5,787 research outputs found
Tradeoff analysis of technology needs for public service helicopters
The design requirements for a family or type of Public Service Helicopter (PSH) is examined which will satisfy the needs of municipal and state governments in the following mission areas: Emergency Medical Service--Airborne Rescue Squad; Law Enforcement; Search and Rescue; and Environmental Control (Fire Fighting, Pollution, Resource Management). The report compares both design and performance requirements as specified by the PSH user's group against current technological capabilities, RTOPS and US Army LHX design requirements. The study explores various design trade-offs and options available to the aircraft designer/manufacturer in order to meet the several criteria specified by the PSH user's group. In addition, the report includes a brief assessment of the feasibility of employing certain advanced rotorcraft designs to meet the stringent combination of operational capabilities desired by the Public Service Helicopter Users
An algorithm for determining program feasibility of a multi-mode PAM commutator telemetry system Technical report no. 10
Algorithm formulation for evaluation of strapping arrangement programs for PAM multimode commutation system of Saturn telemetry syste
Statistical quality control applied to a telemetry system acceptance prodedure Technical report no. 13
Statistical quality control applied to telemetry system acceptance procedur
A statistical investigation of the effects contributed by tape recorders and by wow and flutter of magnetic tape on the accuracy of a telemetry system Technical report no. 15
Effects contributed by tape recorders and by wow and flutter of magnetic tape on accuracy of telemetry syste
Analysis of the linearity characteristics, tape recorders and compensation effects in the FM/FM telemetry system
Linearity characteristics, tape recorder effects, and tape speed compensation effects in FM/FM TELEMETRY syste
Modifiable factors associated with depression and anxiety in multiple sclerosis
Objectives: Modifiable lifestyle factors are implicated in multiple sclerosis (MS) symptoms but their role in mood is unclear. This study aimed to investigate associations between lifestyle and depression and anxiety in Australian participants with MS.Materials and Methods: Self-reported data from the Australian Multiple Sclerosis Longitudinal Study included the Hospital Anxiety and Depression Scale (HADS) and lifestyle measurements from 1500 participants. SNAP score (range 0-5) was the sum of non-smoking, sufficient fruit/vegetable intake, non-hazardous alcohol consumption, sufficient physical activity and healthy BMI. Analyses by log-binomial and linear regression were adjusted for confounding.Results: Symptoms of depression and anxiety were prevalent in 27% and 40%, respectively; 20% had both. Mean SNAP score was 2.7/5; only 3% met all healthy lifestyle recommendations. Only 10% reported adequate fruit/vegetable intake, and 22% reported a combination of unhealthy BMI, inadequate physical activity and inadequate nutrition. A healthier SNAP score was associated with lower depression prevalence (adjusted prevalence ratio 0.83 [95% CI 0.75, 0.92] per unit increase) and depression severity (adjusted β-0.44 [95% CI -0.64, -0.24]), but not with anxiety.Conclusions: Modifiable lifestyle factors are associated with lower frequency and severity of depression, but not anxiety, in Australian people with multiple sclerosis. The associations between a healthier SNAP score and lower depression are likely bi-directional. SNAP risk factor prevalence and co-occurrence, especially inadequate nutrition and low physical activity, were high among Australians with MS
The Electron Scattering Region in Seyfert Nuclei
The electron scattering region (ESR) is one of important ingredients in
Seyfert nuclei because it makes possible to observe the hidden broad line
region (hereafter HBLR) in some type 2 Seyfert nuclei (hereafter S2s). However,
little is known about its physical and geometrical properties. Using the number
ratio of S2s with and without HBLR, we investigate statistically where the ESR
is in Seyfert nuclei. Our analysis suggests that the ESR is located at radius
between 0.01 pc and 0.1 pc from the central engine. We also
discuss a possible origin of the ESR briefly.Comment: 5 pages and 1 figure. The Astrophysical Journal (Letters), in pres
Flying by Ear: Blind Flight with a Music-Based Artificial Horizon
Two experiments were conducted in actual flight operations to evaluate an audio artificial horizon display that imposed aircraft attitude information on pilot-selected music. The first experiment examined a pilot's ability to identify, with vision obscured, a change in aircraft roll or pitch, with and without the audio artificial horizon display. The results suggest that the audio horizon display improves the accuracy of attitude identification overall, but differentially affects response time across conditions. In the second experiment, subject pilots performed recoveries from displaced aircraft attitudes using either standard visual instruments, or, with vision obscured, the audio artificial horizon display. The results suggest that subjects were able to maneuver the aircraft to within its safety envelope. Overall, pilots were able to benefit from the display, suggesting that such a display could help to improve overall safety in general aviation
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