Influence of PWM on the proximity loss in permanent magnet brushless AC machines

The winding copper loss can be significantly increased due to skin and proximity eddy current effects. The skin and proximity losses due to fundamental frequency current has been investigated in literature, but the influence of PWM on the skin and proximity losses has not been reported. In this paper, 2-D finite element method is employed to analyze the skin and proximity losses in a permanent magnet brushless AC machine, in which significant proximity loss exists due to high frequency current ripples induced by the PWM, as confirmed by both theoretical calculation and experiment. The analyses should be generally applicable to other machines

A new method of measuring shoulder hand behind back movement: Reliability, values in symptomatic and asymptomatic people, effect of hand dominance, and side-to-side variability

Shoulder hand behind back (HBB) range of motion (ROM) is a useful measure of impairment and treatment outcome. The purpose of this repeated measures study was to identify inter- and intra-rater reliability, of a new simplified method of measuring HBB ROM. Two experienced raters measured HBB ROM with a bubble inclinometer on 25 people (aged 42–75 years, 14 female) with unilateral shoulder dysfunction and 25 age- and gender-matched asymptomatic subjects on two different occasions. Statistical analysis included calculation of intra-class correlation coefficients (ICCs), minimal detectable change (MDC), standard error of measurement (SEM), Pearson correlation coefficient (r), coefficient of determination (R2), and the lower bound score. Mean HBB ROM was 108.6° (SD = 16.3) and 23.9° (SD = 10.5) on the pain-free and symptomatic side, respectively. Both intra-rater and inter-rater reliability were high (ICC > 0.80). For asymptomatic people the SEM was at most 3° and MDC was 8° with a strong correlation between the dominant and nondominant sides (r > 0.72). The mean absolute values and lower bound scores were at most 10.2° and 26.0°, respectively. These results indicate that this new and novel method of measuring HBB ROM is accurate, has good inter- and intra-rater reliability, and provides normal values for between-limb ROM variability

Development of dual energy X-ray absorptiometry to measure hand bone mineral content for the assessment of rheumatoid arthritis

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN013212 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

The nil Hecke ring and singularity of Schubert varieties

We give a criterion for smoothness of a point in any Schubert variety in any G/B in terms of the nil Hecke ring.Comment: AMSTE

GALEX J201337.6+092801: The lowest gravity subdwarf B pulsator

We present the recent discovery of a new subdwarf B variable (sdBV), with an exceptionally low surface gravity. Our spectroscopy of J20136+0928 places it at Teff = 32100 +/- 500, log(g) = 5.15 +/- 0.10, and log(He/H) = -2.8 +/- 0.1. With a magnitude of B = 12.0, it is the second brightest V361 Hya star ever found. Photometry from three different observatories reveals a temporal spectrum with eleven clearly detected periods in the range 376 to 566 s, and at least five more close to our detection limit. These periods are unusually long for the V361 Hya class of short-period sdBV pulsators, but not unreasonable for p- and g-modes close to the radial fundamental, given its low surface gravity. Of the ~50 short period sdB pulsators known to date, only a single one has been found to have comparable spectroscopic parameters to J20136+0928. This is the enigmatic high-amplitude pulsator V338 Ser, and we conclude that J20136+0928 is the second example of this rare subclass of sdB pulsators located well above the canonical extreme horizontal branch in the HR diagram.Comment: 5 pages, accepted for publication in ApJ Letter

Quantum Pieri rules for isotropic Grassmannians

We study the three point genus zero Gromov-Witten invariants on the Grassmannians which parametrize non-maximal isotropic subspaces in a vector space equipped with a nondegenerate symmetric or skew-symmetric form. We establish Pieri rules for the classical cohomology and the small quantum cohomology ring of these varieties, which give a combinatorial formula for the product of any Schubert class with certain special Schubert classes. We also give presentations of these rings, with integer coefficients, in terms of special Schubert class generators and relations.Comment: 59 pages, LaTeX, 6 figure

Mask formulas for cograssmannian Kazhdan-Lusztig polynomials

We give two contructions of sets of masks on cograssmannian permutations that can be used in Deodhar's formula for Kazhdan-Lusztig basis elements of the Iwahori-Hecke algebra. The constructions are respectively based on a formula of Lascoux-Schutzenberger and its geometric interpretation by Zelevinsky. The first construction relies on a basis of the Hecke algebra constructed from principal lower order ideals in Bruhat order and a translation of this basis into sets of masks. The second construction relies on an interpretation of masks as cells of the Bott-Samelson resolution. These constructions give distinct answers to a question of Deodhar.Comment: 43 page

Schubert calculus of Richardson varieties stable under spherical Levi subgroups

We observe that the expansion in the basis of Schubert cycles for $H^*(G/B)$ of the class of a Richardson variety stable under a spherical Levi subgroup is described by a theorem of Brion. Using this observation, along with a combinatorial model of the poset of certain symmetric subgroup orbit closures, we give positive combinatorial descriptions of certain Schubert structure constants on the full flag variety in type $A$. Namely, we describe $c_{u,v}^w$ when $u$ and $v$ are inverse to Grassmannian permutations with unique descents at $p$ and $q$, respectively. We offer some conjectures for similar rules in types $B$ and $D$, associated to Richardson varieties stable under spherical Levi subgroups of SO(2n+1,\C) and SO(2n,\C), respectively.Comment: Section 4 significantly shortened, and other minor changes made as suggested by referees. Final version, to appear in Journal of Algebraic Combinatoric

Effects of Supervised Exercise-based Telerehabilitation on Walk Test Performance and Quality of Life in Patients in India with Chronic Disease: Combatting COVID-19

Background: The world is currently undergoing a pandemic, caused by the SARS-CoV-2 virus (COVID-19). According to the World Health Organization, patients with chronic illnesses appear to be at the highest risk for COVID-19 associated sequelae. Inability to participate in outpatient-based rehabilitation programs and being home-bound can increase the risk for and potential worsening of chronic health conditions. This study evaluated the short-term effects of telerehabilitation on patients’ walk test performance and health related quality of life (HRQoL).  Methods: 47 patients (23 cardiovascular, 15 pulmonary, 9 oncology) participated in the telerehabilitation program. At baseline and following a 1-month intervention, patients had their 6-minute walk test distance (6MWTD) and HRQoL assessed. Average daily step counts were measured by the PACER App. Conclusion: Our results indicate that a short-term, supervised virtual telerehabilitation program had significant positive effects on 6MWTD and HRQoL in cardiac, pulmonary and oncology patients during COVID-19