Comisia Fulbright din Romania anunta deschiderea competitiei International Fulbright Science and Technology Award 2012, prin care se acorda studentilor, absolventilor si masteranzilor romani de la universitati de stat si private burse doctorale in domeniul ingineriei, tehnologiei si stiintelor exacte, la universitati de elita din Statele Unite ale Americii. Bursa vizeaza discipline precum: Aeronautica, Agronomie, Astronomie/Stiinte planetare, Biologie,

In this paper the non-linear process of light modulation performed by optical choppers is studied. The real functions of the transmitted flux, with transition portions are derived, in contrast to approximate approaches, of flux functions considered as series of rectangular impulses. An exact mathematical model of the dynamic phenomenon is thus achieved. Top-hat light beam distributions are considered. We are developing in this paper a new type of

We study different possible scanning functions of a galvanometer-based scanner (GS), considered with an optimal profile for the user, i.e., symmetrical, linear on their active portions, and with fast stop-and-turn parts. The scope is to obtain the function that provides the highest theoretical limit of the duty cycle of the device. From the equation of the oscillatory mirror, the active torque is obtained with regard to the scanning function. Several

CALL FOR SUBMISSIONS --SOCIETY FOR ROMANIAN STUDIES 2010 GRADUATE STUDENT ESSAY PRIZE The Society for Romanian Studies is pleased to announce the Second Annual Graduate Student Essay Prize competition for an outstanding unpublished essay or thesis chapter written in English by a graduate student in any social science or humanities discipline on a Romanian subject. The 2010 prize, consisting of $300, will be presented at the AAASS Convention in Los

Commisia Fulbright Romania-SUA anunta Programul International Fulbright Science and Technology 2011 pentru studii doctorale la universitati de top in domeniile stiintei, tehnologiei sau ingineriei. Candidatii pot fi absolventi de ciclu de licenta sau master, atat din universitati publice, cat si private. Durata finantarii: 3 years http://www.fulbright.ro/news/339-2010-international-fulbright-science-and-technology-award.html

We analyze the vignetting phenomenon both for optical systems with objects placed at finite distances and for systems with objects at infinity. Four of the possible definitions of the vignetting coefficient k, only two of them existing in the literature, are discussed. We propose two new definitions, i.e., a nonlinear geometric coefficient that is, in part, an analytical model of the vignetting characterization using optical software and a radiometric

The paper achieves the analysis and design of optical attenuators with double-prisms neutral density filters. A comparative study is performed on all the three possible device configurations, while only two of them are presented in literature, but without their designing calculus. The characteristic parameters of this optical attenuator with Risley translating prisms, for each of the three setups, are defined and their analytical expressions are

This study achieves a rigorous mathematical analysis of optical choppers, considered in their general constructive solution, with n symmetrical wings. Their characteristic parameters and functions are ascertained: the profile of the transmitted flux, the transmission coefficient, and the significant energetic relationships that result. Both aspects that may be used in optical systems are approached: the simplified case, of a light fascicle of small