3,452 research outputs found
Goodness-of-Fit Tests to study the Gaussianity of the MAXIMA data
Goodness-of-Fit tests, including Smooth ones, are introduced and applied to
detect non-Gaussianity in Cosmic Microwave Background simulations. We study the
power of three different tests: the Shapiro-Francia test (1972), the
uncategorised smooth test developed by Rayner and Best(1990) and the Neyman's
Smooth Goodness-of-fit test for composite hypotheses (Thomas and Pierce 1979).
The Smooth Goodness-of-Fit tests are designed to be sensitive to the presence
of ``smooth'' deviations from a given distribution. We study the power of these
tests based on the discrimination between Gaussian and non-Gaussian
simulations. Non-Gaussian cases are simulated using the Edgeworth expansion and
assuming pixel-to-pixel independence. Results show these tests behave similarly
and are more powerful than tests directly based on cumulants of order 3, 4, 5
and 6. We have applied these tests to the released MAXIMA data. The applied
tests are built to be powerful against detecting deviations from univariate
Gaussianity. The Cholesky matrix corresponding to signal (based on an assumed
cosmological model) plus noise is used to decorrelate the observations previous
to the analysis. Results indicate that the MAXIMA data are compatible with
Gaussianity.Comment: MNRAS, in pres
A polarized beam splitter using an anisotropic medium slab
The propagation of electromagnetic waves in the anisotropic medium with a
single-sheeted hyperboloid dispersion relation is investigated. It is found
that in such an anisotropic medium E- and H-polarized waves have the same
dispersion relation, while E- and H-polarized waves exhibit opposite amphoteric
refraction characteristics. E- (or H-) polarized waves are positively refracted
whereas H- (or E-) polarized waves are negatively refracted at the interface
associated with the anisotropic medium. By suitably using the properties of
anomalous refraction in the anisotropic medium it is possible to realize a very
simple and very efficient beam splitter to route the light. It is shown that
the splitting angle and the splitting distance between E- and H- polarized beam
is the function of anisotropic parameters, incident angle and slab thickness.Comment: 14 pages, 6 figure
Improved effective mobility extraction in MOSFETs
The standard method of extracting carrier effective mobility from electrical measurements on MOSFETs is reviewed and the assumptions implicit in this method are discussed. A novel technique is suggested that corrects for the difference in drain bias during IV and CV measurements. It is further shown that the lateral field and diffusion corrections, which are both commonly neglected, in fact cancel. The effectiveness of the proposed technique is demonstrated by application to data measured on a quasi-planar SOI finFET at 300 K and 4 K
Rendezvous of Heterogeneous Mobile Agents in Edge-weighted Networks
We introduce a variant of the deterministic rendezvous problem for a pair of
heterogeneous agents operating in an undirected graph, which differ in the time
they require to traverse particular edges of the graph. Each agent knows the
complete topology of the graph and the initial positions of both agents. The
agent also knows its own traversal times for all of the edges of the graph, but
is unaware of the corresponding traversal times for the other agent. The goal
of the agents is to meet on an edge or a node of the graph. In this scenario,
we study the time required by the agents to meet, compared to the meeting time
in the offline scenario in which the agents have complete knowledge
about each others speed characteristics. When no additional assumptions are
made, we show that rendezvous in our model can be achieved after time in a -node graph, and that such time is essentially in some cases
the best possible. However, we prove that the rendezvous time can be reduced to
when the agents are allowed to exchange bits of
information at the start of the rendezvous process. We then show that under
some natural assumption about the traversal times of edges, the hardness of the
heterogeneous rendezvous problem can be substantially decreased, both in terms
of time required for rendezvous without communication, and the communication
complexity of achieving rendezvous in time
Designer requirements for visual capability loss simulator tools: Differences between design disciplines
There is a low uptake of inclusive design tools in industry, partly due to a poor fit between design tools and the thought and work processes of designers. Simulating visual capability losses is a technique with great potential in helping designers improve inclusivity and accessibility. However, we need to understand the needs of designers from different disciplines to improve the fit of these tools and their uptake in industry.
This study aims to determine designers’ needs for vision loss simulators, and how this varies between disciplines. Interviews were carried out with 15 designers from five disciplines. The results suggest that one tool is not suitable for all. The graphic and web designers interviewed required a tool to aid communication with clients, hoever, the industrial and engineering designers required two tools, depending on the stage of the design process. To increase their uptake, simulator tools should be used in education.We would like to thank the EPSRC for funding this work, and Wolfson College Cambridge for their support.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/978-3-319-07437-5_
Solitary wave solution to the generalized nonlinear Schrodinger equation for dispersive permittivity and permeability
We present a solitary wave solution of the generalized nonlinear Schrodinger
equation for dispersive permittivity and permeability using a scaling
transformation and coupled amplitude-phase formulation. We have considered the
third-order dispersion effect (TOD) into our model and show that soliton shift
may be suppressed in a negative index material by a judicious choice of the TOD
and self-steepening parameter.Comment: 6 page
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