Miracle-dz/UniFAR-FTUs huggingface dataset:
Direct numerical simulation of the turbulent kinetic energy and energy dissipation rate in a cylinder wake

Abstract Abstract The turbulent kinetic energy and energy dissipation rate in the wake of a circular cylinder are examined at a Reynolds number of 1000. The turbulence characteristics are quantified using direct numerical simulation, which provides a comprehensive dataset that is almost impossible to acquire from physical experiments. The energy dissipation rate is decomposed into the components due to the mean flow, the coherent primary vortices and the remainder. It is found that the remainder component, which develops only in a three-dimensional turbulent wake and resides mainly in the regions of vortices, accounts for 95 % and 97 % of the total dissipation rate for 10 and 20 cylinder diameters downstream of the cylinder, respectively (while the remainder accounts for 62 % and 83 % of the total turbulent kinetic energy). Based on the remainder component, the validity of local isotropy, local axisymmetry, local homogeneity and homogeneity in the y–z plane for the turbulent dissipation in the wake is examined. The analysis reveals that the turbulent dissipation is largely locally homogeneous, but not locally isotropic or axisymmetric, even after the annihilation of the primary vortex street. In addition, the performances of the four corresponding surrogates to the true dissipation rate are evaluated. Owing to the general validity of local homogeneity, the surrogates of local homogeneity and homogeneity in the y–z plane perform well. Although local axisymmetry does not hold, the corresponding surrogate performs well, because errors from different terms largely cancel out. However, the surrogate of local isotropy generally underestimates the true dissipation rate.
On the dual reciprocity boundary element method

The Dual Reciprocity Boundary Element Method (DRBEM) is thus far the most powerful numerical technique to tackle elliptic, parabolic, or hyperbolic type differential equations, while maintaining the elegance of the Boundary Element Method. In this thesis, the details of DRBEM are examined and discussed, with respect to the two-dimensional versions of partial differential equations of type V̂ w = b(X, y, u, u^, Uy, uj, posed in a bounded (interior) or unbounded (exterior) region. For interior problems, the problem associated with the traditional DRBEM, i.e., the singularities created by differentiating the interpolation functions sometimes leading to large numerical errors, is first pointed out. Then two remedies for this problem are given, supported by a number of numerical experiments. As to exterior problems, heretofore little effort has been made and the only approach available by now is far from completeness and satisfaction. Therefore an endeavour is made to extend DRBEM from interior problems to exterior problems. The robustness and reliability of the newly proposed approach are supported by the numerical tests so far completed.
Isoperimetric and Analytic Inequalities for Log-Concave Probability Measures

We discuss an approach, based on the Brunn–Minkowski inequality, to isoperimetric and analytic inequalities for probability measures on Euclidean space with logarithmically concave densities. In particular, we show that such measures have positive isoperimetric constants in the sense of Cheeger and thus always share Poincare-type inequalities. We then describe those log-concave measures which satisfy isoperimetric inequalities of Gaussian type. The results are precised in dimension 1.
RMHP_A_304040 1999..2010

1Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, 110004, People’s Republic of China; 2Department of Endocrinology, Shengjing Hospital of China Medical University, Shenyang, 110004, People’s Republic of China; 3Department of Emergency Medicine, Shengjing Hospital of China Medical University, Shenyang, 110004, People’s Republic of China Abstract: Preeclampsia has a significant long-term effect on the health of both mothers and babies. Preeclampsia-related pregnancy complications increase the morbidity and mortality of pregnant women and their fetuses by 5–8%. The recent advancement of assisted reproductive technology, combined with a rise in the number of elderly pregnant women, has resulted in pregnancy incidence with twins. Twins pregnant women have a 2–3 times greater risk of developing preeclampsia than singleton pregnant women, and it happens sooner and progresses faster. It is more severe and may appear in an atypical way. End-organ damage, such as renal failure, stroke, cardiac arrest, pulmonary edema, placental abruption, and cesarean section, are related maternal complications. Fetal growth retardation, stillbirth, and premature delivery with obstetric signs are all fetal complications. According to studies, all multiple pregnancies can take low-dose aspirin (60–150 mg) to minimize the risk of preeclampsia. To improve pregnancy outcomes and reduce the inherent risk of pregnancy with twins, twins should be handled as a high-risk pregnancy and treated differently than singletons. The literature on twin pregnancy with preeclampsia is the subject of this review. It will examine the current state of research on preeclampsia in pregnancy with twins, including the occurrence, diagnosis, and pathophysiological process. Moreover, the effect of pregnancy with twins on the perinatal outcome and pregnancy management of pregnancy with twins, including blood pressure management and preeclampsia prevention and treatment, is examined in this literature review. The goal is to figure out what kind of diagnosis and care you may need.
Estimation of the radial variation of seismic velocities and density in the earth

An inversion procedure is developed to estimate the radial variations of compressional velocity, shear velocity, and density in the Earth. The radial distributions are defined as spherically symmetric averages of the actual distributions in the laterally heterogeneous Earth, and the nature of the averaging implied by averaging certain sets of eigenperiod and travel-time data is examined. For travel-time data, the spherical averaging yields the Terrestrial Monopole if the data sample a distribution derived from a uniform distribution of sources and receivers. Since this is difficult to obtain for absolute times, differential travel times are used to constrain the velocities. It is shown that the bias inherent in available sets of differential travel-time data is considerably less than that in equivalent sets of absolute travel-time data, if the phase combination is suitably chosen. Observations are presented for the phase combinations PcP-P, ScS-S, P'(AB)-P'(DF), and P'(BC)-P'(DF). The inversion algorithm developed is based on a linear approximation to the perturbation equations and is shown to provide a stable method for estimating the radial distributions of velocities and density from a finite number of inaccurate data. The linear inversion theory presented is complete; it allows one to estimate the resolving power of the data and the resolvability of specified features in the model. Three estimates of the radial distributions are derived using an extensive set of eigenperiod and travel-time data. One model, designated model B1, fits 127 of the 177 eigenperiods of the Dziewonski-Gilbert set within their formal 95% confidence intervals. This model satisfies extensive sets of auxillary data as well. It is shown from resolving power calculations that little information is lost by using differential travel times in lieu of absolute times. It is demonstrated that the nature of the averaging in the estimation procedure for given sets of gross Earth data can be improved by judicious specification of the norm on the space of models.
The Gravitational Mass at the Superconducting State

It will be shown that the gravitational masses of the electrons of a superconducting material are strongly negative. Particularly, for an amount of mercury (Hg) at the transition temperature, Tc = 4.15 K, the negative gravitational masses of the electrons decrease the total gravitational mass of the Hg of approximately 0.1 percent. The weight reduction increase when the Hg is spinning inside a magnetic field or when it is placed into a strong oscillating EM field.
Two types of shock in the hotspot of the giant quasar 4C74.26: a high-resolution comparison from Chandra, Gemini and MERLIN

NewChandra observations have resolved the structure of the X-ray luminous southern hotspot in the giant radio quasar 4C74.26 into two distinct features. The nearer one to the nucleus is an extremely luminous peak, extended some 5 kpc perpendicular to the orientation of the jet; 19 kpc projected further away from the central nucleus than this is an arc having similar symmetry. This X-ray arc is cospatial with near-infrared (near-IR) and optical emission imaged with Gemini and radio emission imaged with Multi-Element Radio-Linked Interferometer Network (MERLIN). We explore how this double feature corresponds to two shocks having very different characteristics in spectral energy distribution. We present the case that these observations are explained by the luminous X-ray peak being synchrotron emission with a flux density of ∼7 nanoJy. There is no steep spectrum radio, optical or near-IR emission directly associated with this shock. Beyond this point in the jet’s flow, and following adiabatic losses, at least 19 kpc further downstream where the flow impinges on the intergalactic medium, the arc structure seen in sharp focus at radio wavelengths appears to be approximately mimicked at near-IR, optical and X-ray wavelengths. The radio emission is most naturally explained as synchrotron emission, but it would be unnatural to explain the X-rays as arising from the same emission mechanism since they show a non-monotonic spectrum. They are, however, explicable as inverse Compton scattering of photons in the cosmic microwave background, though this requires that the magnetic field strength in this slender arc/shock region responsible for the associated synchrotron radio emission is just a few per cent of the minimum energy value. The angular separation of the double shock structure (itself 19 kpc or 10 arcsec in size) from the active nucleus which fuels them of ∼550 kpc could present a challenge for connecting ‘unidentified’ hard X-ray or Fermi sources with their origins.
Inequality measurement and the leaky-bucket paradox

The transfer principle requires inequality measures to decrease for mean preserving contractions. How much leakage of transfers can preserve inequality? Conditions are shown for leaky transfers to preserve inequality. We find that positive remainders with positive or negative leakage as well as negative remainders with positive leakage may occur. This constitutes the leaky-bucket paradox.
Radial variation of the interplanetary magnetic field between 0.3 AU and 1.0 AU - observations by the Helios-1 spacecraft

We have investigated the radial dependence of the radial and azimuthal components and the magnitude of the interplanetary magnetic field obtained by the Technical University of Braunschweig magnetometer experiment on-board of Helios-1 from December 10, 1974 to first perihelion on March 15, 1975. Absolute values of daily averages of each quantity have been employed. The regression analysis based on power laws leads to 2.55 y x r- 2·0, 2.26 y x r- i.o and F = 5.53 y x r- i. 6 with standard deviations of 2.5 y, 2.0 y and 3.2 y for the radial and azimuthal components and magnitude, respectively. Here r is the radial distance from the sun in astronomical units. The results are compared with results obtained for Mariners 4, 5 and 10 and Pioneers 6 and 10. The differences are probably due to different epochs in the solar cycle and the different statistical techniques used.
Quality spatial variability of arabica coffee and its relationship with Brix degree and fruit reflectance.

The coffee quality is mainly defined by the fruit ripeness stage. The maximum quality is achieved when the fruits meet an appropriate chemical composition. The objective of this study was to analyse the quality spatial variability of arabica coffee and its relationship with fruit ripeness, characterized by the concentration of total sugars, measured by the brix degree, and by the reflectance of cherry fruit. The study was performed in the 2011 harvest season in Araponga, Minas Gerais, Brazil. We sampled about 30 plants per hectare, randomly chosen, of which the cherry fruits were harvested by hand. From each sample, twenty fruits were randomly taken, of which the reflectance was measured using a spectroradiometer FieldSpec Pro. Using the same fruits, the brix degree of the fruit juice was measured using a portable refratrometer. After this analysis, the fruits were depulped and then dried artificially to 11% wet base moisture content. The coffee cup quality analysis was performed in accordance with the standards presented by the Brazilian Specialty Coffee Association (BSCA). We generated maps of coffee cup quality, brix degree and fruit red band reflectance. From the maps, there were individual analysis of spatial autocorrelation using Moran\'s Index and also the analysis of spatial correlation between the variables involved in the study. Only the values of ° Brix showed spatial variability. The reflectance in the red band showed high correlation with the quality of the coffee cherry, while the degree brix was not able to detect the same variation, with no significant correlation between them.
OPERATOR MULTIPLIERS

We introduce a noncommutative version of Schur multipliers relative to an operator ideal. In this setting the functions of two variables are replaced by elements from a tensor product of C*-algebras, and the measures (or spectral measures) by representations. For commutative C*-algebras this approach agrees with Birman and Solomyak’s theory of double operator integrals. We study the dependence of the spaces of multipliers on the choice of representations and ﬁnd that the question is closely related to Voiculescu and Arveson’s theory of approximately equivalent representations. The space of multipliers universal with respect to the chosen measures is related to the Haagerup tensor product of the algebras.
A classification of 2-dim Lattice Theory

A unified classification and analysis is presented of two dimensional Dirac operators of QCD-like theories in the continuum as well as in a naive lattice discretization. Thereby we consider the quenched theory in the strong coupling limit. We do not only consider the case of a lattice which has an even number of lattice sites in both directions and is thus equivalent to the case of staggered fermions. We also study lattices with one or both directions with an odd parity to understand the general mechanism of changing the universality class via a discretization. Furthermore we identify the corresponding random matrix ensembles sharing the global symmetries of these QCD-like theories. Despite the Mermin-Wagner-Coleman theorem we find good agreement of lattice data with our random matrix predictions.
Collisions between the nucleus of comet Halley and dust from its own meteoroid stream

As Comet Halley orbits the Sun it continuously ploughs through its own meteoroid stream. We show that the collision velocity between the stream meteoroids and the surface of the cometary nucleus is far from negligible, the mean value being about 4.0 km s −1 . Half of the collisions occur when the comet is close to perihelion. The total amount of its own dust hit by Comet Halley per orbit is around 17 g, and this damages a mere 8×10 −8 per cent of the surface of the nucleus
Urban air temperature anomalies and their relation to soil moisture observed in the city of Hamburg

The spatial variability of the urban air temperature for the city of Hamburg is analyzed based upon a one-year dataset of meteorological and pedological measurements. As local air temperature anomalies are subject to land-use and surface cover, they are monitored by a network of measurement stations within three different urban structures. Mean annual temperature deviations are found to be +1.0 K for inner city sites and +0.25 K to −0.2 K for suburban sites compared to a rural reference. The nocturnal urban heat island (UHI) is identified and averages +1.7 K at the inner city stations, +0.7 K at a suburban district housing area and +0. 3K at a nearby green space. The observed UHI effect is most prominent when the wind speed is low (≤ 2m s −1 )a nd the sky is only partly cloudy (≤ 6/8 th ). In spring 2011 an average inner city UHI of up to +5.2 K is observed during situations matching these conditions, while the extraordinary dry fall of 2011 lead to remarkably high air temperature differences at all observed stations. As expected, no evidence for a significant impact of topsoil moisture on nighttime UHI effect is found. The analysis of air temperature anomalies during daytime results in an annual mean deviation of −0.5 K above unsealed, vegetated surfaces from a sealed site during days with a turbulent mixing induced by wind speed > 2m s −1 . Here, there is an indication for a relation between the water content of upper soil layers and the warming of air: 11 to 17 % of the variance of the diurnal air temperature span is found to be explained by the soil water content for selected relevant days.
Competence and governance in strategic collaboration: The differential effect of network structure on the creation of core and non-core technology

Whereas most of the literature on the benefits of alliances for learning and innovation has taken on a competence perspective, this paper provides an alternative integrated framework based on both a competence and governance point of view. The former focuses on the role of knowledge flows as means to access new knowledge, whereas the latter is centered around the core concepts of opportunism and freeridership in knowledge exchange situations. Although it has generally been acknowledged that competence-based benefits of collaboration may come at a price of elevated risks due to knowledge spillovers and freeridership, such a governance view remains understudied. This paper explains how a firm’s alliance network structure affects benefits as well as risks of collaboration in the context of the creation of core and noncore technology. In the case of core technology, firms attach more value to reducing governance-based risks relative to obtaining competence-based benefits. The opposite is found when firms develop noncore technology. This paper contributes to the existing literature by going beyond the common idea that competence and governance perspectives are either complementary or competing. Instead, this study shows that for technology-based collaboration, they can both apply at the same time, implying a trade-off in some cases and offering synergy in other cases. Basedonanempiricaltestinthreedifferentindustries(pharmaceuticals,chemicals,andautomotive),thereissupport for most of our hypotheses. Direct ties have an inverted U-shaped effect on both core and noncore technology, and the effect is relatively stronger for the former. The results furthermore show that indirect ties play a positive role in noncore technology development and that this effect is not hampered by the number of direct ties a firm has. In contrast, indirect ties seem to hamper core competence development when companies have a lot of direct ties. Finally, firms are found to benefit from nonredundancy in their alliance network in their efforts to strengthen their core technology. The joint effect of these three network characteristics leads to optimal results for core and noncore technologies under quite different alliance network structures. This poses a problem for the ambidexterity of companies, when they simultaneously try to strengthen core and noncore technologies.
Optimal plot size in buckwheat Tamanho ótimo de parcela em trigo mourisco

Highlights The three methods for determining the optimal plot size generate different results. A plot size of 7.60 m 2 is the reference for experiments with buckwheat. Information is provided for improving experimental precision in buckwheat. Abstract The aim of this work was to compare three methods of estimating the optimal plot size for evaluating fresh matter in the IPR91-Baili and IPR92-Altar cultivars of buckwheat ( Fagopyrum esculentum Moench). Sixteen uniformity trials (blank experiments) were conducted, eight with the IPR91-Baili cultivar and eight with the IPR92-Altar cultivar. The trials were carried out at eight different sowing times. The fresh matter was evaluated in 576 basic experimental units (BEU), each 1 m × 1 m in size (36 BEU per trial). The optimal plot size was determined using the method of modified maximum curvature, the linear response plateau model and the quadratic response plateau model. The optimal plot size differs between methods, and decreases in the following order: quadratic response plateau model, linear response plateau model and modified maximum curvature. The optimal plot size for evaluating fresh matter in the IPR91-Baili and IPR92-Altar cultivars of buckwheat is 7.60 m 2 . This size can be used as a reference for future experiments with buckwheat.
Study of micron-thick MgB2 films on niobium substrates

1 µm thick polycrystalline MgB2 films have been grown on commercial niobium sheets using the hybrid physical–chemical vapour deposition technique (HPCVD). Their zero-resistance transition temperature Tc0 ranges from 38 to 39 K and the transition temperature width ΔTc is about 0.1–0.2 K. The films are composed of regular plate-shaped MgB2 crystallites and have lattice constants about the bulk values. Some diffusion regions were observed at the interface between the film and the substrate by a line scanning spectra of energy-dispersive x-ray spectroscopy (EDX) on the cross section, which might enhance the adhesion of the coated layer to the substrate. The critical current densities, Jc, of these films, calculated by the Bean model, are greater than 5 × 106 A cm−2 at 10 K in zero field. Although tiny cracks in the film were created by bending the sample on a curved surface with a radius of 1.4 mm, however, Tc0 of the bent film was not affected and remained about 39 K, which indicates that the sample has a certain ductibility.
Scattering solutions and Born approximation for the magnetic Schr\"odinger operator

We prove the existence of scattering solutions for multidimensional magnetic Schr\"odinger equation which belong to the weighted Sobolev space H^1_s (R^n)(n=2,3) with some s < -1/2. As a consequence of this we formulate the direct Born approximation for the magnetic Schr\"odinger operator. Possible connections with inverse problems (inverse scattering Born approximation) are discussed.