336 research outputs found
Thruster apparatus and method
A thruster for use with an external power supply. The thruster includes a propellant that exists in a non-gaseous state at standard temperature and pressure and has a melting point Tm, a boiling point Tb, and an evaporation rate. The thruster further includes a reservoir adapted to house the propellant and selectively heated to a temperature greater than Tm and less than Tb, and a power control mechanism positioned to control the amount of power from the external power supply being deposited into the reservoir to control the evaporation rate of the propellant.https://digitalcommons.mtu.edu/patents/1040/thumbnail.jp
Closing the Industry-University Gap through Web-Supported Course Partnerships
This paper discusses a course partnership involving Day & Zimmermann, Inc., a large engineering and professional services company, and Temple University. The course was taught between the months of May and July of 1999 and its main goal was to teach students business process redesign concepts and techniques. These concepts and techniques were used to redesign five real business processes from Day & Zimmermann\u27s information technology organization. Day & Zimmermann\u27s CIO and a senior manager, who played the key role of project manager, championed the course partnership. A Web site with bulletin boards, multimedia components and static content was used to support the partnership. The paper concludes with a set of lessons learned with emphasis on the role of the Web site as an enabler of the course partnership
Empty pews take a financial toll on many US congregations
Most Christian churches were relying heavily on 'collection plates' to pay their bills before the pandemic struck. And less than half were doing any online fundraising as of 2018.Lilly Endowment Inc
Motor Sequence Learning and Consolidation in Unilateral De Novo Patients with Parkinson's Disease
Previous research investigating motor sequence learning (MSL) and consolidation in patients with Parkinson's disease (PD) has predominantly included heterogeneous participant samples with early and advanced disease stages; thus, little is known about the onset of potential behavioral impairments. We employed a multisession MSL paradigm to investigate whether behavioral deficits in learning and consolidation appear immediately after or prior to the detection of clinical symptoms in the tested (left) hand. Specifically, our patient sample was limited to recently diagnosed patients with pure unilateral PD. The left hand symptomatic (LH-S) patients provided an assessment of performance following the onset of clinical symptoms in the tested hand. Conversely, right hand affected (left hand asymptomatic, LH-A) patients served to investigate whether MSL impairments appear before symptoms in the tested hand. LH-S patients demonstrated impaired learning during the initial training session and both LH-S and LH-A patients demonstrated decreased performance compared to controls during the next-day retest. Critically, the impairments in later learning stages in the LH-A patients were evident even before the appearance of traditional clinical symptoms in the tested hand. Results may be explained by the progression of disease-related alterations in relevant corticostriatal networks.status: publishe
How the Median S-Band Circular Polarization Ratio (CPR) of Kilometer-Scale Craters Evolves with Time on the Lunar Maria
No abstract availabl
Games Futures I
Games Futures collect short opinion pieces by industry and research veterans and new voices envisioning possible and desirable futures and needs for games and playable media. This inaugural series features eight of over thirty pieces
Inaugural Editorial: A Lighthouse for Games and Playable Media
In games and playable media, almost nothing is as it was at the turn of the millennium. Digital and analog games have exploded in reach, diversity, and relevance. Digital platforms and globalisation have shifted and fragmented their centres of gravity and how they are made and played. Games are converging with other media, technologies, and arts into a wide field of playable media. Games research has similarly exploded in volume and fragmented into disciplinary specialisms. All this can be deeply disorienting. The journal Games: Research and Practice wants to offer a lighthouse that helps readers orient themselves in this new, ever-shifting reality of games industry and games research
Ariel - Volume 9 Number 1
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Deep ACS Imaging in the Globular Cluster NGC6397: Dynamical Models
We present N-body models to complement deep imaging of the metal-poor
core-collapsed cluster NGC6397 obtained with the Hubble Space Telescope. All
simulations include stellar and binary evolution in-step with the stellar
dynamics and account for the tidal field of the Galaxy. We focus on the results
of a simulation that began with 100000 objects (stars and binaries), 5%
primordial binaries and Population II metallicity. After 16 Gyr of evolution
the model cluster has about 20% of the stars remaining and has reached
core-collapse. We compare the color-magnitude diagrams of the model at this age
for the central region and an outer region corresponding to the observed field
of NGC6397 (about 2-3 half-light radii from the cluster centre). This
demonstrates that the white dwarf population in the outer region has suffered
little modification from dynamical processes - contamination of the luminosity
function by binaries and white dwarfs with non-standard evolution histories is
minimal and should not significantly affect measurement of the cluster age. We
also show that the binary fraction of main-sequence stars observed in the
NGC6397 field can be taken as representative of the primordial binary fraction
of the cluster. For the mass function of the main-sequence stars we find that
although this has been altered significantly by dynamics over the cluster
lifetime, especially in the central and outer regions, that the position of the
observed field is close to optimal for recovering the initial mass function of
the cluster stars (below the current turn-off mass). More generally we look at
how the mass function changes with radius in a dynamically evolved stellar
cluster and suggest where the best radial position to observe the initial mass
function is for clusters of any age.Comment: 34 pages, 11 figures, submitted to AJ, companion paper to 0708.403
The White Dwarf Cooling Sequence of NGC6397
We present the results of a deep Hubble Space Telescope (HST) exposure of the
nearby globular cluster NGC6397, focussing attention on the cluster's white
dwarf cooling sequence. This sequence is shown to extend over 5 magnitudes in
depth, with an apparent cutoff at magnitude F814W=27.6. We demonstrate, using
both artificial star tests and the detectability of background galaxies at
fainter magnitudes, that the cutoff is real and represents the truncation of
the white dwarf luminosity function in this cluster. We perform a detailed
comparison between cooling models and the observed distribution of white dwarfs
in colour and magnitude, taking into account uncertainties in distance,
extinction, white dwarf mass, progenitor lifetimes, binarity and cooling model
uncertainties. After marginalising over these variables, we obtain values for
the cluster distance modulus and age of \mu_0 = 12.02 \pm 0.06 and T_c = 11.47
\pm 0.47Gyr (95% confidence limits). Our inferred distance and white dwarf
initial-final mass relations are in good agreement with other independent
determinations, and the cluster age is consistent with, but more precise than,
prior determinations made using the main sequence turnoff method. In
particular, within the context of the currently accepted \Lambda CDM
cosmological model, this age places the formation of NGC6397 at a redshift z=3,
at a time when the cosmological star formation rate was approaching its peak.Comment: 56 pages, 30 figure
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