The present investigation is concerned with the coverage of the earth's surface by multiple-satellite
systems, taking into account results reported by Walker (1982). The considered …

Earlier studies of continuous whole-earth coverage by patterns of satellites in equal-period
circular orbits were extended by means of a computer program to patterns of up to 25 …

A study has been made of circular orbit patterns which ensure that every point on the earths
surface can always see at least one satellite or two satellites for double coverage above …

Background: Scleroderma is an autoimmune disorder of unknown cause. Previous epidemiological
studies have suggested some regional clustering and associations with occupations …

We reviewed literature on cognitive, sensory, motor and physical factors associated with
safe driving and crash risk in older adults with the goal of developing a model of factors …

Background People who inject drugs (PWID) are at increased risk for HIV and hepatitis C
virus (HCV) infection and also have high levels of homelessness and unstable housing. We …

Background People who inject drugs (PWID) experience a high prevalence of incarceration
and might be at high risk of HIV and hepatitis C virus (HCV) infection during or after …

A blind deconvolution algorithm based on the Richardson–Lucy deconvolution algorithm is
presented. Its performance in the presence of noise is found to be superior to that of other …

OBJECTIVE: To determine the incidence and severity of complications from laser in situ
keratomileusis (LASIK) for the correction of myopia by experienced and inexperienced surgeons…

THE association of hepatic cirrhosis with cyanosis and finger clubbing 1 2 3 4 and with arterial
oxygen desaturation 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 has been recognized …