How Modern Day Networks Are Enabling a Digital Advantage - Not a Digital Divide Companies and solution providers are realizing that the flawed architecture of single enterprise-centric solutions ...cannot be patched up to support today’s highly dynamic and interconnected business environment. Just as cloud-based social networks have created new approaches to how we manage our personal and business relationships, new network platforms and the resulting communities are changing how business is conducted between the end consumer and all the companies on the network. Tips to Starting Your Own Digital Transformation Journey Historically, and like traditional ERP systems, any enterprise system implementation often required a big bang approach to deploy. Networks are also deploying integrating AI pattern recognition and machine learning to create Systems of Intelligence that add new levels of intelligent analytics on top of Systems of Engagement to enable disruptive business models. Once your supply chain partners are connected to the network, each party can easily publish updates such as schedules, capacity, statuses, etc., and all parties will receive the info by simply subscribing to receiving the necessary information. Greg BradyCEO and Founder of One Network Enterprises Aligning all parties to consumer behavior and predicted trends no matter how far removed a company is from the end customer drives higher quality growth and fiscal health.
Future large segmented space telescopes and their coronagraphic instruments are expected to provide the resolution and sensitivity to observe Earth-like planets with a 10^10 contrast ratio at less ...than 100 mas from their host star. Advanced coronagraphs and wavefront control methods will enable the generation of high-contrast dark holes in the image of an observed star. However, drifts in the optical path of the system will lead to pointing errors and other critical low-order aberrations that will prevent maintenance of this contrast. To measure and correct for these errors, we explore the use of a Zernike wavefront sensor (ZWFS) in the starlight rejected and filtered by the focal plane mask of a Lyot-type coronagraph. In our previous work, the analytical phase reconstruction formalism of the ZWFS was adapted for a filtered beam. We now explore strategies to actively compensate for these drifts in a segmented pupil setup on the High-contrast imager for Complex Aperture Telescopes (HiCAT). This contribution presents laboratory results from closed-loop compensation of bench internal turbulence as well as known introduced aberrations using phase conjugation and interaction matrix approaches. We also study the contrast recovery in the image plane dark hole when using a closed loop based on the ZWFS.
Imaging exo-Earths is an exciting but challenging task because of the 10^-10 contrast ratio between these planets and their host star at separations narrower than 100 mas. Large segmented aperture ...space telescopes enable the sensitivity needed to observe a large number of planets. Combined with coronagraphs with wavefront control, they present a promising avenue to generate a high-contrast region in the image of an observed star. Another key aspect is the required stability in telescope pointing, focusing, and co-phasing of the segments of the telescope primary mirror for long-exposure observations of rocky planets for several hours to a few days. These wavefront errors should be stable down to a few tens of picometers RMS, requiring a permanent active correction of these errors during the observing sequence. To calibrate these pointing errors and other critical low-order aberrations, we propose a wavefront sensing path based on Zernike phase-contrast methods to analyze the starlight that is filtered out by the coronagraph at the telescope focus. In this work we present the analytical retrieval of the incoming low order aberrations in the starlight beam that is filtered out by an Apodized Pupil Lyot Coronagraph, one of the leading coronagraph types for starlight suppression. We implement this approach numerically for the active control of these aberrations and present an application with our first experimental results on the High-contrast imager for Complex Aperture Telescopes (HiCAT) testbed, the STScI testbed for Earth-twin observations with future large space observatories, such as LUVOIR and HabEx, two NASA flagship mission concepts.
Proc. SPIE 10698, Space Telescopes and Instrumentation 2018:
Optical, Infrared, and Millimeter Wave, 106983N (2018) The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a
...hardware simulator for wavefront sensing and control designed to produce
JWST-like images. A model of the JWST three mirror anas- tigmat is realized
with three lenses in the form of a Cooke triplet, which provides JWST-like
optical quality over a field equivalent to a NIRCam module. An Iris AO
hexagonally segmented mirror stands in for the JWST primary. This setup
successfully produces images extremely similar to expected JWST in-flight point
spread functions (PSFs), and NIRCam images from cryotesting, in terms of the
PSF morphology and sampling relative to the diffraction limit. The segmentation
of the primary mirror into subapertures introduces complexity into wavefront
sensing and control (WFS&C) of large space based telescopes like JWST. JOST
provides a platform for independent analysis of WFS&C scenarios for both
commissioning and maintenance activities on such ob- servatories. We present an
update of the current status of the testbed including both single field and
wide-field alignment results. We assess the optical quality of JOST over a wide
field of view to inform the future imple- mentation of different wavefront
sensing algorithms including the currently implemented Linearized Algorithm for
Phase Diversity (LAPD). JOST complements other work at the Makidon Laboratory
at the Space Telescope Science Institute, including the High-contrast imager
for Complex Aperture Telescopes (HiCAT) testbed, that investigates coronagraphy
for segmented aperture telescopes. Beyond JWST we intend to use JOST for WFS&C
studies for future large segmented space telescopes such as LUVOIR.
Frontalis-associated sarcoma of the forehead Randall, D A; Brady, J G; Boone, J L ...
Journal of the American Academy of Dermatology,
12/1994, Letnik:
31, Številka:
6
Journal Article
Myiasis, the infestation of humans or other vertebrates with fly larvae, may appear as furuncular nodules. Furuncular myiasis occurring in the Western hemisphere, especially in Central and South ...America, is usually caused by Dermatobia hominis infestation. Travel history, gross examination, and histologic evaluation of the submitted fly larvae will allow the clinician and dermatopathologist to identify the causative organism. We report two cases of furuncular myiasis due to Dermatobia hominis and review the clinical and histopathologic findings pertinent to its diagnosis. In addition, we attempted to identify some of the cardinal internal structures of this organism by extrapolating known information about insect internal anatomy and physiology to the structures visualized during serial transverse sectioning of the larvae.
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