Search results for "Sound"
showing 10 items of 1845 documents
Highly stable Zerodur based optical benches for microgravity applications and other adverse environments
2019
A number of cold atom experiments are restrained by the impeding effects of gravity. While efforts have been made to overcome these limitations in a gravitational environment, another approach is placing the experiment in a microgravity environment, as can be found aboard sounding rockets, satellites or a space station. The cornerstone of such experiments is a robust laser system. The adverse conditions during a rocket launch impose stringent requirements on thermal stability and resilience against mechanical stress on this part of the experimental setup. Furthermore, the very limited space found on any of the aforementioned microgravity platforms necessitates maximal miniaturization. In or…
KernelICA : Kernel Independent Component Analysis
2021
The kernel independent component analysis (kernel ICA) method introduced by Bach and Jordan (2003) . The incomplete Cholesky decomposition used in kernel ICA is provided as separate function. nonPeerReviewed
Using deep learning to generate synthetic B-mode musculoskeletal ultrasound images
2020
Background and objective\ud Deep learning approaches are common in image processing, but often rely on supervised learning, which requires a large volume of training images, usually accompanied by hand-crafted labels. As labelled data are often not available, it would be desirable to develop methods that allow such data to be compiled automatically. In this study, we used a Generative Adversarial Network (GAN) to generate realistic B-mode musculoskeletal ultrasound images, and tested the suitability of two automated labelling approaches.\ud \ud Methods\ud We used a model including two GANs each trained to transfer an image from one domain to another. The two inputs were a set of 100 longitu…
Sonographie bei Skelettmetastasen - Stellenwert im Vergleich zur Computertomographie und konventionellen Röntgendiagnostik
1990
The value of CT, conventional radiography and ultrasound was compared in 40 patients with 52 skeletal metastases. For superficial lesions, the combination of sonography and conventional radiography was equivalent to CT in showing the extent of bone destruction and soft tissue involvement. As expected sonography was unsatisfactory for deeper lesions. Sonography can provide useful information for planning radiation therapy for superficial lesions, but it does not replace conventional radiography.
Ten years of measured UV Index from the Spanish UVB Radiometric Network.
2013
An analysis is made of the UV Index (UVI) obtained from the ultraviolet erythemal solar radiation (UVER) data measured by the Spanish UVB Radiometric Network between the years 2000 and 2009. Previously, the daily UVI has been evaluated using two different criteria: (a) the value corresponding to solar noon; and (b) the daily maximum value. The mean percentage of agreement is 92% if we consider the cases for which the difference is zero or one UVI unit. These results are similar to those obtained in a previous work where only 2 years were analyzed. In all the stations the UVI reaches very high values (8-10) in spring-summer, and the very high and extreme (≥ 11) UVI values are more dependent …
Glow Rate Technique for Spectroscopy of Complex Thermostimulated Relaxation Processes
1996
The glow rate technique (GRT) developed for the analysis of complex trap spectra, is the extension of the known heating rate method to the full glow curve. It is shown that using two glow curves measured at different heating rate constants, a special mean activation energy of simultaneously emptied traps can be obtained as a function of temperature or emitted light sum to a good approximation. Expressions have been derived for the calculation of the mean activation energy function from data measured using a linear, logarithmic or a hyperbolic heating mode. Theoretical expressions for the mean activation energy function have been obtained and discussed for arbitrary trap distribution functio…
Isolation and characterization of a photosystem I-associated antenna (LHC I) and a photosystem I—core complex from the chlorophyll c-containing alga …
1993
Abstract A photosystem (PS) I holocomplex was isolated from Pleurochloris meiringensis Vischer (Xanthophyceae) using sucrose density centrifugation. This complex exhibited a fluorescence emission maximum at 715 nm, which is in accordance with the long wavelength emission of whole cells. The complex was further dissociated into a core complex and a light-harvesting protein (LHC I). The core protein contains mainly Chl a and β-carotene, is 8.25 times enriched in P700 and has its main emission maximum at 715 nm. Therefore, the longest wavelength emission of P. meiringensis is due to the PS I core, which is in contrast to higher plants. The LHC I differs from LHC II with regard to its polypepti…
Role of ΔpH in the mechanism of zeaxanthin-dependent amplification of qE
1995
Abstract The influence of zeaxanthin on the high-energy-state fluorescence quenching (qE) and the pH dependence of the maximum chlorophyll fluorescence yield (Fm) was examined in spinach thylakoids. High contents of zeaxanthin were achieved using different pretreatments. A pronounced, zeaxanthin-dependent amplification of non-photochemical quenching (NPQ) was exclusively found in thylakoids containing zeaxanthin, synthesized in the dark via the buildup of an artificial ΔpH. These thylakoids also showed a significant quenching of chlorophyll fluorescence in the range pH 5.5–6.3, where no or only slight quenching was visible in zeaxanthin-free thylakoids. Thylakoids containing high amounts of…
A Preliminary Estimation of the Direct Ultraviolet Spectral Irradiance in Valencia (Spain): Comparison with Measured Values
2000
UVSPEC and SMARTS2 models have been used to estimate the UV spectral irradiance values in Valencia, Spain, and the results of these estimations have been compared with experimental measurements of direct irradiance at normal incidence obtained using an Optronic OL 754 in the 300-400 nm range. The relative RMSD and MBD parameters have been used to estimate the deviations of the modelled values with respect to the experimental values. The results indicate that the deviations are smaller when the SMARTS2 model is used with the appropriate aerosol coefficients.
Radical scavenging activity of ultrasound-treated Carbon Nanotubes
2016
Carbon nanotubes (CNTs) having controlled radical activity have been achieved tuning the content of their lattice defects induced by an ultra-sound (us) treatment.