Search results for "perimeter"
showing 6 items of 46 documents
Sobolev and bounded variation functions on metric measure spaces
2014
International audience
Perimeter leakage current in polymer light emitting diodes
2009
Observation of leakage current paths through the device perimeter in standard poly(phenylene vinylene)-based light-emitting devices is reported. Perimeter leakage currents govern the diode performance in reverse and low positive bias and exhibit an ohmic character. Current density correlates with the perimeter-to-area ratio thus indicating that leakage currents are mainly confined on polymer regions in the vicinity of metallic contact limits (device perimeter). © 2008 Elsevier B.V. All rights reserved.
Semigenerated Carnot algebras and applications to sub-Riemannian perimeter
2021
This paper contributes to the study of sets of finite intrinsic perimeter in Carnot groups. Our intent is to characterize in which groups the only sets with constant intrinsic normal are the vertical half-spaces. Our viewpoint is algebraic: such a phenomenon happens if and only if the semigroup generated by each horizontal half-space is a vertical half-space. We call semigenerated those Carnot groups with this property. For Carnot groups of nilpotency step 3 we provide a complete characterization of semigeneration in terms of whether such groups do not have any Engel-type quotients. Engel-type groups, which are introduced here, are the minimal (in terms of quotients) counterexamples. In add…
Experiments for testing soil texture effects on flow resistance in mobile bed rills
2018
Abstract In this paper a recently theoretically deduced rill flow resistance equation, based on a power-velocity profile, was tested experimentally on plots of varying slopes and soil texture in which mobile bed rills are incised. Measurements of flow velocity, water depth, cross section area, wetted perimeter and bed slope conducted in rill reaches incised on experimental plots, having different slope values (9, 14, 22, 24 and 26%) and soil texture (clay fraction ranging from 42 to 73%), and literature data were used to calibrate the flow resistance equation. In particular, the relationship between the velocity profile parameter Γ, the channel slope, the flow Froude number and texture frac…
Mindful Exercise (Baduanjin) as an Adjuvant Treatment for Older Adults (60 Years Old and Over) of Knee Osteoarthritis: A Randomized Controlled Trial
2020
Background. The postural stability is a major factor that helps prevent developing knee osteoarthritis with aging. The aim of this study was to investigate the effects of Baduanjin qigong on postural control and physical function in older adults with knee osteoarthritis. Methods. Fifty-six individuals over 60 years of age with knee osteoarthritis were randomly assigned to either an experimental group (n = 28) or a control group (n = 28). Participants in the experimental group received a 12-week Baduanjin training, while those in the control group did not receive any additional physical exercise during the study period. The postural control was quantified by perimeter and ellipse area of cen…
Optic neuropathy caused by type A botulinic toxin
2014
Purpose To report the development of an optical neuropathy after injection of type A botulinic toxin in a subject with blepharospasm. Methods Optical neuropathy was evaluated through a complete ophthalmologic examination consisting of bio-microscopy, tonometry and study of visual sharpness, colour test, visual field, OCT, fluorangiography and determination of VEPs. Results Intravenous therapy was begun with Metilprednisolone (20 mg/Kg/day) and Vitamin B6 associated with oral Citicoline, and there was a clear improvement down to normalization of the symptoms. After 6 months the Humphrey computerized visual field with central 30-2 program threshold test emphasised in ODx an upper half-field a…