1,425 research outputs found

    NASA/Ames Research Center DC-8 data system

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    In-flight facility data acquisition, distribution, and recording on the NASA Ames Research Center (ARC) DC-8 are performed by the Data Acquisition and Distribution System (DADS). Navigational and environmental data collected by the DADS are converted to engineering units and distributed real-time to investigator stations once per second. Selected engineering units data are printed and displayed on closed circuit television monitors throughout flights. An in-flight graphical display of the DC-8 flight track (with barbs indicating wind direction and magnitude) has recently been added to the DADS capabilities. Logging of data run starts/stops and commentary from the mission director are also provided. All data are recorded to hard disk in-flight and archived to tape medium post-flight. Post-flight, hard copies of the track map and mission director's log are created by the DADS. The DADS is a distributed system consisting of a data subsystem, an Avionic Serial Data-to-VMEbus (ASD2VME) subsystem, and a host subsystem. Each subsystem has a dedicated central processing unit (CPU) and is capable of stand-alone operation. All three subsystems are housed in a single 20-slot VME chassis and communicate with each other over the VMEbus. The data and host subsystems are briefly discussed, and the DC-8 DADS internal configuration and system block diagram are presented

    LibCPIXE: a PIXE simulation open-source library for multilayered samples

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    Most particle induced X-ray emission (PIXE) data analysis codes are not focused on handling multilayered samples. We have developed an open-source library called "LibCPIXE", for PIXE data analysis. It is written in standard C and implements functions for simulating X-ray yields of PIXE spectra taken from arbitrary samples, including multilayered targets. The library is designed to be fast, portable, modular and scalable, as well as to facilitate its incorporation into any existing program. In order to demonstrate the capabilities of the library, a program called CPIXE was developed and used to analyze various real samples involving both bulk and layered samples. Just as the library, the CPIXE source code is freely available under the General Public License. We demonstrate that it runs both under GNU/Linux systems as well as under MS Windows. There is in principle no limitation to port it to other platforms

    1910-01-05, Letter from C.I. Scofield to A.C. Dixon acceptance on writing an article

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    PDF is a transcript onlyhttps://digitalcommons.biola.edu/the-fundamentals-correspondence/1005/thumbnail.jp

    Soft-tissue specimens from pre-European extinct birds of New Zealand

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    We provide the first complete review of soft tissue remains from New Zealand birds that became extinct prior to European settlement (c. AD 1800). These rare specimens allow insights into the anatomy and appearance of the birds that are not attainable from bones. Our review includes previously unpublished records of ‘lost’ specimens, and descriptions of recently discovered specimens such as the first evidence of soft tissues from the South Island goose (Cnemiornis calcitrans). Overall, the soft tissue remains are dominated by moa (with specimens from each of the six genera), but also include specimens from Finsch's duck (Chenonetta finschi) and the New Zealand owlet-nightjar (Aegotheles novaezealandiae). All desiccated soft tissue specimens that have radiocarbon or stratigraphic dates are late Holocene in age, and most have been found in the semi-arid region of Central Otago

    Bottom-up Photonic Crystal Lasers

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    The directed growth of III–V nanopillars is used to demonstrate bottom-up photonic crystal lasers. Simultaneous formation of both the photonic band gap and active gain region is achieved via catalyst-free selective-area metal–organic chemical vapor deposition on masked GaAs substrates. The nanopillars implement a GaAs/InGaAs/GaAs axial double heterostructure for accurate, arbitrary placement of gain within the cavity and lateral InGaP shells to reduce surface recombination. The lasers operate single-mode at room temperature with low threshold peak power density of ~625 W/cm^2. Cavity resonance and lasing wavelength is lithographically defined by controlling pillar pitch and diameter to vary from 960 to 989 nm. We envision this bottom-up approach to pillar-based devices as a new platform for photonic systems integration

    Letter from Lydia Ely [et al.] to John Muir, 1897 Dec 10.

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    Milwaukee, Dec. & [10?], 1897.Mr, John Muir,Bear Sir:-Upon the inclosed water-marked and engraved slip you are requested to write your autograph and profession, and return the same in the accompanying envelope. This autograph will be one among about one thousand names of persons eminent in the National, State and Municipal government of this country, and of men and women of foremost rank in the professions, in affairs, and in the fine arts; these, bound together in one grand volume, will be sold for the benefit of the Soldiers\u27 Monument of Milwaukee.A bronze group, already accepted, is now being executed in Rome by Sculptor John Saverino Conway. Twenty thousand dollars (20,000)hasalreadybeenraised,andtomeetthedeficiency(about20,000) has already been raised, and to meet the deficiency (about 10,000), this volume of autographs to which we are asking you to contribute will be sold.Thus far over five hundred names of statesmen, diplomates and high officials have been given; more than one hundred of the most distinguished musicians and dramatists have kindly responded, and unsolicited have added musical notations, sentiments or quotations, thus contributing to make the volume unique and priceless. The Scientific division is just reached, and you are invited to be on this honorable roll. A remark in pen or pencil, or the name of your work which is most distinguishing, or best known, or anything you are willing to add, will be greatly appreciated and materially aid in the sale of the book.Please give your autograph and profession if you do not add anything thereto. The book will be distinguished and every name conspicuous in its department. It will be offered to the world for sale; already proposals for its purchase are made.Thanking you in advance.Very respectfully,(Signed) LYDIA ELY.(Signed) E. SCOFIELD,Governor of Wisconsin.(Signed) W. Q. RAUSCHENBERGER,Mayor of Milwaukee.0237

    Ascidians of South Padre Island, Texas, with a Key to Species

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    The ascidians of South Padre Island, Texas were surveyed in August 2004. Because the subtidal area is limited to soft sediments, the survey was restricted to marina floats and pilings, harbor buoys, boat hulls and other artificial substrates which offer suitable attachment surfaces for ascidians. Fifteen species were documented, with multiple species representing each of the three orders of ascidians. None of the species found in this survey are native, suggesting they were all introduced through boat traffic. About half the species were found in a reproductive state, however, indicating that they have established local breeding populations

    Brood patch and sex-ratio observations indicate breeding provenance and timing in New Zealand storm petrel (Fregetta maoriana)

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    We used measurements of brood patch and moult status to estimate the breeding phenology of New Zealand Storm-Petrel, using birds caught at sea within the Hauraki Gulf Marine Park near Auckland, New Zealand. Birds caught October–January had completely downy brood patches, whereas birds caught February–April had bare brood patches with an observed male bias in the February sex-ratio, consistent with a female pre-laying exodus typical of petrels and with the existence of an unknown colony in the region. No birds captured exhibited primary moult, which is known to occur in storm-petrels during their non-breeding season. Our data support the conclusion that the New Zealand storm-petrel breeds during January–June in northern New Zealand and that field surveys for the species on offshore islands in this region during this period are warrante

    Repair of Failing Spirit Lake Outlet Tunnel at Mount St. Helens

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    The 18 May 1980 eruption of Mount St. Helens resulted in one of the largest debris avalanches recorded in history. The debris avalanche blocked the natural outlet of Spirit Lake. To prevent an uncontrolled and catastrophic lake break-out, the U.S. Army Corps of Engineers (USACE) constructed the Spirit Lake Outlet Tunnel from 1984 to 1985. Because Spirit Lake is located in the Mount St. Helens National Volcanic Monument, the project was transferred to the U.S. Forest Service (USFS) for ownership and management. During original tunnel construction, the most difficulty occurred within the 90-m-wide Julie and Kathy L. shear zone complex. In 1996, tunnel walls within this complex experienced significant convergence, which required major repair along a 30 m segment. During inspections in 2014 and 2015, a 10 m segment at the upstream end of the complex, which had experienced slow heave in the past, was observed to have experienced an increase in heave of approximately 0.6 m, which decreased the hydraulic capacity of the tunnel below acceptable limits. The USACE, in accordance with and with funding from the USFS, designed a repair based on the rib set-shotcrete support system that was used for the 1996 repair. In addition to removing and arresting the heave, the 2015 repair was sized to be compatible with a future potential rehabilitation involving stabilizing and re-grading the invert profile of the Julie and Kathy L. shear zone complex. The 2015 repair construction contract was awarded in September 2015 for $3 million
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