The EXACT (EXact Area Coverage calculaTion) algorithm presented in this paper solves the Hidden Surface Elimination (HSE) problem on the subpixel level. The use of subpixel masks for anti-aliasing causes some problems with the HSE on the pixel level that are diicult to overcome. The approximations of the well known A-buuer algorithm are replaced by an exact solution that avoids erratic pixels a...

This paper introduces a new database of 25 recto/verso image pairs from documents suffering from bleed-through degradation, together with manually created foreground text masks. The structure and creation of the database is described, and three bleed-through restoration methods are compared in two ways; visually, and quantitatively using the ground truth masks.

We report the fabrication of large-area phase masks on thin fused-silica substrates that are suitable for shaping multiterawatt femtosecond laser beams. We apply these phase masks for the generation of intense femtosecond optical vortices. We further quantify distortions of the vortex beam patterns that result from several common types of mask defects.

This paper gives a brief survey of the design of masks for Hadamard spectrometers and image scanners. Three different criteria are described for judging a mask, as well as techniques for choosing masks that are not too far from the optimum.

In this paper, we introduce pressure masks for supporting the convenient abstraction of localized scale-specific point-like contact with a discrete elastic object. While these masks may be defined for any elastic model, special attention is given to the case of point-like contact with precomputed linear elastostatic models for purposes of haptic force-feedback.

The present study evaluated the efficacy of disposable surgical masks as a microbial barrier with 95% of Bacteria Filtration Efficacy (BFE) according to the wearing time (1, 2, 4 and 6 hours). The masks showed a decrease in efficacy after a 4-hour wearing time.

the use of masks, considering compliance with this advice unlikely because many Muslims believe that covering the face during the Hajj is prohibited and because masks need to be of high quality and changed at least every 6 hours to remain effective (7). Recent studies demonstrated that surgical and N95 masks were equally effective in preventing spread of PCR-detectable infl uenza virus when use...

In three experiments we tried to mask the motions of human gait. We represented human walkers as a set of 11 computer-generated elements on a display monitor, moving as a nested hierarchy of motions that mimicked the motions of the head and m~jor joints. The walker was seen in sagittal view, facing either right or let~ and walking as if on a treadmill. On the walker was superimposed a simultane...

BACKGROUND We compared the efficacy of medical masks, N95 respirators (fit tested and non fit tested), in health care workers (HCWs). METHODS A cluster randomized clinical trial (RCT) of 1441 HCWs in 15 Beijing hospitals was performed during the 2008/2009 winter. Participants wore masks or respirators during the entire work shift for 4 weeks. Outcomes included clinical respiratory illness (CR...

The standard coded aperture imaging approach assumes: • sources at infinity; • isolated point sources in specific directions; • masks with flat power spectrum (except for DC); • thin masks free of vignetting; • collimation to block rays from " out of view " directions; • visible sources cast full cycle of mask pattern on detectors; • use of correlation with the mask pattern to generate an image...