17,457 research outputs found
Fourier Optics approach to imaging with sub-wavelength resolution through metal-dielectric multilayers
Metal-dielectric layered stacks for imaging with sub-wavelength resolution
are regarded as linear isoplanatic systems - a concept popular in Fourier
Optics and in scalar diffraction theory. In this context, a layered flat lens
is a one-dimensional spatial filter characterised by the point spread function.
However, depending on the model of the source, the definition of the point
spread function for multilayers with sub-wavelength resolution may be
formulated in several ways. Here, a distinction is made between a soft source
and hard electric or magnetic sources. Each of these definitions leads to a
different meaning of perfect imaging. It is shown that some simple
interpretations of the PSF, such as the relation of its width to the resolution
of the imaging system are ambiguous for the multilayers with sub-wavelenth
resolution. These differences must be observed in point spread function
engineering of layered systems with sub-wavelength sized PSF
Exploration and exploitation in the presence of network externalities
This paper examines the conditions under which exploration of a new, incompatible technologyis
conducive to firm growth in the presence of network externalities. In particular,
this studyis motivated bythe divergent evolutions of the PC and the workstation markets in
response to a new technology: reduced instruction set computing (RISC). In the PC market,
Intel has developed new microprocessors bymaintaining compatibilitywith the established
architecture, whereas it was radicallyr eplaced byRISC in the workstation market. History
indicates that unlike the PC market, the workstation market consisted of a large number
of power users, who are less sensitive to compatibilitythan ordinaryusers. Our numerical
analysis indicates that the exploration of a new, incompatible technologyis more likelyto
increase the chance of firm growth when there are a substantial number of power users or
when a new technologyis introduced before an established technologytakes off.
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Trigonometric vehicle guidance assembly which aligns the three perpendicular axes of two three-axes systems Patent
Electrical and electromechanical trigonometric computation assembly and space vehicle guidance system for aligning perpendicular axes of two sets of three-axes coordinate reference
Leading Groups To Create Healthy Culture Through Accomplishing Tasks Aligned To Strategy
This study examined the link between the consistency of self-evaluation versus peer-evaluation of managers’ skills and the level of relational stress in an organization and was based on two models: (a) the Competing Values Framework (CVF), which measures different management skills of individuals in an organization, and (b) the Healthy versus Toxic Organization Model, which focuses on the stress level in partnerships. The researchers hypothesized that the lower the stress in the organization, the more consistent the results will be between self-evaluation and peer-evaluation. In an empirical analysis, the researchers found that the relationship was most visible in the area of managers’ facilitator skills. With strong facilitator skills, managers can lead their organizations effectively and stay focused on maintaining strategic alignment. The study also examined how management skills could be most effective in developing a healthy work culture
Academic Achievement Differences by Student Mobility: An Analysis of Texas Grade 8 Student Performance
Differences in reading mathematics and science achievement of Grade 8 students as a function of mobility were examined with and without controls for economic status in this investigation Data were obtained from the Texas Education Agency Public Education Information Management System for the 2003-2004 through the 2007-2008 school years Statistically significant differences were revealed in reading mathematics and science test scores as a function of student mobility both when controlling for and not controlling for economic status Mobile students had statistically significantly lower reading and mathematics test scores than did non-mobile students for all 6 school years Science scores were statistically significantly lower for all three years for which data were available Implications for policy and practice and suggestions for future research were mad
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