3,008 research outputs found
NOISE POLLUTION AND ITS EFFECTS ON HUMAN MENTAL AND PHYSICAL HEALTH
Noise pollution is defined as unwanted sound, capable of causing both mental and physical harm. In order to see if there was a correlation between increasing noise pollution (dB) and (a) increasing Negative Affect Score (NAS), (b) decreasing Positive Affect Score (PAS), and (c) increasing Resting Heart Rate (RHR), research was conducted. Participants were taken to four different testing locations, each with a corresponding dB level, and asked to (a) have their Resting Heart Rate (RHR) taken and (b) fill out a questionnaire based on the Positive and Negative Affect Schedule (PANAS) psychological measure. At the conclusion of this study, it was shown that (a) there was a significant effect of noise pollution (dB) on Negative Affect Score (NAS), (b) there was NOT a significant effect of noise pollution (dB) on Positive Affect Score (PAS), and (c) there was a significant effect of noise pollution (dB) on Resting Heart Rate (RHR). Since this study was limited by different factors (weather conditions, sample size, varying moods, and varying RHR), different steps could be taken to tighten the research design. Overall, due to the small sample size (10), it is not statistically significant enough to draw any concrete conclusions
Transport dynamics of ultracold atoms in a triple-well transistor-like potential
The transport of atoms is experimentally studied in a transistor-like
triple-well potential consisting of a narrow gate well surrounded by source and
drain wells. Atoms are initially loaded into the source well with
pre-determined temperature and chemical potential. Energetic atoms flow from
the source, across the gate, and into the drain where they are removed using a
resonant light beam. The manifestation of atom-atom interactions and
dissipation is evidenced by a rapid population growth in the initially vacant
gate well. The transport dynamics are shown to depend strongly on a feedback
parameter determined by the relative heights of the two barriers forming the
gate region. For a range of feedback parameter values, experiments establish
that the gate atoms develop a larger chemical potential and lower temperature
than those in the source.Comment: 13 pages, 5 figures, accepted for publication in NJ
An Examination of Handling Qualities Criteria for V/STOL Aircraft
A study has been undertaken to define hand-ling qualities criteria for V/STOL aircraft. With the current military requirements for helicopters and airplanes as a framework, modifications and additions were made for conversion to a preliminary set of V/STOL requirements using a broad background of flight experience and pilots' comments from VTOL and STOL aircraft, BLC (boundary-layer-control) equipped aircraft, variable stability aircraft, flight simulators and landing approach studies. The report contains a discussion of the reasoning behind and the sources of information leading to suggested requirements. The results of the study indicate that the majority of V/STOL requirements can be defined by modifications to the helicopter and/or airplane requirements by appropriate definition of reference speeds. Areas where a requirement is included but where the information is felt to be inadequate to establish a firm quantitative requirement include the following: Control power and damping relationships about all axes for various sizes and types of aircraft; control power, sensitivity, d-amping and response for height control; dynamic longitudinal and dynamic lateral- directional stability in the transition region, including emergency operation; hovering steadiness; acceleration and deceleration in transition; descent rates and flight-path angles in steep approaches, and thrust margin for approach
A Look at Handling Qualities of Canard Configurations
The first human-powered flight was achieved by a canard-configured aircraft (Wright Brothers). Although other canard concepts were flown with varying degrees of success over the years, the tail-aft configuration has dominated the aircraft market for both military and civil use. Reviewed are the development of several canard aircraft with emphasis on stability and control, handling qualities, and operating problems. The results show that early canard concepts suffered adversely in flight behavior because of a lack of understanding of the sensitivities of these concepts to basic stability and control principles. Modern canard designs have been made competitive with tail-aft configurations by using appropriate handling qualities design criteria
High-Resolution Imaging and Optical Control of Bose-Einstein Condensates in an Atom Chip Magnetic Trap
A high-resolution projection and imaging system for ultracold atoms is
implemented using a compound silicon and glass atom chip. The atom chip is
metalized to enable magnetic trapping while glass regions enable high numerical
aperture optical access to atoms residing in the magnetic trap about 100
microns below the chip surface. The atom chip serves as a wall of the vacuum
system, which enables the use of commercial microscope components for
projection and imaging. Holographically generated light patterns are used to
optically slice a cigar-shaped magnetic trap into separate regions; this has
been used to simultaneously generate up to four Bose-condensates. Using
fluorescence techniques we have demonstrated in-trap imaging resolution down to
2.5 micronsComment: 4 pages, 5 figures, 12 reference
Flight Measurements of the Flying Qualities of a Lockheed P-80A Airplane (Army No. 44-85099) - Stalling Characteristics
This report contains the flight-test results of the stalling characteristics measured during the flying-qualities investigation of the Lockheed P-8OA airplane (Army No. 44-85099). The tests were conducted in straight and turning flight with and without wing-tip tanks. These tests showed satisfactory stalling characteristics and adequate stall warning for all configurations and conditions tested
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