This paper presents a complete dynamic analysis of roller and vane of a rotary compressor widely used for air-conditioners. An approach and a set of equations are developed estimating the type of motion at vane tip and roller interface and calculating the frictional force in accordance with the motion type. The forces on roller caused by relative motion between roller and cylinder wall are anal...

Roller skis are used by cross-country skiers, biathletes and ski-orienteers for their snow-free training and in roller ski competitions. Additionally, much of the current sports research into the physiology and biomechanics of crosscountry skiing is conducted indoors on treadmills using roller skis. For elite athletes, the differences in performance are quite small, thus emphasising the importa...

Reducing start and stop time without destroying the pavement surface is important in enhancing productivity of double-drum roller and compact quality of asphalt pavement, but it is difficult in confirming the maximum brake deceleration or start acceleration of double-drum roller. Dynamic analysis is used in studying these questions, and a mathematic model of double-drum roller is established, b...

More than 90% of Malaysian roads are constructed using asphaltic concrete. However, previous investigations of asphaltic concrete have mainly concentrated on the macroscopic properties of the composite materials based on the assumption that the mixtures are homogeneous and isotropic. This paper applies a digital image processing technique to compare the orientations of coarse aggregate particle...

OBJECTIVE To determine the number of fatalities related to roller coasters and examine factors common to multiple incidents. METHODS A case was defined as the death of a person, which was associated with a roller coaster in the United States between 15 May 1994 and 14 May 2004. Cases were identified from four DATA SOURCES (1) Consumer Product Safety Commission, (2) Lexis-Nexis, (3) Medline,...

The polymer solar cells were fabricated by a novel solution coating process, the roller painting. The roller painted film composed of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) has smoother surface than the spin coated film. Since the roller painting is accompanied with shear and normal stresses and is also a s low drying process, the process induces eff...

The first roller pump was patented in 1855 by Porter and Bradley and was hand operated. A modification first named "surgical pump", designed and manufactured by E. E. Allen in 1887, was intended for direct blood transfusion. Truax, who also distributed and promoted the Allen pump with one roller, developed the first double roller pump in 1899. In the following decades, several researchers, incl...

In an estuary, a tidal bore may be generated at the leading edge of the flood tidal wave during the early flood tide under spring tide conditions into a narrow funnelled channel. For Froude numbers greater than 1.4–1.6, the leading edge of the bore is characterised by a breaking roller. The roller is characterised by a sudden increase in water depth, a highly turbulent flow with large-scale vor...

The binary ink developer in the HP-Indigo press selectively applies condensed ElectroInk® onto the photoreceptor to form the image. The ink is transported by the elastomeric developer roller, which needs to be sufficiently conductive to allow its surface voltage remains constant as it moves through the various interfaces encountered along its periphery. But it cannot be so conductive as to disc...