4,473 research outputs found
Performance improvements of an F-15 airplane with an integrated engine-flight control system
An integrated flight and propulsion control system has been developed and flight demonstrated on the NASA Ames-Dryden F-15 research aircraft. The highly integrated digital control (HIDEC) system provides additional engine thrust by increasing engine pressure ratio (EPR) at intermediate and afterburning power. The amount of EPR uptrim is modulated based on airplane maneuver requirements, flight conditions, and engine information. Engine thrust was increased as much as 10.5 percent at subsonic flight conditions by uptrimming EPR. The additional thrust significantly improved aircraft performance. Rate of climb was increased 14 percent at 40,000 ft and the time to climb from 10,000 to 40,000 ft was reduced 13 percent. A 14 and 24 percent increase in acceleration was obtained at intermediate and maximum power, respectively. The HIDEC logic performed fault free. No engine anomalies were encountered for EPR increases up to 12 percent and for angles of attack and sideslip of 32 and 11 degrees, respectively
Political Oversight, the Rule of Law, and Iran-Contra
What I would like to talk about today, and I will use Iran-Contra as an illustration for much of it, is what I believe to be the conflict between two protective systems: (1) the rule of law as it is enforced by courts and lawyers; and (2) political oversight as set up by our Constitution and as it is carried out by political forces in Congress, particularly in it\u27s oversight of the President. It is my conclusion that in some ways they are like having two alarm systems on your house: A silent system that communicates with police headquarters if there is a burglar on the premises and second alarm which blows a noisy whistle that scares the burglar off
A survey of teacher feeling in selected areas concerned with evaluation of teacher service to children
Thesis (Ed.M.)--Boston Universit
Power utilization of Meramec Spring
Meramec Spring is situated in the east central part of Phelps County, Missouri, about one quarter of a mile west of the county line. The spring proper is in the center of a small natural amphitheatre from which the water flows through a valley which has a bearing of approximately N. 30 degrees W., about one quarter of a mile from the spring the course of the stream is changed about sixty degrees to the east, one quarter mile from this bend the stream joins the Meramec River...The volume of water delivered by the spring is modified to some extent by the amount of rain precipitated in the surrounding district...The improvements contemplated are a dam and sluice to impound and deliver the water from the spring to the turbine in the power house --pages 1 -2
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PreView: a Randomized Trial of a Multi-site Intervention in Diverse Primary Care to Increase Rates of Age-Appropriate Cancer Screening.
BackgroundWomen aged 50-70 should receive breast, cervical (until age 65), and colorectal cancer (CRC) screening; men aged 50-70 should receive CRC screening and should discuss prostate cancer screening (PSA). PreView, an interactive, individually tailored Video Doctor Plus Provider Alert Intervention, adresses all cancers for which average risk 50-70-year-old individuals are due for screening or screening discussion.MethodsWe conducted a randomized controlled trial in 6 clinical sites. Participants were randomized to PreView or a video about healthy lifestyle. Intervention group participants completed PreView before their appointment and their clinicians received a "Provider Alert." Primary outcomes were receipt of mammography, Pap tests (with or without HPV testing), CRC screening (FIT in last year or colonoscopy in last 10 years), and PSA screening discussion. Additional outcomes included breast, cervical, and CRC screening discussion.ResultsA total of 508 individuals participated, 257 in the control group and 251 in the intervention group. Screening rates were relatively high at baseline. Compared with baseline screening rates, there was no significant increase in mammography or Pap smear screening, and a nonsignificant increase (18% vs 12%) in CRC screening. Intervention participants reported a higher rate of PSA discussion than did control participants (58% vs 36%: P < 0.01). Similar increases were seen in discussions about mammography, cervical cancer, and CRC screening.ConclusionIn clinics with relatively high overall screening rates at baseline, PreView did not result in significant increases in breast, cervical, or CRC screening. PreView led to an increase in PSA screening discussion. Clinician-patient discussion of all cancer screenings significantly increased, suggesting that interventions like PreView may be most useful when discussion of the pros and cons of screening is recommended and/or with patients reluctant to undergo screening. Future research should investigate PreView's impact on those who are hesitant or reluctant to undergo screening.Trial registrationClinicalTrials.gov: NCT02264782
Dynamic analysis of a magnetic bearing system with flux control
Using measured values of two-dimensional forces in a magnetic actuator, equations of motion for an active magnetic bearing are presented. The presence of geometric coupling between coordinate directions causes the equations of motion to be nonlinear. Two methods are used to examine the unbalance response of the system: simulation by direct integration in time; and determination of approximate steady state solutions by harmonic balance. For relatively large values of the derivative control coefficient, the system behaves in an essentially linear manner, but for lower values of this parameter, or for higher values of the coupling coefficient, the response shows a split of amplitudes in the two principal directions. This bifurcation is sensitive to initial conditions. The harmonic balance solution shows that the separation of amplitudes actually corresponds to a change in stability of multiple coexisting solutions
Collaborative Inquiry: Expanding the Boundaries of Knowledge Construction in Graduate Adult Education Research
The purpose of this roundtable session is to share ideas about collaborative inquiry as a research methodology. Facilitators include a faculty member from a doctoral program that encourages collaborative learning and collaborative inquiry, and two students, from the same doctoral program, who completed a fully collaborative doctoral research project
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