Simulation evaluation of TIMER, a time-based, terminal air traffic, flow-management concept

A description of a time-based, extended terminal area ATC concept called Traffic Intelligence for the Management of Efficient Runway scheduling (TIMER) and the results of a fast-time evaluation are presented. The TIMER concept is intended to bridge the gap between today's ATC system and a future automated time-based ATC system. The TIMER concept integrates en route metering, fuel-efficient cruise and profile descents, terminal time-based sequencing and spacing together with computer-generated controller aids, to improve delivery precision for fuller use of runway capacity. Simulation results identify and show the effects and interactions of such key variables as horizon of control location, delivery time error at both the metering fix and runway threshold, aircraft separation requirements, delay discounting, wind, aircraft heading and speed errors, and knowledge of final approach speed

SAGE 1 data user's guide

A guide for using the data products from the Stratospheric Aerosol and Gas Experiment 1 (SAGE 1) for scientific investigations of stratospheric chemistry related to aerosol, ozone, nitrogen dioxide, dynamics, and climate change is presented. A detailed description of the aerosol profile tape, the ozone profile tape, and the nitrogen dioxide profile tape is included. These tapes are the SAGE 1 data products containing aerosol extinction data and ozone and nitrogen dioxide concentration data for use in the different scientific investigations. Brief descriptions of the instrument operation, data collection, processing, and validation, and some of the scientific analyses that were conducted are also included

Cosmological Acceleration Through Transition to Constant Scalar Curvature

As shown by Parker and Raval, quantum field theory in curved spacetime gives a possible mechanism for explaining the observed recent acceleration of the universe. This mechanism, which differs in its dynamics from quintessence models, causes the universe to make a transition to an accelerating expansion in which the scalar curvature, R, of spacetime remains constant. This transition occurs despite the fact that we set the renormalized cosmological constant to zero. We show that this model agrees very well with the current observed type-Ia supernova (SNe-Ia) data. There are no free parameters in this fit, as the relevant observables are determined independently by means of the current cosmic microwave background radiation (CMBR) data. We also give the predicted curves for number count tests and for the ratio, w(z), of the dark energy pressure to its density, as well as for dw(z)/dz versus w(z). These curves differ significantly from those obtained from a cosmological constant, and will be tested by planned future observations.Comment: 31 pages, 7 figures; to appear in ApJ. Corrected numerical results; described quantum basis of theory; 18 references added; 2 figures adde

Delivery performance of conventional aircraft by terminal-area, time-based air traffic control: A real-time simulation evaluation

A description and results are presented of a study to measure the performance and reaction of airline flight crews, in a full workload DC-9 cockpit, flying in a real-time simulation of an air traffic control (ATC) concept called Traffic Intelligence for the Management of Efficient Runway-scheduling (TIMER). Experimental objectives were to verify earlier fast-time TIMER time-delivery precision results and obtain data for the validation or refinement of existing computer models of pilot/airborne performance. Experimental data indicated a runway threshold, interarrival-time-error standard deviation in the range of 10.4 to 14.1 seconds. Other real-time system performance parameters measured include approach speeds, response time to controller turn instructions, bank angles employed, and ATC controller message delivery-time errors

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Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73154/1/j.1753-4887.1990.tb02944.x.pd

Doctors at Risk: A Problem As Viewed by Decision Analysis

The authors closely analyze a case in which a Peer Review Organization cited a physician for treatment with potential for significant adverse effect. They also critique the regulatory scheme under which peer review occurs and conclude that such regulation interferes with physicians\u27 primary obligations, fails to encourage cost-effective behavior and may decrease the quality of medical care

Boas's Changes in Bodily Form: The Immigrant Study, Cranial Plasticity, and Boas's Physical Anthropology

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65980/1/aa.2003.105.2.326.pd

Hunting Success and Northern Bobwhite Density on Tall Timbers Research Station: 1970-2001

Hunting success, defined as number of coveys found/hr of hunting, has been used as an index of population size of northern bobwhites (Colinus virginianus). However, the relationship between hunting success and bobwhite density has not been documented on individual study areas. We related estimates of bobwhite density on a 445-ha section of Tall Timbers Research Station (TTRS) to the number of coveys flushed/hr of hunting, 1970–2001. To estimate density of bobwhites, we captured bobwhites in baited-funnel traps for a 2–3 week period and recaptured 15–20% of banded birds by systematically hunting the study area using pointing bird dogs. Bobwhite population sizes, calculated using a bias-corrected Peterson estimate, were converted to densities because of changes in study area size over time. Annual density estimates and hunting success ranged from 0.7–4.8 bobwhites/ha and 0.5–2.9 covey finds/hr over the study period, respectively. We assessed the variance in bobwhite abundance explained by year and hunting success using multiple linear regression. There was a significant positive relationship between covey finds/hr and bobwhite density (t25 = 9.070, P = \u3c0.0001). Covey finds/hr explained the greatest amount of variation (r2 = 0.77) in density. Our data suggest that if hunting procedures are standardized over time, hunting success may be used to index bobwhite abundance, and potentially provide crude estimates of population density