Miracle-dz/UniFAR-FTUs huggingface dataset:
Active optics performance study of the primary mirror of the Gemini Telescopes Project

A study on the evaluations of the active optics system performance for the primary mirror of the Gemini telescopes project was conducted. Finite element analysis was employed to analyze the optical surface figures of the primary mirror. Four distinct influence matrices (generic 3-point kinematic system, combined unit case, 3-zonal multiple constraint system, and high frequency localized force set) were established based on the unit load cases at each of 120 active support locations and the restraint boundary conditions in the mirror model. A least square algorithm was developed. This scheme is able to accommodate the design constraints in the active optics systems. The active optics performances were evaluated by analyzing their capabilities in compensating the optical surface figures. For each active system, the level of the calculated active forces and the surface residual errors were examined. The results indicated that their performances are excellent and are in good agreement for most sampling surface figures. The results from the active optics performances based on the generic, the combined, and the 3- zone cases were practically identical for all the object surfaces. The active optics system based on the high frequency localized force set tends to predict a higher surface RMS error and requires a bigger force set. This effect became apparent when this system was applied to correct the surfaces from the natural mode analyses.
Eigensensitivity analysis for differential-algebraic power system models

The authors present a method for the determination of the sensitivity of the dominant critical mode of a system to changes in system control parameters. The method is used to determine optimal locations for the siting of static VAR compensator devices to improve the system dynamic limit. The method is based on an augmented formulation which includes both differential and algebraic models explicitly. The sparsity of power system models is retained by the use of the augmented formulation. The proposed method is computationally efficient and complements other design methods such as participation factors and transfer function residue methods. <<ETX>>
Visualization and Measurement of Flow over a Cylindrical Surface with a Bump

The complex flowfield around a cylindrical bump with a hemispherical free end mounted on a cylindrical surface has been studied by means of liquid-crystal flow visualization, surface-pressure measurements, and cross-hot-wire anemometry. This setup constitutes a prototype of a typical wall-mounted sensor on an aircraft. The slenderness parameter of the bump is one and the curvature of the hemispherical ending starts at the half-height of the bump. The radii of both the cylindrical and hemispherical parts of the bump are equal. The thickness of the turbulent boundary layer over the cylindrical surface, which controls the location of the separation over the bump's surface, is smaller than the bump height at the position at which the bump is located. The flow over the hemispherical free end separates further downstream than does the flow over the cylindrical part of the bump. The size of the recirculation region downstream of the bump is larger than the recirculating region of a finite cylinder with a flat end. A Reynolds number dependence of the reattachment point behind the bump is observed. Large turbulence fluctuations exist because of the interaction between the downwash and the turbulent boundary layer developing over the ground surface. The upstream disturbance of the bump, retardation due to an adverse pressure gradient, and push up of the flow due to the finite length of the bump are also captured by the velocity measurements. Effects due to the curvature of the surface plane are not detectable far downstream of the bump.
Occurrence and identification of Penicillium and Talaromyces species from beach sand

Aims: Penicillium and Talaromyces were among the species of microfungi that inhabit beach sand in Batu Ferringhi Beach, Penang Island, Malaysia. Previously, Talaromyces was described as the sexual stage of Penicillium , but both are now accepted as separate genera based on molecular phylogeny. The aim of the present study was to identify species of Penicillium and Talaromyces that are present in beach sand in Malaysia. Methodology and results: Species identities were confirmed according to similarities of the internal transcribed spacer regions and β-tubulin gene sequences and a phylogenetic analysis based on both regions/gene. Nine Penicillium spp. were identified as P. georgiense , P. chermesinum , P. pimiteouiense , P. citrinum , P. oxalicum , P. daleae , P. rolfsii and Penicillium sp. and the four Talaromyces spp. were T. siamense , T. atroroseus , T. minioluteus and T. fusiformis . Conclusion, significance and impact of study: These findings showed that beach sand harboured a variety of Penicillium and Talaromyces species. The occurrence of Penicillium and Talaromyces in beach sands is associated with the organic matter in the sand, which provides suitable substrates and nutrient sources. Due to this, beach sand might harbour many potentially pathogenic or opportunistic species that may pose a health concern to immunocompromised individuals.
Stability radii for some propagation models

The simple idea of Hinrichsen & Pritchard (1986a,b), who defined the structured stability radius, has proved to be unexpectedly fruitful, generating a large amount of work and making interesting connections (Hinrichsen & Pritchard 1988, 1989; Hinrichsen & Motscha 1988; Hinrichsen et al. 1989; Hinrichsen & Son 1991; Pritchard & Townley 1989, 1990; Rasvan 1993). In this paper we shall discuss stability radii for a class of applications concerning systems with propagation. Such systems are described by simple lossless telegraph equations and include the practical cases of physical systems containing lossless steam, gas, or water pipes or electrical circuits containing lossless LC transmission lines. We shall state in a natural way the problem of a structured stability radius for such models. To estimate such radii we shall use a frequency-domain approach of Popov (1973) and Yakubovich (1978), as suggested by the known formulae of Hinrichsen & Pritchard. Our specific models lead to a general differential difference equation coupled with a diference equation.lt could be possible to express such systems as abstract evolution equations (see for instance the paper of Weiss (1994) on regular systems) and then use the general results by Pritchard & Townley (1990). We do not intend here to compete with such approach. Our aim here is to point out some examples of naturally occuring, practical problems where the stability radius has to be considered and then to draw attention to the possibility of approaching the problem with •methods similar to the ones used in absolute stability. It is hoped that existence of several approaches to the problem will stimulate further research concerning comparisons between them, both from the view-point of the tightness of estimates as well as from the view-point of simplicity, directness, and accessibility.
Moderate-aspect-ratio elliptical cylinders in simple shear with inertia

The effects of fluid inertia, geometry and flow confinement upon the dynamics of neutrally buoyant elliptical and non-elliptical cylinders over a wide range of aspect ratios in simple shear are studied experimentally for moderate shear-based Reynolds numbers Re. Unlike circular cylinders, elliptical cylinders of moderate aspect ratio cease to rotate, coming to rest at a nearly horizontal equilibrium orientation above a critical Reynolds number Recr (‘stationary behaviour’). Simple dynamics arguments are proposed to explain the effects of aspect ratio and flow confinement upon critical Reynolds number and particle dynamics. Experiments confirm results from previous numerical simulations that the normalized rotation period for Re < Recr (‘periodic behaviour’) is proportional to (Recr − Re)−0.5 for small Recr − Re. For periodic behaviour, maximum and minimum angular cylinder speeds both decrease, and period increases, as Recr − Re decreases. For stationary behaviour, the cylinder rotates until it achieves a nearly horizontal equilibrium orientation, which increases as the Reynolds number approaches the critical value. The experimental results are in good agreement with previous lattice-Boltzmann simulations for a 0.5 aspect ratio cylinder. Variation in angular speed over a rotation period decreases as aspect ratio increases, while Recr increases as flow confinement and aspect ratio increase. A non-elliptical cylinder of 0.33 aspect ratio also ceases to rotate above a certain Reynolds number. Although Recr is different from the corresponding elliptical case, the scaling of the normalized rotation period for this body as Recr → Re is identical to that for the elliptical cylinder, suggesting that this scaling is independent of particle shape (i.e. ‘universal’, as conjectured in previous numerical studies). The results also demonstrate that a variety of centrosymmetric bodies with aspect ratios below unity transition from periodic to stationary behaviour.
Effects of reduced dimensionality in the relaxation dynamics of ionic conductors

We report on the dispersive ionic conductivity in Li0.5 − xNaxLa0.5TiO3 (0 ≤ x ≤ 0.5), where the number of available positions for the mobile Li ions is reduced by introducing immobile Na ions. At high frequency the conductivity is power law dependent with an exponent which increases as the number of accessible neighboring sites decreases. This result is quantitatively accounted for in terms of a one-parameter statistical microscopic model. We provide experimental and theoretical evidence for the importance of reduced dimensionality resulting from the blocked pathways in slowing down the dynamics of diffusing ions.
Stress field induced by swift heavy ion irradiation in cubic yttria stabilized zirconia

X-ray diffraction (XRD) was used to investigate the damage and the correlated stress induced by the slowing down of swift heavy ions in cubic zirconia polycrystals doped with 10 mol % Y2O3. Samples were irradiated at room temperature with 940 MeV Pb ions at fluences ranging from 5×1011 to 4×1013 cm−2. Changes of XRD profiles were examined at increasing fluences. Residual macroscopic stresses induced by irradiation were determined using XRD by the “sin2 ψ method. ” The state of stress in the irradiated layer was described by a combination of: (i) a hydrostatic stress caused by the formation of damaged tracks leading to swelling and (ii) a biaxial stress imposed by the bulk undamaged material, which controls the lateral expansion of the surface damaged layer. The evolution of the stress as a function of irradiation fluence was also determined: the intensity of the hydrostatic stress increases from 80 to 460 MPa when the fluence is increased from 5×1011 to 4×1013 cm−2 and that of the biaxial stress increases .
A New Generalized “Exposure-Based” Segregation Index

Interest is growing in the neighborhood segregation of Hispanics as well as blacks in U.S urban areas. This article shows how “exposure-based” or p* indexes of segregation may be generalized for analyses of the segregation of three or more groups, and demonstrates the application of the “generalized segregation index” in the Denver and Houston regions. Exposure-based segregation indexes measure the degree to which a group is geographically exposed to (or isolated from) other groups in neighborhoods. Exposure-based indexes are believed by many to be of somewhat greater relevance for fair housing policy than is the index of dissimilarity.
Assessing End of Phase 2 Decision Criteria

The objectives of the Phase 2 stage in a drug development program are often to evaluate the safety and tolerability of different doses, select a promising dose range, and look for early signs of activity (i.e., to establish proof of concept). At the end of Phase 2 (EOP2), a decision to initiate Phase 3 studies is made that involves the commitment of considerable resources. One of the key factors in this decision is the expected efficacy and the associated predicted probability of success (PoS) in Phase 3. Making a decision based upon the PoS requires decision makers to select a benchmark (or PoS criterion) for the PoS, which if achieved would enable a “go-to-Phase 3” decision. However, appropriately choosing the criterion requires knowledge of the operating characteristics associated with the decision criteria. A key operating characteristic that a funder/sponsor requires to make such a choice is to understand the predicted conditional probability of making a go decision and subsequently failing in Phase 3. In this article, we show how such risks can be informed through the use of clinical trial simulation. We also highlight through a worked example in pancreatic cancer how this simulation exercise can help to decide between different development strategies for a specific indication. Supplementary materials for this article are available online.
Excluded-volume potential for rigid molecules endowed with C2v symmetry

The excluded volume of a pair of molecules is proportional to the second virial coefficient in hard-core models that represent, for instance, the reference model in perturbation approaches to statistical theories of fluids [see, e.g. Chap. 5 of Kalikmanov, V. (2001), Statistical Physics of Fluids. Texts and Monograph in Physics, Springer, Berlin]. In three space dimensions, there exist exact results for convex molecules and in fact lack of convexity has been a major obstacle in applying the mathematical techniques employed in the convex case. In this paper, we illustrate how a mixed—analytical and numerical—method can be used to obtain exact expressions of the excluded volume for a pair of non-convex molecules conceived as aggregates of hard spheres; these can model van der Waals regions associated to the atoms forming each molecule. To compute the excluded volume for molecules endowed with C2v symmetry, modelled as chains of tangent hard spheres, we adapt a numerical code available to the scientific community. Because the result is a rather cumbersome expression in term of the relative orientation of the interacting molecules, we expand it over a suitable set of symmetry adapted Wigner functions to build up approximate, but faithful expressions, and we also prove analytical results announced elsewhere [Bisi, F. , Durand, G. , Rosso, R. & Virga, E. (2008), Polar steric interactions for v-shaped molecules. Phys. Rev. E, 78, 011705].
Polarization of radiation scattered in magnetized turbulent envelopes

We consider the single scattering of the non-polarized radiation of a central star on the electrons of a plasma circumstellar envelope. We assume that such an envelope is magnetized and consists of a turbulent plasma. Two types of envelopes are considered: a spherical envelope with the dipole magnetic field and a cone-like jet with the radial magnetic field. It is shown that the existence of turbulent motions in the envelopes drastically changes the polarization degree spectrum $p(\lambda )$ and the positional angle spectrum $\chi(\lambda )$ of scattered radiation compared to the non-turbulent case. The difference in spectra can be used to estimate the ratio for the energy of magnetic fluctuations to the energy of a regular magnetic field.
THE HEARING OF SPEECH IN AUDITORIUMS

A summary is given of the quantitative effects of loudness, reverberation, noise and the shape of an auditorium upon the hearing of speech in auditoriums. The average loudness of speakers is found to be about 50.7 db in small auditoriums (27,200 cu. ft.) and 45.7 db in large auditoriums (240,000 cu. ft.). The loudness of spech in large auditoriums is therefore at a critically low level, so that slight disturbances from reverberation or noise suffice to make hearing conditions unsatisfactory. The percentage articulation in an auditorium is ascertained by means of the formula, Percentage Articulation = 96k1kτknks, where k1, kτ, kn and ks are the reduction factors owing to diminution of loudness, reverberation, noise, and shape of auditorium, respectively. Methods and data are given for determining these reduction factors. A study of the combined effects of loudness and reverberation yields the optimal times of reverberation for the hearing of speech in auditoriums of different sizes. Thus, the optimal time .
A capture± recapture survival analysis model for radio-tagged animals

In recent years, survival analysis of radio-tagged animals has developed using methods based on the Kaplan-Meier method used in medical and engineering applications (Pollock et al. , 1989a,b). An important assumption of this approach is that all tagged animals with a functioning radio can be relocated at each sampling time with probability 1. This assumption may not always be reasonable in practice. In this paper, we show how a general capture-recapture model can be derived which allows for some probability (less than one) for animals to be relocated. This model is not simply a Jolly-Seber model because it is possible to relocate both dead and live animals, unlike when traditional tagging is used. The model can also be viewed as a generalization of the Kaplan-Meier procedure, thus linking the Jolly-Seber and Kaplan-Meier approaches to survival estimation. We present maximum likelihood estimators and discuss testing between submodels. We also discuss model assumptions and their validity in practice. An exa.
Interference Microscope with Total Wavefront Reconstruction

An interference microscope is described, constructed in 1951–56, in which three-dimensional objects can be reconstructed, correctly incorporating amplitudes and phases, from two photographs simultaneously taken on one plate. These photographs are “holograms,” that is to say, records of the interference of the image-carrying wave, split in two, with a coherent background wave, also split in two. A phase difference of a quarter wave is produced, for the two otherwise identical photographs, between the image-carrying waves and their respective coherent backgrounds. The two photographs are in sine–cosine or “quadrature” relation; between them they contain the full optical information. If they are illuminated in such a way that there is a difference of a quarter wave in the phases at two corresponding points, and if the two beams are united, the original image-carrying wave is restored correctly in amplitude and in phase. An essential part of the instrument is a “quadrature prism”; a beam splitter with a three-layer sandwich, which establishes the quadrature relation in the taking of the holograms.The microscope has the advantage that it need not be focused, as it gives a three-dimensional reconstruction. Moreover, photographs can be taken with 1/10 or even 1/100 of the light required for exposure going through the object; the rest of the energy is supplied by the background beam, which is 10–100 times stronger, and which goes around the object.Many details of the instrument are now out of date owing to the invention of the laser. Alternative methods which have now become possible are discussed for realizing the principle of total reconstruction.
The role of mass transfer in describing the dynamics of mesoscale convective systems

When deep convection occurs in a rotating stratified fluid, potential vorticity (PV) anomalies form in response to the change in the mass field. This geostrophic adjustment process, and its importance in shaping the dynamics of long‐lived convective systems, is studied using a high‐resolution numerical model to simulate idealized precipitating and non‐precipitating convection.
FLAVOR LEPTON NUMBER VIOLATION AT LEP2

We show that in some supersymmetric models with explicit flavor number violation due to soft supersymmetry breaking terms there is strong flavor lepton number violation in slepton decays due to slepton mixing. If sleptons are relatively light (msl ≤ MZ) flavor lepton number violation could be discovered at LEP2.
Identification of Long-Range Transported Haze Phenomena and Their Meteorological Features over Northeast Asia

AbstractThis paper presents a technique used to empirically classify operationally defined “haze” days in South Korea from 2000 to 2007 into long-range transported (LRT) and stagnant (STG) haze cases. A total of 547 haze days were classified into these two cases by tracking consecutive 6-day synoptic weather charts and air trajectories. The meteorological features associated with long-range transport of haze were identified by contrasting the values of 35 candidate meteorological parameters corresponding to the two types of haze cases. A suitable subset of synoptic variables was then chosen to diagnose the unique meteorological features of each case. The statistical test showed that geostrophic wind speed, vorticity, vorticity advection at a geopotential height of 850 hPa, and the vertical stability index of the lower atmosphere were indicated as highly effective parameters for distinguishing between the LRT and STG cases. The classification accuracies showed 93.2%, 87.8%, 85.4%, and 84.4% for these four .
Stabilized efficient single-frequency Nd:YAG laser

It is shown how intracavity etalons can be optimally designed for axial mode selection and frequency stabilization of gas and crystal lasers. Relevant laser parameters, required etalon properties, and expected losses are determined. A simple frequency stabilization scheme based on birefringent etalons is described, which does not require laser modulation. Major problems associated with stable single-frequency operation of solid-state lasers are discussed. Using an optimally designed crystal quartz etalon, a Nd:YAG laser could be stabilized to 10-7in frequency and 2 percent in amplitude. The linearly polarized single frequency TEM 00 output was 150 mW, which compares to an unpolarized 12-mode output of 400 mW for the bare laser.
Edge-guided filtering scheme for decomposition-based tone mapping

This paper presents a novel edge-guided filtering scheme for decomposition-based tone mapping, whose superiority is to prevent two major defects in filter-driven multi-scale decomposition: halo artifact and over-smoothing distortion. First, we calculate an edge-preserving smoothing by gradient domain reconstruction with given edges. Then we apply this output in high dynamic range tone mapping to address aforementioned problems. At last, some experimental results are presented to demonstrate the effectiveness of our method in producing high-quality low dynamic range outputs.
Solution of the basic equation of stellar statistics

The basic equation of stellar statistics connects the probability density function of a measurable quantity with the probability density of two variables, which cannot be observed directly, by the Bayes theorem of conditional probabilities. The resulting relation is a Fredholm-type integral equation of the first kind. If the two background variables are statistically independent we recover the convolution equation. The analytical solution based on the Fourier transformation is very sensitive to high-frequency noise. Eddington's solution attempts to find the unknown function in form of a series Sigma gamma jh(i)(z). Malmquist's method computes the conditional probability of the unknown variable assuming that the observed variable is given. The statistical aspect of the problem is expressed if one uses Lucy's algorithm which is a particular form of the more general EM algorithm. Dolan's matrix method solves numerically the matrix equation which approximates the integral equation. Methods are superior which retain the true statistical nature of the problem.
Light extraction: what we can learn from fireflies

Fireflies lighten up our warm summer evenings. There is more physic behind these little animals than anyone of us could imagine. In this paper we analyze from a physical point of view one structure found on the firefly lantern, the one which best improves light extraction. Moreover, simulations will be done to show why this specific structure may be more effective than a ”human-thought” one.