nasoohi n 1 hoorizad m1 torabzadeh tari n 2   1- assistant prof, department of operative dentistry, islamic azad university, dental branch, tehran,iran   2-dentist   corresponding author : nasoohi n: department, no 4, 10th neyestan ave, pasdaran, tehran   tel : 09125392175 email: [email protected]     background and aim: discoloration of dental composites is one of the major reasons of the...

This paper presents a discussion on different techniques that can be used for the analysis of multispectral images (i.e., images taken in more than three spectral bands) that are acquired in the context of Cultural Heritage or Archaeological studies. False Color imaging, Blind Source Separation methods and techniques based on the use of Artificial Neural Networks are discussed. Examples are pre...

Background and Aim: The use of composite restorations has increased in recent years. One of the most important problems with composite restorations is the loss of consistency between the composite and tooth color, which in most cases requires replacement. Materials and Methods: In this study, the color stability of 40 disc-shaped specimens (10 mm in diameter and 2 mm in height) from two types ...

Color interpolation solutions drastically influence the quality of the whole image generation pipeline, so they must guarantee the rendering of high quality pictures avoiding typical artifacts such as blurring, zipper effects and false colors. Moreover, demosaicing should avoid emphasizing typical artifacts of real sensors data, such as noise and green imbalance effect, which would be further a...

Vision researchers base their work on assumptions that lenses behave ideally. In practice the image formation process is complex and camera lenses have many non-ideal behaviors that can cause problems in simple vision tasks like color image analysis and range from focus. For example, unlike the ideal lens the refractive power of a real lens is actually a function of wavelength. This means that ...

Composite resins were reinforced with glass and polyethylene fibers in this study, and the effect of fiber reinforcement on the color change of composite resins was investigated. After accelerated aging, the effect of fiber reinforcement on the color stability of composite resins was also examined. There were three experimental groups (n=12 disks per group): non-fiber-reinforced composite (non-...

introduction: diabetic retinopathy (dr) is one of the most serious and most frequent eye diseases in the world and the most common cause of blindness in adults between 20 and 60 years of age. following 15 years of diabetes, about 2% of the diabetic patients are blind and 10% suffer from vision impairment due to dr complications. this paper addresses the automatic detection of microaneurysms (ma...

This paper presents a robust face recognition method using color information with the following three-fold contributions. First, a novel hybrid color space, the RCrQ color space, is constructed out of three different color spaces: the RGB, Y CbCr, and Y IQ color spaces. The RCrQ hybrid color space, whose component images possess complementary characteristics, enhances the discriminating power f...

this study determined some spectral characteristics and relationship between landsat spectral reflectance and soil surface color in the arid region of iran (kashan). the study carried out in the kashan area that covers 90000 ha. consisting of mountain, hills and flood plain. enhanced thematic mapper (etm+) data collected on july 2002 were used for this research. the color composite images produ...