Alexander E. MacDonald

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In recent years techniques have been developed to obtain integrated water vapor along slant paths between ground-based Global Positioning System (GPS) receivers and the GPS satellites. Results are presented of an observing system simulation (OSS) to determine whether three-dimensional water vapor fields could be recovered from a high-resolution network(More)
A survey of blind persons in Canada, based on registrations with The Canadian National Institute for the Blind (C.N.I.B.), is reported. This is the first study of its type having national scope and based on data registered in a central file. It covered 24,605 living registered blind persons ranging from premature infants to very elderly persons. Causes of(More)