The notion of upper distortion for graded submonoids embedded in groups and monoids is introduced. A finitely generated monoid M is graded if every element of M can be written in only finitely many ways in terms of some fixed system of generators. Examples of such monoids are free monoids, Artin monoids, and monoids satisfying certain small cancellation conditions. Whenever such a monoid is emb...

Given a semi-regular mesh whose subdivision onne tivity is obtained with the 4-8 s heme, we propose an algorithm to de ompose the mesh into a ontrol mesh and a series of embedded detail meshes. Hen e, the output representation is adaptive and progressive. We use a tree-driven, ne to oarse approa h to simplify the mesh using vertex de imation. Previous approa hes use lo al error and greedy strat...

During sintering a powder compact gains strength through low-temperature interparticle bonding, usually induced by solid-state surface diffusion, followed by further strength contributions from high-temperature densification. In cases where a liquid phase forms, sintering densification is accelerated and shape retention is sustained while open pores remain and contribute capillary forces. Unfor...

This paper presents an improved mathematical model for calculation of distortion vectors two aligned surface meshes. The shows better accuracy when benchmarked to existing with exceptional conditions, such as sharp corners and small radii. was implemented into a developed compensation digital tool applied industrial component. component made Inconel 718 produced by laser powder bed fusion 3D pr...

Custom high-resolution high-speed anterior segment spectral domain optical coherence tomography (OCT) was used to characterize three-dimensionally (3-D) the human crystalline lens in vivo. The system was provided with custom algorithms for denoising and segmentation of the images, as well as for fan (scanning) and optical (refraction) distortion correction, to provide fully quantitative images ...

The existing grid-based DEM has several disadvantages in representing the features of real terrain surface, such as peak clipping, channel filling, etc. And abrupt changes in elevation cannot be handled easily and precisely. The inherent size of grid mesh affects the DEM computing, analysis and results. Through the discussion of DEM terrain distortion, the representative types of distortion wer...

introduction echo-planar imaging (epi) is a group of fast data acquisition methods commonly used in fmri studies. it acquires multiple image lines in k-space after a single excitation, which leads to a very short scan time. a well-known problem with epi is that it is more sensitive to distortions due to the used encoding scheme. source of distortion is inhomogeneity in the static b0 field that ...

BACKGROUND Oral indomethacin causes villous shortening, microvascular damage, and distortion, which might induce mucosal ischaemia and necrosis. AIMS In order to determine the early events in indomethacin induced jejunal injury we examined the temporal relations between morphological damage and changes in villous blood flow following indomethacin. METHODS In anaesthetised rats, mid jejunal ...