15 research outputs found
Direction dependent Point spread function reconstruction for Multi-Conjugate Adaptive Optics on Giant Segmented Mirror Telescopes
Modern Giant Segmented Mirror Telescopes (GSMT) like the Extremely Large
Telescope (ELT), currently under construction depend heavily on Adaptive Optics
(AO) systems to correct for atmospheric turbulence. To be able to correct wider
fields of view (FoV), Multi-Conjugate Adaptive Optics (MCAO) systems were
introduced, which use multiple guide stars to obtain an almost uniform
correction over the FoV. However, a residual blur remains in the astronmical
images due to the time delay stemming from the wavefront sensor (WFS)
integration time and temporal response of the deformable mirror(s) (DM). This
results in a blur which can be mathematically described by a convolution of the
true image with the point spread function (PSF). Due to the nature of the
atmosphere and its correction, the PSF is spatially varying.
In this paper, we present an algorithm for MCAO PSF reconstruction adapted to
the needs of GSMTs in a storage efficient way. In particular, the PSF
reconstruction algorithm for Single Conjugate Adaptive Optics (SCAO) from [40]
is combined with an algorithm for atmospheric tomography from [33] to obtain a
direction dependent reconstruction of the post-AO PSF.
Results obtained in an end-to-end simulation tool show qualitatively good
reconstruction of the PSF compared to the PSF calculated directly from the
simulated incoming wavefront. Furthermore, the used algorithm has a reasonable
runtime and memory consumption.Comment: submitted for publicatio
Helicopter nonlinear flight control system development
SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Helicopter nonlinear flight control system development
SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman
Calculation of trim settings for a helicopter rotor by an optimized automatic controller
Oscillatory behaviors in initial film boiling: Implications on the triggerability of single droplet vapor explosions
SCREENING THE RELOCATION STRATEGIES OF WATER QUALITY MONITORING STATIONS BY COMPROMISE PROGRAMMING
Water quality monitoring network designs historically have tended to use experience, intuition, and subjective judgment in siting monitoring stations only sporadically. Better design procedures for optimizing monitoring systems with respect to multiple criteria decision analysis had rarely been put into practice up front when the needs for intensive monitoring became critical. This paper describes a systematic relocation strategy that is organized to identify several significant planning objectives and consider a series of inherent constraints simultaneously. The planning objectives considered in this analysis are designed to enhance the detection possibility for lower compliance areas, reflect the emphasis for different attainable water uses at different locations, promote the potential detection for the lower degradation areas of pollutants, increase the protection degree of those areas with higher population density in the proximity of the river system, and strengthen the pre-warning capability of water quality for water intakes. The constraint set contains the limitations of budget, the equity implication, and the detection sensitivity in the water environment. A case study in the Kao-Ping River Basin, South Taiwan, demonstrates the application potential of this methodology based on a seamless integration between the optimization and the simulation models. It enables identification of the optimal locational pattern stepwise using the embedded screening and sequencing capacity in a compromise programming model. However, a well calibrated and verified water quality model is an indispensable tool in support of this multiobjective evaluation. Extra sampling procedures become necessary for the sites with sparse environmental information. Comparison of planning outcomes of compromise programming is made against previously achieved analyses by using weighted programming and fuzzy programming
Mutations in multiple components of the nuclear pore complex cause nephrotic syndrome
Item does not contain fulltextSteroid-resistant nephrotic syndrome (SRNS) almost invariably progresses to end-stage renal disease. Although more than 50 monogenic causes of SRNS have been described, a large proportion of SRNS remains unexplained. Recently, it was discovered that mutations of NUP93 and NUP205, encoding 2 proteins of the inner ring subunit of the nuclear pore complex (NPC), cause SRNS. Here, we describe mutations in genes encoding 4 components of the outer rings of the NPC, namely NUP107, NUP85, NUP133, and NUP160, in 13 families with SRNS. Using coimmunoprecipitation experiments, we showed that certain pathogenic alleles weakened the interaction between neighboring NPC subunits. We demonstrated that morpholino knockdown of nup107, nup85, or nup133 in Xenopus disrupted glomerulogenesis. Re-expression of WT mRNA, but not of mRNA reflecting mutations from SRNS patients, mitigated this phenotype. We furthermore found that CRISPR/Cas9 knockout of NUP107, NUP85, or NUP133 in podocytes activated Cdc42, an important effector of SRNS pathogenesis. CRISPR/Cas9 knockout of nup107 or nup85 in zebrafish caused developmental anomalies and early lethality. In contrast, an in-frame mutation of nup107 did not affect survival, thus mimicking the allelic effects seen in humans. In conclusion, we discovered here that mutations in 4 genes encoding components of the outer ring subunits of the NPC cause SRNS and thereby provide further evidence that specific hypomorphic mutations in these essential genes cause a distinct, organ-specific phenotype