BACKGROUND Lightweight portable oxygen systems are commonly preferred by patients over compressed-oxygen systems that use E-size cylinders. However, cost is often perceived as a barrier to the prescription of lightweight portable oxygen systems. OBJECTIVE To compare the overall health-care costs of patients with COPD who used lightweight portable oxygen systems to those who used E-cylinder sy...

Loading conditions and complex geometry have led the cylinder heads to become the most challenging parts of diesel engines. The aim of this study is to compare the distribution of temperature and stress in the aluminum and magnesium cylinder heads under thermo-mechanical loads. The three-dimensional model of the cylinder heads was simulated in abaqus software and a two-layer viscoplasticity mod...

'E now know, that, in the long bones of the human body, a portion of the bony cylinder may be deprived of the living principle; and that, in fuch cafes, nature gradually feparates the living from the dead part. While this feparation is taking place, a new cylinder is formed by an effufion of bony matter, fo as to inclofe the old bone, as it were, in a cafe ; and the new bone conneding itfelf wi...

Observations of the five confirmed optical pulsars indicate that the peak emission scales according to the magnetic field strength at the light cylinder. To the accuracy that such low number allows we show that this gives gives further confirmation that a straightforward synchrotron model such as Pacini & Salvati (1987) still has validity. The derived relationships indicates that the emission m...

The source is covered by a watertight steel cylinder which is fixed inside a 0.65 m long section of ASEA-ATOM type BWR fuel channel. Inside the cylinder there is a 37 GBq Cs pellet fixed to a wagon which can be driven up and down by means of a stepping motor. By moving the source, the repeatability of the geometrical positioning is attained. The amplitude and scanning speed are controlled by a ...

-A long circular cylinder with radius R and thickness t transmits a longitudinal eccentrically applied force to a rigid half-space. We study the influence of the eccentricity of the load and the ratio R/t on the stress state of the cylinder using the theory of thin shells in bending. The elastic displacements are presented in the form of a Fourier expansion, the coefficients of which are found ...

magnetic field effects on the elastic response of polymeric piezoelectric cylinder reinforced with carbon nanotubes (cnts) is studied. the cylinder is subjected to internal pressure, a constant electric potential difference at the inner and outer surfaces, thermal and magnetic fields. the mori-tanaka model is used for obtaining the equivalent material properties of the cylinder. based on the ch...

A helical relaxed plasma state is observed in a long cylindrical volume. The cylinder is long enough so that the predicted minimum energy state is a close approximation to the infinite cylinder solution. The plasma is injected at v ≥ 50 km/s by a coaxial magnetized plasma gun located at one end of the cylindrical volume. The relaxed state is rapidly attained in 1-2 axial Alfvén times after init...

This paper is based on portions of a keynote presentation, which explored the boundaries of what is understood about the vibration behavior of long cylinders excited by vortex shedding. The source of data is a recent field experiment on a long flexible cylinder, densely instrumented with fiber optic strain gauges. The paper emphasis is on previously unknown or unexplained phenomena and in some ...

Combined radiation and natural convection within the annular region of two infinitely long horizontal concentric cylinders are investigated numerically in this research. Radial and tangential radiation effects ate considered using Milne-Eddington approximation for a two-dimensional radiative transfer. The basic conservation equations are discretized with the finite volume method and SIMPLER alg...