BACKGROUND Generally, attenuation correction is made by incorporating a linear attenuation coefficient, which is based on the attenuation coefficient map (mu-map) created from a computed tomography scan, into the ordered subsets-expectation maximization reconstruction method in non-uniform domains. A non-uniform Chang's attenuation correction method that uses the mu-map created from a computed ...

Aiming at the pulsation problem of traditional external grooved wheel fertilizer distributor, an opposed double spiral distributor is designed, and design analysis parameters are carried out. In order to obtain with best discharge effect, movement process particles in opposite was analyzed through discrete element simulation. Using combination simulation bench test, a orthogonal experiment out ...

Despite its wide application across arid land types, furrow irrigation is often associated with numerous environmental problems related to deep percolation, runoff, and soil erosion. In this study, a straightforward approach was proposed achieve higher uniformity reduce Here, the impacts that moveable “plug” has on behavior of water in were simulated using FLOW-3D HYDRUS-2D, where three plug he...

Pre-sowing treatment of seeds by plasma can improve seed vigor and promote germination growth. To solve the problems low processing volume uneven in devices, according to process scheme medium-blocking discharge treatment, a vibration-uniform material device was designed, structure working principle were systematically analyzed, mathematical model force established. According electromagnetic vi...

To improve the non-uniformity of a multi-cylinder marine diesel engine caused by manufacturing assembly errors and performance degradation fuel injection system, with instantaneous speed applied as control target, feedback variable each cylinder’s exhaust temperature was used to obtain information quantity cylinder variable; inhomogeneity accomplished modifying pulse spectrum. The model AVL Cru...

this research was conducted to study morphological and evaluation of genetic diversity of 15 grape cultivars in collections of agriculture and natural resources, research center of khorasan razavi based on completely randomized design with four replications. results showed extensive range of variations among cultivars and measured traits. in some key traits of tests for distinctness uniformity ...

Coating of particulate solids by a thin film layer is of interest in many industrial applications such as seed and tablet coating. In seed processing, seeds are commonly coated with a protective coating layer consisting of fertilisers and crop protection products. Rotary drum batch coaters are typically used for this purpose. The coater consists of a cylindrical vessel with a rotating spray dis...

(How and why to measure the germination process?). In the last two centuries, papers have been published including measurements of the germination process. High diversity of mathematical expressions has made comparisons between papers and some times the interpretation of results difficult. Thus, in this paper is included a review about measurements of the germination process, with an analysis o...