A linear accelerator vendor and the AAPM TG-142 report propose that quality assurance testing for image-guided devices such megavoltage cone-beam CT (MV-CBCT) be conducted on a monthly basis. In clinical settings, however, unpredictable errors such as image artifacts can occur even when quality assurance results performed at this frequency are within tolerance limits. Here, we evaluated the ima...

In this paper, the problem of constructing geometric models from data provided by 3-D imaging sensors is addressed. Such techniques allow for rapid model-ing of sculptured free-form shapes and generation of geometric models for existing parts. In order for a complete data set to be obtained, multiple images, each from a diierent viewpoint, have to be merged. A technique stemming from the Iterat...

Solid modeling engines are capable of faceting CAD models but may facet each face independent of adjacent faces. Regions of the resulting model have gaps between faces of their boundaries. An algorithm is described to seal faceted CAD models such that the boundary of neighboring faces has the same discretization along their shared edges. The algorithm works by sealing skin edges of geometric fa...

The objective of tolerance analysis is to check the extent and nature of variation of an analyzed dimension or geometric feature of interest for a given GD & T scheme. The parametric approach to tolerance analysis is based on parametric constraint solving. The accuracy of simulation results is dependent on the user-defined modeling scheme. Once an accurate CAD model is developed, it is integrat...

in order to investigate the effect of water stress at heading stage on grain yield and yield components of eight wheat cultivars, in 2008 year a research was conducted in the two regions esfahan and ardestan by using split plot in a randomized complete block design with three replications which that two irrigation treatments included custom and late season water stress were main factor and 8 wh...

Numerous algorithms have been provided for maintaining the topology of a ring network in a fault-free environment. But a simple, fast and effective fault-tolerant algorithm has been lacking in this field so far. In this report, we seek to address this problem and provide a detailed design to solve the problem in the general case. As our detailed analysis proves, our algorithms function very wel...

Plants of six wheat varieties (Damani, Hashim-8, Gomal-8, DN-73, Zam-04, and Dera-98) were grown under three water regimes i.e. 100% Field Capacity (FC), 35% FC and 25% FC. Results of this experiment showed highly significant difference among wheat varieties in all the studied traits and water stress conditions decreased them significantly. The superior variety Hashim-8 which indicated higher r...

in order to evaluate the utilization ability of drought resistance indices such as: yield index (yi), yield stability index (ysi), stress susceptibility index (ssi), tolerance (tol), mean productivity (mp), geometric mean productivity (gmp) and stress tolerance index (sti) in sunflower hybrids, three separate experiments were conducted as randomized complete block design at the research field o...