfying their learning and skills enhancement needs and supporting positive changes in their care providing for bereaved families. The optimized training programme should be widely applied in the future. More efforts from the hospitals, managers, obstetric nurses, and midwives are needed to jointly contribute to forming a uniform care pathway and promoting a supportive perinatal bereavement care practice.
Static Positioning under Tree Canopy Using Low-Cost GNSS Receivers and Adapted RTKLIB Software

The decrease in costs and dimensions of GNSS receivers has enabled their adoption for a very wide range of users. Formerly mediocre positioning performance is benefiting from recent technology advances, namely the adoption of multi-constellation, multi-frequency receivers. In our study, we evaluate signal characteristics and horizontal accuracies achievable with two low-cost receivers—a Google Pixel 5 smartphone and a u-Blox ZED F9P standalone receiver. The considered conditions include open area with nearly optimal signal reception, but also locations with differing amounts of tree canopy. GNSS data were acquired using ten 20 min observations under leaf-on and leaf-off conditions. Post-processing in static mode was conducted using the Demo5 fork of the RTKLIB open source software, which is adapted for usage with lower quality measurement data. The F9P receiver provided consistent results with sub-decimeter median horizontal errors even under tree canopy. The errors for the Pixel 5 smartphone were under 0.5 m under open-sky conditions and around 1.5 m under vegetation canopy. The adaptation of the post-processing software to lower quality data was proven crucial, especially for the smartphone. In terms of signal quality (carrier-to-noise density, multipath), the standalone receiver provided significantly better data than the smartphone.
Non-linear dispersive waves

A general theory is developed for studying changes of a wave train governed by non-linear partial differential equations. The technique is to average over the local oscillations in the medium and so obtain differential equations for the variations in amplitude, wave number, etc. It corresponds to the Krylov-Bogoliubov averaging technique for the ordinary differential equations of non-linear vibrations. The equations obtained in this way are hyperbolic and can be handled by the usual theory of quasi-linear hyperbolic systems, involving the theory of characteristics and shock waves. In this case the ‘shocks’ are abrupt changes in the amplitude, wave number, etc. They do not involve dissipation, but it turns out that frequency plays the role corresponding to entropy in ordinary gas dynamic shocks. It is not clear whether these shocks will really occur in practice. However, they have a number of interesting properties and seem to be relevant to the discussion of so-called collisionless shocks in plasma dynamics. The main applications envisaged are to water waves and plasma dynamics, and the theory is developed using typical equations from these areas. If the original equations are linear, this theory predicts the usual description of dispersive waves in terms of group velocity, so it may be considered as an extension of the group velocity concept to non-linear problems. Mathematically, the theory may be considered as an extension of some of the methods and ideas for the non-linear ordinary differential equations of vibration theory to partial differential equations.
Dominant tree selection for height estimation and its impact on site classification for African mahogany stands

African mahogany plantations are increasing in Brazil, especially those planted with the species Khaya grandifoliola C. DC. Despite the interest in establishing plantations, there is a lack of studies in management practices for the genus. This makes it difficult to improve methodologies that optimise forest inventory activities, which are essential to support forest management decisions. Therefore, this study aimed to evaluate the effect of the number of trees selected to determine the mean dominant height, and to verify its impact on site classification of African mahogany stands. This will then optimise height sampling and ensure correct site index estimation. To determine the dominant height, 11 treatments were tested, with the selection of 1st to 11th thickest trees per plot, representing between 9 and 102 dominant trees per hectare. The effect of the treatments was evaluated using the values of the mean dominant height and metrics regarding site index classification (stability, stratification capacity and relationship with stand growth). Treatments with inclusion of more dominant trees resulted in a more stable site classification at the expense of a lower correlation with stand growth. Treatments using fewer dominant trees resulted in a greater allocation of plots in the upper site classes, showing that the number of trees used to calculate the dominant height influences the distribution of plots in different site classes. We concluded that Treatments 3 (27 trees ha−1) to 6 (55 trees ha−1) had the best performance, guaranteeing adequate site index estimation. The selection of at least 27 and a maximum of 55 dominant trees per hectare is recommended for African mahogany plantations with low planting densities.
Drug Resistance Genes and Molecular Epidemiological Characteristics of Carbapenem-Resistant Klebsiella pneumonia

Background The global prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) has become a serious challenge for nosocomial infection and attracted worldwide attention. This study explored the drug resistance genes and molecular characteristics for CRKP, providing a reference for nosocomial prevention and control. Methods A total of 42 CRKP isolates were collected from the First Affiliated Hospital of Gannan Medical University (Ganzhou, China) from January 2018 to February 2021. The drug resistance of CRKP was tested by the VitekII Compact system. Drug resistance gene expression was detected by poly-merase chain reaction (PCR), and molecular typing was performed by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Results All the 42 CRKP isolates were multi-drug resistant. Among them, 35 isolates (83.3%) produced blaKPC-2 and 12 isolates (28.6%) produced blaNDM-1. The detection rate of blaIMP-4 and blaOXA-48 was 2.4% (1/42), respectively. Twelve isolates (28.6%) carried both blaKPC-2 and blaNDM-1, one isolate (2.4%) carried both blaKPC-2 and blaIMP-4, and one isolate (2.4%) carried blaKPC-2, blaNDM-1 and blaOXA-48. A variety of other extended-spectrum beta-lactamases (ESBLs) were also detected. All 42 isolates carried blaSHV and blaCTX-M-1, 27 isolates (64.3%) carried blaTEM and 12 isolates (28.6%) carried blaCTX-M-9. The MLST data classified the 42 CRKP isolates into 11 sequence types, mainly ST11, accounting for 61.9% (26/42), of which 92.3% of isolates (24/26) carrying blaKPC-2. The PFGE results demonstrated that the 42 CRKP isolates could be divided into 20 clusters A-T, with cluster A (26.2%, 11/42) and cluster H (21.4%, 9/42) dominating, which were all ST11. Conclusion The CRKP isolates were severely multi-drug resistant, and the main resistant gene was blaKPC-2 production, carrying multiple ESBLs genes simultaneously. The MLST and PFGE revealed that the ST11-blaKPC-2 Klebsiella pneumoniae was the main clonotype. Our findings may offer help to antibiotics selection and nosocomial infection prevention and control.
Topologically unrealizable automorphisms of free groups

Let 0: F-4 F be an automorphism of a finitely generated free group. It has been conjectured (I heard it from Peter Scott) that the fixed subgroup of 4) is always finitely generated. This is known to be so if p has finite order [1], or if + is realiable by a homeomorphism of a compact 2-manifold with boundary [2]. Here we give examples of automorphisms +, no power of which is topologically realizable on any 2-manifold; perhaps the simplest is the automorphism of the free group of rank 3, given by +(x) = y, +(y) = z, +(z) = xy. 1. PV-matrices and automorphisms. By a PV-matrix is meant an n X n integer matrix of determinant + 1, having one eigenvalue, A,, of absolute value greater than 1, and n 1 eigenvalues of absolute value less than 1. The terminology "PV" is used because A, is a Pisot-Vijayaraghavan number [3]. A PV-automorphism of a free abelian group of rank n is an automorphism whose matrix is a PV-matrix, (PV-ness is independent of the basis). A PV-automorphism of a free (nonabelian) group, is an automorphism whose abelianization is PV. 1.1. If M is an n X n PV-matrix and n > 3, then, since 1XI12 . An = 1, no eigenvalue A, is the inverse of any /X. 1.2. If M is a PV-matrix, then every positive integral power Mk is a PV-matrix, since the eigenvalues of Mk are the kth powers of those of M. A simple 3 x 3 example of a PV-matrix is 'O 1 0' E 0 1 i1 1 0 with eigenvalues approximately Al = 1.3247, X2, X3 = -0.6624 + 0.5623\f. Correspondingly, +(x) = y, +(y) = z, ? (z) = xy describes a PV-automorphism of the free group with basis {x,y, z}. 2. Eigenvalues of automorphisms of a 2-manifold. 2.1. Let h: T -> T be an orientation-preserving homeomorphism of a closed, orientable 2-manifold onto itself. Then the eigenvalues of the homology map h*: H l(T) H 1l(T) occur in inverse pairs; that is, they can be listed Al, 2 . , g,I 1 1,2. g-1 Received by the editors September 29, 1980. 1980 Mathematics Subject Classification. Primary 20E05. ' Partly supported by NSF grant MCS 77-04242. O 1982 American Mathematical Society 0002-9939/82/0000-0005/$02.00
Light polarization control in strain-engineered GaAsN/GaAsN:H heterostructures

The expansion of the GaAsN lattice following hydrogen incorporation is spatially patterned so as to generate an anisotropic stress in the sample growth plane. The resulting in-plane symmetry breaking determines an in-plane polarization dependence of the light emitted along the crystal growth direction in agreement with optical selection rules and strain field calculations.