An auto-focusing method in a digital image system is demonstrated that uses a standard deviation of pixel gray levels as a feedback signal. In this system, an optical microscope and a charge coupled device (CCD) camera are used to create clear pit images of optical discs. A dynamic focusing scheme is designed in the system-control software, which is able to eliminate environmental disturbances ...

Variable light focusing is the ability to flexibly select the focal distance of a lens. This feature presents technical challenges, but is significant for optical interrogation of three-dimensional objects. Numerous lens designs have been proposed to provide flexible light focusing, including zoom, fluid, and liquid-crystal lenses. Although these lenses are useful for macroscale applications, t...

In this paper, we introduce a new technique for wideband array processing. The new algorithm is based on the total least-square approach. The total least-square method is an alternative to the least-square method and uses the fact that the errors can exist both in the focusing location matrix and the estimated location matrix at the frequency bin. To prevent the focusing loss, we use a unitary ...

Numerical simulations are presented for ampholyte-based isoelectric focusing in 2D microgeometries. In this study, model proteins are focused in the presence of 25 biprotic ampholytes under an applied electric field. Each protein is considered as a simple polypeptide having ten charge states, while the biprotic ampholytes are selected to generate a shallow pH range of 6 to 9. Straight and contr...

Focusing waves inside a medium has applications in various science and engineering fields, e.g., in medicine, nondestructive evaluation, ocean acoustics, and geophysics. The goal in focusing is to concentrate the wave energy at a specific time and location inside a medium. Various techniques have been devised and used to achieve this goal. Time-reversal is a method that is routinely used to foc...

Isotropic optical focusing - the focusing of light with axial confinement that matches its lateral confinement, is important for a broad range of applications. Conventionally, such focusing is achieved by overlapping the focused beams from a pair of opposite-facing microscope objective lenses. However the exacting requirements for the alignment of the objective lenses and the method's relative ...

The smart city has become a popular topic of investigation. How to focus large amounts of distributed information resources to efficiently cope with public emergencies and provide support for personalized decision-making is a vitally important issue in the construction of smart cities. In this paper, an event-driven focusing service (EDFS) method that uses cyber-physical infrastructures for eme...

BioRad's Rotofor system has been frequently used for the purification of proteins and smaller peptides such as bacteriocins. In this study, we report that some commercially available ampholytes used with the Rotofor isoelectric focusing system possess antimicrobial activity, which may interfere with the purification of bacteriocins and bacteriocin-like substances.