The influence of non-imaging detector design on heralded ghost-imaging and ghost-diffraction examined using a triggered ICCD came

Ghost imaging and ghost diffraction can be realized by using the spatial correlations between signal and idler photons produced by spontaneous parametric down-conversion. If an object is placed in the signal (idler) path, the spatial correlations between the transmitted photons as measured by a single, non-imaging, “bucket” detector and a scanning detector placed in the idler (signal) path can reveal either the image or diffraction pattern of the object, whereas neither detector signal on its own can. The details of the bucket detector, such as its collection area and numerical aperture, set the number of transverse modes supported by the system. For ghost imaging these details are less important, affecting mostly the sampling time required to produce the image. For ghost diffraction, however, the bucket detector must be filtered to a single, spatially coherent mode. We examine this difference in behavour by using either a multi-mode or single-mode fibre to define the detection aperture. Furthermore, instead of a scanning detector we use a heralded camera so that the image or diffraction pattern produced can be measured across the full field of view. The importance of a single mode detection in the observation of ghost diffraction is equivalent to the need within a classical diffraction experiment to illuminate the aperture with a spatially coherent mode

MODIFICIRANO SPAJANJE JEDNOSTAVNIH SLIKA ZA PROSTORNU DOMENU

The aim of Image fusion is to combine the information from number of images of the same scene from different images with focus on different objects. The result of image is more informative and of better quality often the entropy content of the resultant image is poor due to improper local fusing. In this paper a comparative study and modified spatial domain approach is presented by fixing the contrast values of pixel in between the Average -minimum, and Average-Maximum to get better fusion capabilities. Experimental results demonstrates that the few of the proposed techniques outperform the existing techniques in terms of SNR and PSNR.Cilj fuzije slika je kombinirati podatke iz više fotografija iste scene sa raznih slika s naglaskom na različite objekte. Rezultat je slika koja je više informativna i kvalitetnija, ali često sadržajno entropija finalne slike je slaba zbog nepravilnog lokalne fuzije. U ovom radu provedeno je komparativno istraživanje i pristup modificiranja prostorne domene, predstavljeno kroz učvršćivanje kontrasta vrijednosti piksela između prosječnog minimalnog i prosječno maksimalnog da bi dobili bolje fuzijske karakteristike. Eksperimentalni rezultati pokazuju da neke od predloženih tehnika nadmašuju postojeće tehnike u smislu SNR i PSNR

A Framework for Participatory Impact Assessment: involving stakeholders in European policy making, a case study of land use change in Malta

A Framework for Participatory Impact Assessment is presented for use within European land use policy impact assessment. The context and rationale for the development of the Framework are outlined, both in the context of European policy making and within a project called "Sustainability Impact Assessment: Tools for Environmental, Social and Economic Effects of Multifunctional Land Use in European Regions". A detailed description of the sequence of methods that make up the Framework is provided, followed by illustrations and details of the practical application and results from a case study in Malta, where the Framework was used to carry out an impact assessment of biodiversity policies. After reporting on the reflections of the research team and valuable feedback provided by Maltese stakeholders, the Framework’s ability to enhance the quality, credibility and legitimacy of European policy impact assessment is discusse

Midinfrared third-harmonic generation from macroscopically aligned ultralong single-wall carbon nanotubes

We report the observation of strong third-harmonic generation from a macroscopic array of aligned ultralong single-wall carbon nanotubes (SWCNTs)with intensemidinfrared radiation. Through power-dependent experiments, we determined the absolute value of the third-order nonlinear optical susceptibility !(3) of our SWCNT film to be 5.53 × 10−12 esu, three orders of magnitude larger than that of the fused silica reference we used. Taking account of the filling factor of 8.75% for our SWCNT film, we estimate a !(3) of 6.32 × 10−11 esu for a fully dense film. Furthermore, through polarization-dependent experiments, we extracted all the nonzero elements of the !(3) tensor, determining the magnitude of the weaker tensor elements to be #1/6 of that of the dominant !(3) zzzz component

Combined numerical and experimental investigation of surface textured journal bearings [Abstract]

Combined numerical and experimental investigation of surface textured journal bearings [Abstract

Isotope effects and possible pairing mechanism in optimally doped cuprate superconductors

We have studied the oxygen-isotope effects on T_{c} and in-plane penetration depth \lambda_{ab}(0) in an optimally doped 3-layer cuprate Bi_{1.6}Pb_{0.4}Sr_{2}Ca_{2}Cu_{3}O_{10+y} (T_{c} \sim 107 K). We find a small oxygen-isotope effect on T_{c} (\alpha_{O} = 0.019), and a substantial effect on \lambda_{ab} (0) (\Delta \lambda_{ab} (0)/\lambda_{ab} (0) = 2.5\pm0.5%). The present results along with the previously observed isotope effects in single-layer and double-layer cuprates indicate that the isotope exponent \alpha_{O} in optimally doped cuprates is small while the isotope effect on the in-plane effective supercarrier mass is substantial and nearly independent of the number of the CuO_{2} layers. A plausible pairing mechanism is proposed to explain the isotope effects, high-T_{c} superconductivity and tunneling spectra in a consistent way.Comment: 5 pages, 4 figure

Effective Action for the Quark-Meson Model

The scale dependence of an effective average action for mesons and quarks is described by a nonperturbative flow equation. The running couplings lead to spontaneous chiral symmetry breaking. We argue that for strong Yukawa coupling between quarks and mesons the low momentum physics is essentially determined by infrared fixed points. This allows us to establish relations between various parameters related to the meson potential. The results for $f_\pi$ and \VEV{\olpsi\psi} are not very sensitive to the poorly known details of the quark--meson effective action at scales where the mesonic bound states form. For realistic constituent quark masses we find $f_\pi$ around 100\MeV.Comment: 56 pages (including 10 figures and 1 table), uses epsf.st