631 research outputs found
Special asynchronous dynamometer designed for fast transient phenomena
This paper is focused on measurement of output of the rotary electromechanic machines, i.e. torque and speed.
Special attention is paid to the torque measurement under transient phenomena. The paper is also concentrated on the
optimization and interference of the designed asynchronous dynamometer. Thanks to the dynamometer it is possible to
measure very fast transient phenomena with a very high precision. The mathematical model of the asynchronous machine
completed with the mathematical description of the mechanical elements has also been added. Part of this work is focused on
parameters identification of the modeled mechanical elements. Selected transient states were simulated with the help of
MATLAB and SIMULINK language
A General Approach of Quasi-Exactly Solvable Schroedinger Equations
We construct a general algorithm generating the analytic eigenfunctions as
well as eigenvalues of one-dimensional stationary Schroedinger Hamiltonians.
Both exact and quasi-exact Hamiltonians enter our formalism but we focus on
quasi-exact interactions for which no such general approach has been considered
before. In particular we concentrate on a generalized sextic oscillator but
also on the Lame and the screened Coulomb potentials.Comment: 23 pages, no figur
Snail defence responses to parasite infection : the 'Lymnaea stagnalis-Trichobilharzia szidati' model
'Lymnaea stagnalis' is a common freshwater gastropod. Importantly, the snail serves as the intermediate host for more than one hundred species of digenetic trematodes, including the avian schistosome 'Trichobilharzia szidati', a causative agent of cercarial dermatitis in humans. Infection of 'L. stagnalis' by 'T. szidati' initiates a dynamic confrontation between the host and the parasite that culminates in immunocompatibility ensuring survival and development of larvae. Unfortunately, the molecular mechanisms determining this immunocompatibility remain poorly characterised. By employing a variety of immune elicitors, including chemical compounds, PAMPs and bacteria, research in the last two decades has elucidated some of the molecular processes that regulate the snail internal defence response such as haemocyte signalling pathways. These discoveries provide a framework for future studies of molecular interactions between 'T. szidati' and 'L. stagnalis' to help elucidate factors and mechanisms enabling transmission of schistosome parasites. Moreover, support from recently available next generation sequence data and CRISPR-enabled functional genomics should further enable 'L. stagnalis' as an important model for comparative immunology and contribute to a more comprehensive understanding of immune functions in gastropod molluscs
Measurement campaign on the JRC Ispra decommissioning site
The purpose of this document is to describe the measurement campaign with the Free Release Measurement Facility (FRMF) at building 41m “Interim Storage Facility” (ISF) of material clearable according to existing licenses as part of the collaborative research project MetroDecom.
The description of the measurement campaign includes the technical requirements and safety implementations necessary for carrying out this project.
The Free Release Measurement Facility (FRMF) was designed as a state of the art facility for measurement of low gamma-ray activity waste packages. Gamma spectrometric method for free release measurment was developed. The complemented with passive neutron counting method. The both methods are used for different nuclide contents in the waste and are complementary.
For this purpose the instrument incorporates:
— Three passive neutron counters (design of JRC)
— A gamma-ray detection system HPGe Interchangeable Detector Module IDM-200-V (ORTEC)
— NuDET Plastic Scintillation Detectors (design of NUVIA)
Decommissioning unit delivered seventy containers with material clearable according to existing JRC licenses. JRC G.II.7 performed the testing of the free release measurement system. The document contains the overview of that measurement campaign. The detailed measurement protocols, spectra generated by FRMF software are shared with MetroDecom Partners.JRC.G.II.7-Nuclear securit
Structure analysis of the Ga-stabilized GaAs(001)-c(8x2) surface at high temperatures
Structure of the Ga-stabilized GaAs(001)-c(8x2) surface has been studied
using rocking-curve analysis of reflection high-energy electron diffraction
(RHEED). The c(8x2) structure emerges at temperatures higher than 600C, but is
unstable with respect to the change to the (2x6)/(3x6) structure at lower
temperatures. Our RHEED rocking-curve analysis at high temperatures revealed
that the c(8x2) surface has the structure which is basically the same as that
recently proposed by Kumpf et al. [Phys. Rev. Lett. 86, 3586 (2001)]. We found
that the surface atomic configurations are locally fluctuated at high
temperatures without disturbing the c(8x2) periodicity.Comment: 14 pages, 4 figures, 1 tabl
In vivo fluorescence lifetime imaging of macrophage intracellular metabolism during wound responses in zebrafish
The function of macrophages in vitro is linked to their metabolic rewiring. However, macrophage metabolism remains poorly characterized in situ. Here, we used two-photon intensity and lifetime imaging of autofluorescent metabolic coenzymes, nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) and flavin adenine dinucleotide (FAD), to assess the metabolism of macrophages in the wound microenvironment. Inhibiting glycolysis reduced NAD(P)H mean lifetime and made the intracellular redox state of macrophages more oxidized, as indicated by reduced optical redox ratio. We found that TNFα+ macrophages had lower NAD(P)H mean lifetime and were more oxidized compared to TNFα− macrophages. Both infection and thermal injury induced a macrophage population with a more oxidized redox state in wounded tissues. Kinetic analysis detected temporal changes in the optical redox ratio during tissue repair, revealing a shift toward a more reduced redox state over time. Metformin reduced TNFα+ wound macrophages, made intracellular redox state more reduced and improved tissue repair. By contrast, depletion of STAT6 increased TNFα+ wound macrophages, made redox state more oxidized and impaired regeneration. Our findings suggest that autofluorescence of NAD(P)H and FAD is sensitive to dynamic changes in intracellular metabolism in tissues and can be used to probe the temporal and spatial regulation of macrophage metabolism during tissue damage and repair
Study of shock waves generation, hot electron production and role of parametric instabilities in an intensity regime relevant for the shock ignition
We present experimental results at intensities relevant to Shock Ignition
obtained at the sub-ns Prague Asterix Laser System in 2012 . We studied shock waves
produced by laser-matter interaction in presence of a pre-plasma. We used a first beam at
1ω (1315 nm) at 7 × 10 13 W/cm 2 to create a pre-plasma on the front side of the target and
a second at 3ω (438 nm) at ∼ 10 16 W/cm 2 to create the shock wave. Multilayer targets
composed of 25 (or 40 μm) of plastic (doped with Cl), 5 μm of Cu (for Kα diagnostics)
and 20 μm of Al for shock measurement were used. We used X-ray spectroscopy of Cl
to evaluate the plasma temperature, Kα imaging and spectroscopy to evaluate spatial and
spectral properties of the fast electrons and a streak camera for shock breakout measurements.
Parametric instabilities (Stimulated Raman Scattering, Stimulated Brillouin Scattering and
Two Plasmon Decay) were studied by collecting the back scattered light and analysing its
spectrum. Back scattered energy was measured with calorimeters. To evaluate the maximum
pressure reached in our experiment we performed hydro simulations with CHIC and DUED
codes. The maximum shock pressure generated in our experiment at the front side of the
target during laser-interaction is 90 Mbar. The conversion efficiency into hot electrons was
estimated to be of the order of ∼ 0.1% and their mean energy in the order ∼50 keV.
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distributio
Encodings of Range Maximum-Sum Segment Queries and Applications
Given an array A containing arbitrary (positive and negative) numbers, we
consider the problem of supporting range maximum-sum segment queries on A:
i.e., given an arbitrary range [i,j], return the subrange [i' ,j' ] \subseteq
[i,j] such that the sum of the numbers in A[i'..j'] is maximized. Chen and Chao
[Disc. App. Math. 2007] presented a data structure for this problem that
occupies {\Theta}(n) words, can be constructed in {\Theta}(n) time, and
supports queries in {\Theta}(1) time. Our first result is that if only the
indices [i',j'] are desired (rather than the maximum sum achieved in that
subrange), then it is possible to reduce the space to {\Theta}(n) bits,
regardless the numbers stored in A, while retaining the same construction and
query time. We also improve the best known space lower bound for any data
structure that supports range maximum-sum segment queries from n bits to
1.89113n - {\Theta}(lg n) bits, for sufficiently large values of n. Finally, we
provide a new application of this data structure which simplifies a previously
known linear time algorithm for finding k-covers: i.e., given an array A of n
numbers and a number k, find k disjoint subranges [i_1 ,j_1 ],...,[i_k ,j_k ],
such that the total sum of all the numbers in the subranges is maximized.Comment: 19 pages + 2 page appendix, 4 figures. A shortened version of this
paper will appear in CPM 201
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