Search results for "DWI"
showing 10 items of 529 documents
Design of double-tapered fibers for tailoring the acousto-optic spectral response
2016
A model to shape the spectral response of acousto-optic devices based on tapered fibers is reported. A double-tapered structure was designed in order to obtain a flat attenuation response with 34 nm bandwidth.
Scene-based spectral calibration assessment of high spectral resolution imaging spectrometers
2009
An accurate knowledge of the spectral calibration of imaging spectrometers is required for optimum data processing and interpretation. The scene-based spectral characterization of imaging spectrometers is frequently necessary to update or replace the pre-flight laboratory-based spectral characterization supplied by the data provider. An automatic method for the estimation of spectral calibration parameters (channel position and bandwidth) at atmospheric absorption regions from high spectral resolution imaging spectrometers (spectral sampling interval below 5 nm) is presented in this contribution. The method has been tested on two commercial instruments with spectral sampling intervals below…
FDTD analysis of E-sectoral horn antennas for broad-band applications
1997
The finite-difference time-domain (FDTD) method is applied to study the performance of E-plane sectoral horn antennas designed for broad-band applications. These antennas (proposed for 6-18 GHz phased arrays) have a large bandwidth, and they are easily array integrated. These antennas have a highly complicated geometry that is modeled using a polygonal approximation in the curved boundaries. Perfect matched layers (PMLs) combined with first-order absorbing boundaries are employed to simulate the free-space environment in the FDTD mesh.
User bandwidth usage-driven HNN neuron excitation method for maximum resource utilization within packet-switched communication networks
2006
Mobile and wireless systems beyond 3G are being designed under the user-centric paradigm. Dynamic resource allocation (DRA) is a topic on intensive research to address efficiently such paradigm. Hopfield neural networks (HNN) have proved useful in the past to solve this kind of complex optimization problems. Recently, various approaches have been proposed to realize HNN-based user-centric DRA. However, the initial algorithms suffer from severe instability problems impacting the overall performance. This letter analyses the source of the existing limitations and proposes an enhanced formulation, ensuring maximum resource utilization while optimizing the convergence of the neural network. The…
Risonanza magnetica DWI nei pazienti affetti da Orbitopatia di Graves.
2015
Brief an Garlieb H. Merkel
1799
Ms. 930a, Nr. 8, Bl. 22r-23v Böttiger, Karl August. Brief an Garlieb H. Merkel, Weimar, d[en] 13. November 1797 Autora rokraksts / Autograph, vācu, angļu un latīņu val. / Deutsch, Englisch und Latein [4] lpp. / S. Attēlu numuri / Bildnummern: 930a-008-1 – 930a-008-4 Der Verfasser nennt in diesem inhaltsreichen Brief zahlreiche Namen und hält nicht nur die Verbindung mit Merkel, die aus dessen erstem Aufenthalt in Weimar resultierte, aufrecht, sondern gibt ihm weitere Hinweise und Empfehlung für seinen weiteren Aufenthalt in Dänemark. So rät er zur Übersetzung dreier Romane aus dem Englischen, darunter Jane Wests „A gossip's story“ (London 1796). Ferner bittet der Verfasser Merkel um Gefälli…
White light sources filtered with fiber Bragg gratings for RF-photonics applications
2003
Abstract In this paper we demonstrate that broadband light emitters filtered with fiber Bragg gratings are a suitable light source for RF-photonics applications. A 0.075 nm bandwidth fiber grating illuminated by a light emitter of 40 nm bandwidth has been used as light source to feed a microwave phase shifter based on a chirped fiber Bragg grating. The device operates successfully in the tested frequency range (0.5–6) GHz and has been optically tuned in a range of 4 nm.
Misión FLEX (Fluorescence Explorer): Observación de la fluorescencia por teledetección como nueva técnica de estudio del estado de la vegetación terr…
2014
[EN] FLEX (Fluorescence EXplorer) is a candidate for the 8th ESA’s Earth Explorer mission. Is the first space mission specifically designed for the estimation of vegetation fluorescence on a global scale. The mission is proposed to fly in tandem with the future ESA´s Sentinel-3 satellite. It is foreseen that the information obtained by Sentinel-3 will be supplemented with that provided by FLORIS (Fluorescence Imaging Spectrometer) onboard FLEX. FLORIS will measure the radiance between 500 and 800 nm with a bandwidth between 0.1 nm and 2 nm, providing images with a 150 km swath and 300 m pixel size. This information will allow a detailed monitoring of vegetation dynamics, by improving the me…
Minimal invasive Therapie bei peritonealer Leiomyomatose
1994
Leiomyomatosis peritonealis disseminata (LPD) is a rare benign disease characterised by the presence of multiple intraabdominal nodules, consisting of benign smooth muscle. LPD has only been found in women, predominantly in their late reproductive age. There is a very high association with excess exogenous and endogenous female gonadal steroids, specifically oestrogen and progesterone. Since it is grossly indistinguishable from diffuse carcinomatosis of the peritoneum, several unnecessary radical procedures have resulted. We describe the 44th documented case and the first case of minimal invasive surgery in a 42-year-old women with peritoneal leiomyoma on the right pelvic wall and uterine s…