Scheimpflug slit images of the crystalline lens are distorted due to the refracting properties of the cornea and because they are obliquely viewed. We measured the aspheric curvature of the lens of 102 subjects ranging in age between 16 and 65 years and applied correction for these distortions. The procedure was validated by measuring an artificial eye and pseudophakic patients with intraocular...

PURPOSE To estimate changes in surface shape and gradient refractive index (GRIN) profile in primate lenses as a function of accommodation. To quantify the contribution of surface shape and GRIN to spherical aberration changes with accommodation. METHODS Crystalline lenses from 15 cynomolgus monkeys were studied in vitro under different levels of accommodation produced by a stretching system....

In this paper, we propose equivalent radix-2 algorithms and evaluate them based on twiddle factor switching activity for a single delay feedback pipelined FFT architecture. These equivalent pipeline FFT algorithms have the same number of complex multipliers with the same resolution as the radix2. It is shown that the twiddle factor switching activity of the equivalent algorithms is reduced with...

Introduction: Micro-perforated absorbents are one of the structures that are widely used nowadays. The sound absorption mechanism is performed by viscous energy losses in the cavities on the plate. In this study, the acoustic properties of non-flat perforated panels in oblique angle was investigated in numerical method. Material and Methods: This paper examined the effect of the surface shape ...

Behavioural variability is likely to emerge when a particular task is performed in different cultural settings, assuming that part of human motor behaviour is influenced by culture. In analysing motor behaviour it is useful to distinguish how the action is performed from the result achieved. Does cultural environment lead to specific cultural motor skills? Are there differences between cultures...

anchusa )boraginaceae( includes weedy species in different habitats and cultivations and is composed of four species in iran. species delimitation is mainly based on features as zygomorphic or actinomorphic flowers, straight corolla tube and nutlet shape. in this project, morphological features of different accessions of anchusa species were evaluated. totally, 33 qualitative and quantitative m...

Otolith shape analysis is one way to identify stocks of different fish species in the marine environment. Length, width, area, perimeter, form factor, aspect ratio, roundness, circularity, ellipticity and rectangularity analyses of otoliths were undertaken to assess patterns of spatial and temporal stock structure of a wide-ranging fish, the Arabian yellow fin sea bream Acanthopagrus arabicus. ...

Results from previous studies suggest that two-dimensional spatial patterns are processed similarly in vision and touch when the patterns are equated for effective size or when visual stimuli are blurred to mimic the spatial filtering of the skin. In the present study, we measured subjects' ability to perceive the shape of familiar and unfamiliar visual and tactile patterns to compare form proc...

In this paper, we take a predefined geometry shape as a constraint for accurate shape alignment. A shape model is divided in two parts: fixed shape and active shape. The fixed shape is a user-predefined simple shape with only a few landmarks which can be easily and accurately located by machine or human. The active one is composed of many landmarks with complex shape contour. When searching an ...

This paper presents a novel elliptic shape defected ground structure (DGS) for low pass filter (LPF) applications. An equivalent RLC circuit model is presented and its corresponding parameters are also extracted from the measured S-parameters. The filter presents the advantages of compact size, high selectivity; low insertion loss and high out-band suppression from 5.15 GHz to 10 GHz below −31 ...