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Interface temperatures in friction braking
YesResults and analysis from investigations into the behaviour of the interfacial layer (Tribolayer)
at the friction interface of a brake friction pair (resin bonded composite friction material
and cast iron rotor) are presented in which the disc/pad interface temperature has been
measured using thermocouple methods. Using a designed experiment approach, the interface
temperature is shown to be affected by factors including the number of braking applications,
the friction coefficient, sliding speed, braking load and friction material. The time-dependent
nature of the Tribo-Iayer formation and the real contact area distribution are shown to be
causes of variation in interface temperatures in friction braking. The work extends the
scientific understanding of interface contact and temperature during friction braking
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Effect of transient event frequency content and scale on the human detection of road surface type
This paper describes two laboratory-based experiments which evaluate the effect of transient event frequency
content and scale on the human detection of road surface type by means of steering wheel vibration. This study
used steering wheel tangential direction acceleration time histories which had been measured in a mid-sized
European automobile that was driven over two different types of road surface. The steering acceleration stimuli
were manipulated by means of the mildly non-stationary mission synthesis (MNMS) algorithm in order to
produce test stimuli which were selectively modified in terms of the number, and size, of transient vibration
events they contained. Fifteen test participants were exposed to both unmanipulated and manipulated steering
wheel rotational stimuli by means of a steering wheel vibration simulator. For each road surface type a total of
45 vibration test stimuli were presented to each participant. Each participant was asked to state, by means of a
simple "yes" or "no" answer, whether each individual stimuli was from a road surface which was being
presented in front of the simulator as a picture on a large board. Using Signal Detection Theory as the
analytical framework the results were summarized by means of the detectability index d' and by means of
receiver operating curve (ROC) points. Improvements of up to 20 percentage points in the rate of correct
detection were achieved by means of selective manipulation of the steering vibration stimuli. The results
suggested that no single setting of the MNMS algorithm proved optimal for both two road surface types that
were investigated
The effect of short-term changes in air pollution on respiratory and cardiovascular morbidity in Nicosia, Cyprus.
Presented at the 6th International Conference on Urban Air Quality, Limassol, March, 2007. Short-paper was submitted for peer-review and appears in proceedings of the conference.This study investigates the effect of daily changes in levels of PM10 on the daily volume of respiratory and cardiovascular
admissions in Nicosia, Cyprus during 1995-2004. After controlling for long- (year and month) and short-term (day of the
week) patterns as well as the effect of weather in Generalized Additive Poisson models, some positive associations were
observed with all-cause and cause-specific admissions. Risk of hospitalization increased stepwise across quartiles of days with
increasing levels of PM10 by 1.3% (-0.3, 2.8), 4.9% (3.3, 6.6), 5.6% (3.9, 7.3) as compared to days with the lowest
concentrations. For every 10μg/m3 increase in daily average PM10 concentration, there was a 1.2% (-0.1%, 2.4%) increase in
cardiovascular admissions. With respects to respiratory admissions, an effect was observed only in the warm season with a
1.8% (-0.22, 3.85) increase in admissions per 10μg/m3 increase in PM10. The effect on respiratory admissions seemed to be
much stronger in women and, surprisingly, restricted to people of adult age
NASA SBIR abstracts of 1990 phase 1 projects
The research objectives of the 280 projects placed under contract in the National Aeronautics and Space Administration (NASA) 1990 Small Business Innovation Research (SBIR) Phase 1 program are described. The basic document consists of edited, non-proprietary abstracts of the winning proposals submitted by small businesses in response to NASA's 1990 SBIR Phase 1 Program Solicitation. The abstracts are presented under the 15 technical topics within which Phase 1 proposals were solicited. Each project was assigned a sequential identifying number from 001 to 280, in order of its appearance in the body of the report. The document also includes Appendixes to provide additional information about the SBIR program and permit cross-reference in the 1990 Phase 1 projects by company name, location by state, principal investigator, NASA field center responsible for management of each project, and NASA contract number
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