16,158 research outputs found

    Digital interface for bi-directional communication between a computer and a peripheral device

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    For transmission of data from the computer to the peripheral, the computer initially clears a flipflop which provides a select signal to a multiplexer. A data available signal or data strobe signal is produced while tht data is being provided to the interface. Setting of the flipflop causes a gate to provide to the peripherial a signal indicating that the interface has data available for transmission. The peripheral provides an acknowledge or strobe signal to transfer the data to the peripheral. For transmission of data from the peripheral to the computer, the computer presents the initially cleared flipflop. A data request signal from the peripheral indicates that the peripheral has data available for transmission to the computer. An acknowledge signal indicates that the interface is ready to receive data from the peripheral and to strobe that data into the interface

    The design of low cost structures for extensive ground arrays

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    The development of conceptual designs of solar array support structures and their foundations including considerations of the use of concrete, steel, aluminum, or timber are reported. Some cost trends were examined by varying selected parameters to determine optimum configurations. Detailed civil/structural design criteria were developed. Using these criteria, eight detailed designs for support structures and foundations were developed and cost estimates were made. As a result of the study wind was identified as the major loading experienced by these low height structures, whose arrays are likely to extend over large tracts of land. Proper wind load estimating is considered essential to developing realistic structural designs and achieving minimum cost support structures. Wind tunnel testing of a conceptual array field was undertaken and some of the resulting wind design criteria are presented. The SPS rectenna system designs may be less sensitive to wind load estimates, but consistent design criteria remain important

    Comment on Octet Baryon Magnetic Moments in the Chiral Quark Model with Configuration Mixing

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    The importance of exchange currents, and of conserving isotopic spin at both the quark and baryon levels in application of the chiral quark model to any calculation of baryon magnetic moments is emphasized.Comment: 5 pages, Latex fil

    Guided Tissue Remineralization of Resin-Bonded Acid-Etched Dentin

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    Contemporary biomineralization strategies incorporate non-classical crystallization pathways of fluidic amorphous nanoprecursors and mesoscopic transformation. Using two functional biomimetic molecules, we previously regenerated mineralized dentin from acid-etched dentin using the Guided Tissue Remineralization (GTR) approach, with definitive intrafibrillar remineralization of type-I collagen. Degradation of denuded collagen within dentin adhesive resin-infiltrated dentin is a pertinent problem in dentin bonding. Here, we show that GTR provides a means of salvaging these degrading bonds by remineralizing resin-dentin interfaces. The GTR medium consists of a Portland cement/simulated body fluid that includes polyacrylic acid and polyvinylphosphonic acid biomimetic analogs for amorphous calcium phosphate dimension regulation and collagen targeting. Both interfibrillar and intrafibrillar apatites became readily discernible within the adhesive-bonded dentin after 2-4 months. Amorphous nanoprecursors created by GTR also penetrated the adhesive resin matrix to create nanocomposites. We anticipate GTR to be the starting point for more sophisticated strategies in extending the longevity of resin-dentin bonds

    Faster Calculation of Superquadric Shapes

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    Nonparametric methods of calculating points on the curve produce the recently introduced superquadric objects at great savings in time

    Estimating Sighting Proportions of American Alligator Nests during Helicopter Survey

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    Proportions of American alligator (Alligator mississippiensis) nests sighted during aerial survey in Florida were estimated based upon multiple surveys by different observers. We compared sighting proportions across habitats, nesting seasons, and observer experience levels. The mean sighting proportion across all habitats and years was 0.736 (SE=0.024). Survey counts corrected by the mean sighting proportion reliably predicted total nest counts (R2=0.933). Sighting proportions did not differ by habitat type (P=0.668) or year P=0.328). Experienced observers detected a greater proportion of nests (P<O.OOOl) than did either less experienced or inexperienced observers. Reliable estimates of nest abundance can be derived from aerial counts of alligator nests when corrected by the appropriate sighting proportion

    Flight evaluation of the STOL flare and landing during night operations

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    Simulated instrument approaches were made to Category 1 minimums followed by a visual landing on a 100 x 1700 ft STOL runway. Data were obtained for variations in the aircraft's flare response characteristics and control techniques and for different combinations of aircraft and runway lighting and a visual approach slope indication. With the complete aircraft and runway lighting and visual guidance no degradation in flying qualities or landing performance was observed compared to daylight operations. elimination of the touchdown zone floodlights or the aircraft landing lights led to somewhat greater pilot workload; however, the landing could still be accomplished successfully. Loss of both touchdown zone and aircraft landing lights led to a high workload situation and only a marginally adequate to inadequate landing capability

    A paediatric telecardiology service for district hospitals in south-east England: an observational study.

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    The attached article is a Publisher version of the final published version which may be accessed at the link below. Copyright © 2010 BMJ Publishing Group Ltd & Royal College of Paediatrics and Child Health. All rights reservedOBJECTIVES: To compare caseloads of new patients assessed by paediatric cardiologists face-to-face or during teleconferences, and assess NHS costs for the alternative referral arrangements. DESIGN: Prospective cohort study over 15 months. SETTING: Four district hospitals in south-east England and a London paediatric cardiology centre. PATIENTS: Babies and children. INTERVENTION: A telecardiology service introduced alongside outreach clinics. MEASUREMENTS: Clinical outcomes and mean NHS costs per patient. RESULTS: 266 new patients were studied: 75 had teleconsultations (19 of 42 newborns and 56 of 224 infants and children). Teleconsultation patients generally were younger (49% being under 1 year compared with 32% seen personally (p = 0.025)) and their symptoms were not as severe. A cardiac intervention was undertaken immediately or planned for five telemedicine patients (7%) and 30 conventional patients (16%). However, similar proportions of patients were discharged after being assessed (32% telemedicine and 39% conventional). During scheduled teleconferences the mean duration of time per patient in sessions involving real-time echocardiography was 14.4 min, and 8.5 min in sessions where pre-recorded videos were transmitted. Mean cost comparisons for telemedicine and face-to-face patients over 14-day and 6-month follow-up showed the telecardiology service to be cost-neutral for the three hospitals with infrequently-held outreach clinics (1519 UK pounds vs 1724 UK pounds respectively after 14 days). CONCLUSION: Paediatric cardiology centres with small cadres of specialists are under pressure to cope with ever-expanding caseloads of new patients with suspected anomalies. Innovative use of telecardiology alongside conventional outreach services should suitably, and economically, enhance access to these specialists.The Department of Health and the Charitable Funds Committee of the Royal Brompton and Harefield NHS Trust funded the project

    Survival and Growth of American Alligator (Alligator mississippiensis) hatchlings after artificial incubation and repatriation

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    Hatchling American Alligators (Alligator mississippiensis) produced from artificially incubated wild eggs were returned to their natal areas (repatriated). We compared artificially incubated and repatriated hatchlings released within and outside the maternal alligator’s home range with naturally incubated hatchlings captured and released within the maternal alligator’s home range on Lake Apopka, Lake Griffin, and Orange Lake in Florida. We used probability of recapture and total length at approximately nine months after hatching as indices of survival and growth rates. Artificially incubated hatchlings released outside of the maternal alligator’s home range had lower recapture probabilities than either naturally incubated hatchlings or artificially incubated hatchlings released near the original nest site. Recapture probabilities of other treatments did not differ significantly. Artificially incubated hatchlings were approximately 6% shorter than naturally incubated hatchlings at approximately nine months after hatching. We concluded that repatriation of hatchlings probably would not have long-term effects on populations because of the resiliency of alligator populations to alterations of early age-class survival and growth rates of the magnitude that we observed. Repatriation of hatchlings may be an economical alternative to repatriation of older juveniles for population restoration. However, the location of release may affect subsequent survival and growth
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