Miracle-dz/UniFAR-FTUs huggingface dataset:
The repeated filamentation of two-dimensional vorticity interfaces

Undular disturbances of arbitrarily small steepness to the boundary of a circular patch of uniform vorticity are found to give way to a qualitatively different type of behaviour after a time inversely proportional to the initial wave steepness squared. Repeatedly, thin filaments are drawn out at a frequency of nearly half the vorticity jump across the interface (the intrinsic frequency of linear waves on the interface), and the interaction between the filaments and the undulating boundary generate new disturbances from which still greater numbers of filaments of increasingly complicated shape are drawn out. The vortex boundary thereby experiences an extraordinary, continual and apparently irreversible growth in complexity. Essentially the same phenomenon occurs on all vortex-patch equilibria, e.g. the Kirchhoff elliptical vortex, with even greater complexity. The steepening of a disturbance on a non-circular vortex proceeds faster than that on a circular vortex, because of the varying mean strain and shear seen by the disturbance as it travels around the vortex boundary. Generalizations to more than one vorticity interface, to flows on the surface of a sphere, and to sharp but not infinitely sharp vorticity gradients are also discussed. The results support the view that almost any two-dimensional, inviscid, incompressible flow with large vorticity gradients will exhibit repeated filamentation.
Genetic algorithm in the design of FIR filters

The author's aim is to describe a method of designing finite impulse response (FIR) filters that is automatic, rapid, and gives filter realisations of near minimal computational complexity. Existing methods of filter design are reviewed to show that none possesses all these features. These methods include recent work using a sequential algorithm that produces realisations of guaranteed minimum complexity and thus provides a reference for the results described in the paper. Genetic algorithms are described, and a method of representing the problem of filter synthesis for solution by a genetic algorithm is given. Results are presented, demonstrating the suitability of the genetic algorithm design method. >
On the characteristics of vortex filaments in isotropic turbulence

The statistical properties of the strong coherent vortices observed in numerical simulations of isotropic turbulence are studied. When compiled at axial vorticity levels ω/ω′∼Re1/2λ, where ω′ is the r.m.s. vorticity magnitude for the flow as a whole, they have radii of the order of the Kolmogorov scale and internal velocity differences of the order of the r.m.s. velocity of the flow u′. Theoretical arguments are given to explain these scalings. It is shown that the filaments are inhomogeneous Burgers' vortices driven by an axial stretching which behaves like the strain fluctuations of the background flow. It is suggested that they are the strongest members in a class of coherent objects, the weakest of which have radii of the order of the Taylor microscale, and indirect evidence is presented that they are unstable. A model is proposed in which this instability leads to a cascade of coherent filaments whose radii are below the dissipative scale of the flow as a whole. A family of such cascades separates the self-similar inertial range from the dissipative limit. At the vorticity level given above, the filaments occupy a volume fraction which scales as Re−2λ, and their total length increases as O(Reλ). The length of individual filaments scales as the integral length of the flow, but there is a shorter internal length of the order of the Taylor microscale.
Finite deformation of liquid capsules enclosed by elastic membranes in simple shear flow

The transient deformation of liquid capsules enclosed by elastic membranes subject to simple shear flow is studied numerically using a new implementation of the boundary element method. The numerical results for capsules with spherical unstressed shapes and varying degrees of surface elasticity are compared with the predictions of an asymptotic theory for small deformations due to Barthès-Biesel and coworkers, and the significance of nonlinear effects due to finite deformation is assessed. It is found that the capsules exhibit continuous elongation when the dimensionless shear rate becomes larger than a critical threshold, in agreement with recent experimental observations of capsules with polymerized interfaces. Membrane failure at large deformations is discussed with respect to membrane thinning and development of excessive elastic tensions, and it is argued that the location where the membrane is likely to rupture due to continued deformation is insensitive to the precise mechanism of rupture. The numerical results suggest that a dilute suspension of capsules behaves like shear-thinning medium with some elastic properties. Results of oblate spheroidal capsules suggest that the points of maximum membrane thinning and tension coincide but their location depends upon the unstressed capsule shape.
Free topological groups and dimension

For a completely regular space X we denote by F(X) and A(X) the free topological group of X and the free Abelian topological group of X, respectively, in the sense of Markov and Graev. Let X and Y be locally compact metric spaces with either A(X) topologically isomorphic to A(Y) or F(X) topologically isomorphic to F(Y). We show that in either case X and Y have the same weak inductive dimension. To prove these results we use a Fundamental Lemma which deals with the structure of the topology of F(X) and A(X). We give other results on the topology of F(X) and A(X) and on the position of X in F(X) and A(X).
Real and quasi-experiments in capture-recapture studies

The three key elements of experimental design are randomization, replication, and variance identification and control. Capture-recapture experiments usually pay sufficient attention to the first two elements, but often do not pay sufficient attention to sources of variation. These include blocking factors and different sizes of experimental units. By casting capture-recapture studies in an experimental design framework, the various roles of these sources of variation become clear and the sources that are pooled when these experiments are analysed using existing software is also clear. This formulation also shows that care must be taken with pseudo-replication and different sized experimental units.
Post-buckling Behavior of Beams Under Contact Constraints

An analytical model of the post-buckling behavior of a beam under contact constraints was derived. Experiments were carried out in order to characterize the various phenomenon involved in the problem. Two experiments with symmetric response with various contact surface and initial imperfection, and one experiment of asymmetric behavior were chosen for validation of the analytical results. The theory is based on a nonlinear kinematic approach and on the moving boundary procedure. The nonlinear equations are derived by the variational principle and solved through truncated approximating functions. A modification of an “arc-length” procedure was developed for solving the equation which incorporates the snapping effect. A comprehensive parametric study of the dominant parameters (distance between the beam and the contact surface, initial imperfections, contact location, magnitude of the contact forces, etc.) is carried out through numerical examples. Very good agreement with experimental results for the various phenomena involved in the problem was obtained for a clamped beam.
Variational difference method for elliptic problems with highly quasi-singular quadratic forms

To solve approximately elliptic problems [9] by the variational difference method, sufficient conditions for localization of singularities and quasi-singularities [7] of these problems were obtained in [4,5,6]. The original domain was assumed to be composed of subdomains in each of which the behaviour of the solution was determined by one of the model type behaviours studied in advance. The present paper is devoted to the construction of the best approximate solution (using the variational difference method) to two model elliptic boundary value problems with essentially different types of high quasi-singularity of the corresponding quadratic form. By the best approximate solution to the elliptic boundary value problem
Distribution inequalities for parallel models with unlimited capacity

Abstract Inequalities on reaction time distribution functions for n -channel parallel models with an unlimited capacity assumption are presented, extending previous work on serial models. First, the first-terminating and the exhaustive cases are considered without any assumption on the distribution functions. Later, certain general stochastic dependence properties are introduced, and appropriate distribution inequalities are derived and illustrated by specific parametric examples. Moreover, the inequalities are extended to finite mixture distributions and to censoring.
A ROSAT medium-sensitivity Galactic plane survey at 180°< l < 280°

We have performed a moderately deep soft X-ray ð0:1–2keVÞ survey of the Galactic plane using pointed observations with the ROSAT Position Sensitive Proportional Counter (PSPC). The survey is more than an order of magnitude more sensitive than previous X-ray surveys near the Galactic plane. The data consist of nine fields each of <10ks exposure, pointed at positions on or very close to the Galactic plane ðjbj , 08:3Þ in the longitude range 180 8& l & 2808. This region has relatively low X-ray absorbing material out to distances of several hundred pc and presents fewer source-confusion problems than at other longitudes. The total sky area surveyed was 2.5deg 2 ; this yielded 93 sources, 89 of which were detected in the ‘hard’ ð0:4–2:0keVÞ band. Nine sources were detected in both ‘soft’ ð0:1–0:4keVÞ and hard bands. In the hard band, the survey coverage is *90 per cent for sources brighter than 0.002counts 21 ð, 2 � 10 214 ergcm 22 s 21 Þ, but falls steeply below this value, with the weakest sources being ,0.001counts 21 . The median limiting flux is <0.0013counts 21 ð, 1:3 � 10 214 ergcm 22 s 21 Þ. There are 64 sources with hard-band count rates . 0.002counts 21 . We present the catalogue of X-ray sources and the number– flux relations ðlogN–logSÞ. Eighteen sources have possible identifications from the SIMBAD data base. We have searched the Tycho-2 and USNO-A2.0 catalogues to find all possible optical counterparts brighter than ,19th magnitude, and attempt to classify these on the basis of logðf X/foptÞ versus optical colour diagrams and near-infrared photometry from the 2MASS Second Incremental Data Release. Hence, we have found the majority of these sources to be consistent with being late-type main-sequence stars, as previous studies have proposed from incompletely identified surveys. Comparison of the measured number–flux relations with predictions of Galactic (stellar) and extragalactic populations supports the view that the population of young stars in the plane is denser than previously thought.
On the FIP Property for Extensions of Commutative Rings

ABSTRACT A (unital) extension R ⊆ T of (commutative) rings is said to have FIP (respectively be a minimal extension) if there are only finitely many (respectively no) rings S such that R ⊂ S ⊂ T. Transfer results for the FIP property for extensions of Nagata rings are obtained, including the following fact: if R ⊂ T is a (module-) finite minimal ring extension, then R(X)⊂T(X) also is a (module-) finite minimal ring extension. The assertion obtained by replacing “is a (module-) finite minimal ring extension” with “has FIP” is valid if R is an infinite field but invalid if R is a finite field. A generalization of the Primitive Element Theorem is obtained by characterizing, for any field (more generally, any artinian reduced ring) R, the ring extensions R ⊆ T which have FIP; and, if R is any field K, by describing all possible structures of the (necessarily minimal) ring extensions appearing in any maximal chain of intermediate rings between K and any such T. Transfer of the FIP and “minimal extension” properties is given for certain pullbacks, with applications to constructions such as CPI-extensions. Various sufficient conditions are given for a ring extension of the form R ⊆ R[u], with u a nilpotent element, to have or not have FIP. One such result states that if R is a residually finite integral domain that is not a field and u is a nilpotent element belonging to some ring extension of R, then R ⊆ R[u] has FIP if and only if (0 : u) ≠ 0. The rings R having only finitely many unital subrings are studied, with complete characterizations being obtained in the following cases: char(R)>0; R an integral domain of characteristic 0; and R a (module-)finite extension of ℤ which is not an integral domain. In particular, a ring of the last-mentioned type has only finitely many unital subrings if and only if (ℤ:R)≠0. Some results are also given for the residually FIP property.
The generation of a Tollmien-Schlichting wave by a sound wave

A spectral numerical method is used to study the two-dimensional unsteady flow over a flat plate in the presence of a plane sound wave propagating parallel to the flow. For s = ωx/U∞ > O(1), no observable interaction or energy interchange between the sound wave and the Tollmien-Schlichting wave is present. In the region s ≤ O(1), near the leading edge, an interaction occurs; the magnitude of this interaction is computed. A plane sound wave with dimensionless frequency ωv/U∞2 = 56 x 10-6 generates a Tollmien-Schlichting wave of the same frequency, and of amplitude, at the first neutral point, 10-4 of that of the sound wave. Computations at a second, lower frequency result in a smaller neutral point amplitude. The response of the boundary layer to large unsteady disturbances is discussed, and compared with published behaviour based on the boundary layer equations. Solutions of the Orr-Sommerfeld equation are examined and found to have a different character for s ≶ O(1), consistent with the more complete equations.
Small-Scale Spiral Bands Observed in Hurricanes Andrew, Hugo, and Erin

Abstract Analysis of radar data taken from the three intense hurricanes that passed close to WSR-57 and WSR-88D radar sites at their point of landfall illustrate small-scale spiral bands that are frequently observed within 100 km or so of the hurricane center. Faintly visible in the radar reflectivity images, these bands have scales of 10 km across the band and can extend for 100 km as they spiral outward in a clockwise fashion. They appear to move around the hurricane with speeds close to the tangential wind at the level of the bands and are characterized by enhanced updrafts with higher equivalent potential temperature in the regions of elevated reflectivity. They induce wind speed variations of at least 8 m s−1 across the bands. The authors suggest that these small-scale hurricane spiral bands are similar to boundary layer rolls although they extend through depths of 5–6 km, which is more than would be expected for rolls in the boundary layer near the sea. The data presented here are not sufficient to .
Improvement in calculation of the self- and mutual inductance of thin-wall solenoids and disk coils

The self-inductance expressions given by Yu and Han (1987) for air-core circular coils with rectangular cross sections, thin solenoids, and disk coils can be solved only by the numerical integration methods. We propose as an alternative a combined analytic and numeric approach. The approach brings some improvement in the calculations of self-inductance of thin-wall solenoids and disk coils that can be encountered in superconducting magnetic energy storage (SMES) problems. We also give a method for the calculation of mutual inductance of disk coils and of thin-wall solenoids. The results are obtained in an analytical form over the complete elliptic integrals of the first and second kind and Heuman's Lambda function. It is important to mention that the kernels of these integrals are always continuous functions on intervals of integration, so singularities are avoided. The results enable one to calculate the self-inductance and the mutual inductance of any thin air-core coil precisely and fast. For practical applications, the results are so simple to use that we recommend them to avoid the problems of solving the singular cases.
Assessing total quality management and its impact on product quality: A cross-sectional study on textile industries in Bandung, Indonesia

This study aims to predict the total quality management in medium to low-income companies in the textile industry in Bandung, Indonesia. The implementation of total quality management is one of the company's essential requirements. Previous studies indicate that the practice of quality management can improve the organizational performance in textile industry. We conducted a cross sectional survey study. The data is taken from the employees of textile industry. We made predictions using a non-parametric approach where the results of this study indicate several essential factors in implementing total quality management. This research is based on previous research studies that show the role of TQM in the textile industry and how it plays an essential role in the organization's success, especially in producing quality products. Moreover, the results of the study indicate that it is necessary to pay attention on the active role of management in quality improvement planning as it will improve the quality of products which is good for textile organization. Furthermore, this study examines the total quality management of low-income companies that fills the research gap.
LOWER LIMIT ON THE STRENGTH AND FILLING FACTOR OF EXTRAGALACTIC MAGNETIC FIELDS

High-energy photons from blazars can initiate electromagnetic pair cascades interacting with the extragalactic photon background. The charged component of such cascades is deflected and delayed by extragalactic magnetic fields (EGMFs), thereby reducing the observed point-like flux and potentially leading to multi-degree images in the GeV energy range. We calculate the fluence of 1ES 0229+200 as seen by Fermi-LAT for different EGMF profiles using a Monte Carlo simulation for the cascade development. The non-observation of 1ES 0229+200 by Fermi-LAT suggests that the EGMF fills at least 60% of space with fields stronger than G for lifetimes of TeV activity of yr. Thus, the (non-)observation of GeV extensions around TeV blazars probes the EGMF in voids and puts strong constraints on the origin of EGMFs: either EGMFs were generated in a space filling manner (e.g., primordially) or EGMFs produced locally (e.g., by galaxies) have to be efficiently transported to fill a significant volume fraction as, e.g., by galactic outflows.
Non-Diabetic Kidney Disease in Type 2 Diabetes Mellitus: A Changing Spectrum with Therapeutic Ascendancy

Background and objectives: Owing to changing epidemiology and therapeutic practices, a change in the spectrum of renal involvement in Type-2 diabetes mellitus (T2DM) has also been noted. The treatment of non-diabetic kidney disease (NDKD) differs from diabetic kidney disease (DKD) and the reversibility of NDKD in many cases to normal, prompts biopsy for rapid and accurate diagnosis. Data are scarce on kidney biopsy findings in T2DM. Study design & setting: In this observational study, we prospectively collected the data of kidney biopsies of patients aged ≥ 18 years with T2DM admitted between 1 August 2005 and 31 July 2022. The clinical, demographic and histopathological data were evaluated. The spectrum of kidney involvement in the form of DKD and/or NDKD was studied. The impact of these findings with the use of drugs retarding disease progression was also analyzed. Results: A total of 5485 biopsies were performed during the study period and of these 538 patients had T2DM. The mean age of the study population was 56.9 ± 11.5 years and 81% were males. The mean duration of DM was 6.4 ± 6.1 years. Diabetic retinopathy (DR) was noted in 29.7%. The most common indication for biopsy was an acute rise in creatinine (147, 27.3%). Amongst the 538 diabetic patients who underwent biopsy, histological features only of DKD were noted in 166 patients (33%), NDKD alone in 262 (49%) and NDKD with DKD lesions in 110 (20%). On multivariate analysis, duration of DM less than 5 years, absence of CAD, absence of DR, oliguria at presentation, an acute rise in creatinine and low C3 were associated with NDKD. Conclusions: The prevalence of NDKD among diabetics and ATIN in particular might be on an increasing trend in the current era of changing T2DM epidemiological patterns. The use of anti-pro-teinuric agents was associated with lesser degrees of histopathological chronicity in T2DM.
A Method for the Comparison of Item Selection Rules in Computerized Adaptive Testing

In a typical study comparing the relative efficiency of two item selection rules in computerized adaptive testing, the common result is that they simultaneously differ in accuracy and security, making it difficult to reach a conclusion on which is the more appropriate rule. This study proposes a strategy to conduct a global comparison of two or more selection rules. A plot showing the performance of each selection rule for several maximum exposure rates is obtained and the whole plot is compared with other rule plots. The strategy was applied in a simulation study with fixed-length CATs for the comparison of six item selection rules: the point Fisher information, Fisher information weighted by likelihood, Kullback-Leibler weighted by likelihood, maximum information stratification with blocking, progressive and proportional methods. Our results show that there is no optimal rule for any overlap value or root mean square error (RMSE). The fact that a rule, for a given level of overlap, has lower RMSE than another does not imply that this pattern holds for another overlap rate. A fair comparison of the rules requires extensive manipulation of the maximum exposure rates. The best methods were the Kullback-Leibler weighted by likelihood, the proportional method, and the maximum information stratification method with blocking.
Frail Multiple Myeloma Patients Deserve More Than Just a Score

Frailty is a hot topic in the field of multiple myeloma (MM). Clinicians have realised that frail myeloma patients can struggle with treatment, resulting in dose reductions and treatment discontinuation, which risk shorter progression-free and overall survival. Efforts have focused on the validity of existing frailty scores and on the development of new indices to identify frail patients more accurately. This review article explores the challenges of the existing frailty scores, including the International Myeloma Working Group (IMWG) frailty score, the revised Myeloma Co-morbidity Index (R-MCI), and the Myeloma Risk Profile (MRP). We conclude that the missing link is for frailty scoring to translate into a tool useful in real-world clinical practice. The future of frailty scores lies in their ability to be woven into clinical trials, to create a robust clinical evidence base for treatment selection and dose modification, and also to identify a cohort of patients who merit additional support from the wider MM multidisciplinary team.