Videokeratometers and Scheimpflug cameras permit accurate estimation of corneal surfaces. From height data it is possible to adjust analytical surfaces that will be later used for aberration calculation. Zernike polynomials are often used as adjusting polynomials, but they have shown…

In this paper we analyze a simple experiment to study the effects of polarized light. A simple optical system composed of a polarizer, a retarder (cellotape) and an analyzer is used to study the effect on the polarization state of…

This paper presents a multilayered architecture that enhances the capabilities of current QA systems and allows different types of complex questions or queries to be processed. The answers to these questions need to be gathered from factual information scattered throughout…

Despite growing evidence that participation in out-of-school activities and especially physical activity and sport programs facilitates positive development, little developmental research has been conducted on out-of-school sports programs compared with no participation in these activities or participation in other activities.…

The purpose of this investigation is to evaluate whether or not the allocation of time proposed in the Music Study Guide, adapted from the European Higher Education Area (EHEA) guidelines, is consistent and adequate for students with minimal musical knowledge.…

An analytical approximate procedure for a class of conservative single degree-of-freedom nonlinear oscillators with odd non-linearity is proposed. This technique is based on the generalized harmonic balance method in which analytical approximate solutions have rational forms. Unlike the classical harmonic…

The analytical approximate technique developed by Wu et al for conservative oscillators with odd nonlinearity is used to construct approximate frequency-amplitude relations and periodic solutions to the dynamically shifted oscillator. This nonlinear oscillator is described by an equation of motion…

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The Chinese tourism sector is experiencing one of the highest levels of growth, to the extent that China is set to become the leading world power in tourism within the coming decade. Therefore, studying this important sector deserves particular attention.…

The ntcA gene from Synechococcus sp. strain PCC 7942 encodes a regulatory protein which is required for the expression of all of the genes known to be subject to repression by ammonium in that cyanobacterium. Homologs to ntcA have now…