5,513 research outputs found
Performance analysis of flexible aircraft with active control
Small perturbation equations of motion of a flexible aircraft with an active control technology (ACT) system were developed to evaluate the stability and performance of the controlled aircraft. The total aircraft system was formulated in state vector format and the system of equations was completed with fully unsteady and low frequency aerodynamics for arbitrary, complex configurations based on a potential aerodynamic method. The ACT system equations were incorporated in the digital computer program FCAP (Flight Control Analysis Program) which can be used for the analysis of complete aircraft configurations, including control system, with either low frequency or fully unsteady aerodynamics. The application of classical performance analyses including frequency response, poles and zeros, mean square response, and time response in FCAP in state vector format was discussed
Rotational properties of the binary and non-binary populations in the Trans-Neptunian belt
We present results for the short-term variability of Binary Trans-Neptunian
Objects (BTNOs). We performed CCD photometric observations using the 3.58 m
Telescopio Nazionale Galileo, the 1.5 m Sierra Nevada Observatory telescope,
and the 1.23 m Centro Astronomico Hispano Aleman telescope at Calar Alto
Observatory. We present results based on five years of observations and report
the short-term variability of six BTNOs. Our sample contains three classical
objects: 2003MW12, or Varda, 2004SB60, or Salacia, and 2002 VT130; one detached
disk object: 2007UK126; and two resonant objects: 2007TY430 and 2000EB173, or
Huya. For each target, possible rotational periods and/or photometric
amplitudes are reported. We also derived some physical properties from their
lightcurves, such as density, primary and secondary sizes, and albedo. We
compiled and analyzed a vast lightcurve database for Trans-Neptunian Objects
(TNOs) including centaurs to determine the lightcurve amplitude and spin
frequency distributions for the binary and non-binary populations. The mean
rotational periods, from the Maxwellian fits to the frequency distributions,
are 8.63+/-0.52 h for the entire sample, 8.37+/-0.58 h for the sample without
the binary population, and 10.11+/-1.19 h for the binary population alone.
Because the centaurs are collisionally more evolved, their rotational periods
might not be so primordial. We computed a mean rotational period, from the
Maxwellian fit, of 8.86+/-0.58 h for the sample without the centaur population,
and of 8.64+/-0.67 h considering a sample without the binary and the centaur
populations. According to this analysis, regular TNOs spin faster than
binaries, which is compatible with the tidal interaction of the binaries.
Finally, we examined possible formation models for several systems studied in
this work and by our team in previous papers.Comment: Accepted for publication in Astronomy and Astrophysics (June 26th,
2014); minor changes with published version; 21 pages, 17 figures, 7 table
Activities for social skills development in deaf children preparing to enter the mainstream
A sample of regular education teachers was surveyed to assess the social skills of recently mainstreamed students from oral deaf programs in their classrooms. In addition, a curriculum of social skills activities was developed to help prepare students from oral deaf schools to enter the mainstream
Rethinking Anti-Aggregation Doctrine
The article focuses on a new strategy to anti-aggregation agreements, contractual provisions which prohibit parties to participate in class action. It discusses the U.S. Supreme Court\u27s decision in AT&T Mobility LLC v. Concepcion, suggesting that such agreements should be based on actual regulatory compliance. It mentions that anti-aggregation agreements are applied by default, but in case there will be an irreversible harm occurring to party, such agreements will not be applicable
Administrative Sabotage
Government can sabotage itself. From the president’s choice of agency heads to agency budgets, regulations, and litigating positions, presidents and their appointees have undermined the very programs they administer. But why would an agency try to put itself out of business? And how can agencies that are subject to an array of political and legal checks sabotage statutory programs?
This Article offers an account of the “what, why, and how” of administrative sabotage that answers those questions. It contends that sabotage reflects a distinct mode of agency action that is more permanent, more destructive, and more democratically illegitimate than more-studied forms of maladministration. In contrast to an agency that shirks its statutory duties or drifts away from Congress’s policy goals, one engaged in sabotage aims deliberately to kill or nullify a program it administers. Agencies sabotage because presidents ask them to. Facing pressure to dismantle statutory programs in an environment where securing legislation from Congress is difficult and politically costly, presidents pursue retrenchment through the administrative state.
Building on this positive theory of administrative sabotage, this Article considers legal responses. The best response, this Article contends, is not reforms to the cross-cutting body of administrative law that structures most agency action. Rather, the risk of sabotage is better managed through changes to how statutory programs are designed. Congress’s choices about agency leadership, the concentration or dispersal of authority to implement statutory programs, the breadth of statutory delegations, and other matters influence the likelihood that sabotage will succeed or fail. When lawmakers create or modify federal programs, they should design them to be less vulnerable to sabotage by the very agencies that administer them
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