W hen the Internet Engineering Task Force approved Internet protocol version 6 several years ago, proponents acclaimed it as a major development. Since then, IPv6 (see the sidebar " IPv6 Primer ") has received support only in some areas. In Asia, for example, the profusion of smart cellular phones and PDAs has caused the demand for IP addresses to outstrip the limited supply provided by IPv4, t...

abstract background: correction of severe kyphosis is a challenging operation in spinal surgery. a two stage operation has been commonly used: anterior release and decompression followed by posterior correction and fusion. we describe the posterior vertebral osteotomy technique for correction of severe and rigid kyphosis through posterior-only approach. methods: twelve patients (six male and si...

land cover mapping is important for many planning and management activities. today, satellite images and remote sensing techniques are extensively used in all sectors including agriculture and natural resources because they provide updated data and high analyzing abilities. in this study, in order to produce land cover map for the northern part of hamedan province , digital satellite data irsp6...