3,225 research outputs found
Post-operative cranial pressure monitoring system
System for monitoring of fluidic pressures in cranial cavity uses a miniaturized pressure sensing transducer, combined with suitable amplification means, a meter with scale calibrated in terms of pressures between minus 100 and plus 900 millimeters of water, and a miniaturized chart recorder covering similar range of pressures
A Case for Auditing Strategic Information Systems
Business strategy represents the choice of how to compete for competitive advantage (Porter, 1980, Porter, 1985). And Strategic Information Systems (SIS) shape (Rackoff et al., 1985, Wiseman, 1985) and enable (Bensaou and Venkatraman, 1995) that business strategy. SIS has been the focus of a large body of research and anecdotal descriptions (Chan and Huff, 1992, Porter and Millar, 1985, Wiseman, 1985, Ghosh, 1998, Magretta, 1998, Shapiro and Varian, 1999). There may be as few as 1.5 thousand PhD degree-holding researchers in Management Information Systems or Business Data Processing fields, while we may place the number of accountants and auditors (including Certified Information Systems Auditors or CISAs) closer to 1.2 million. In order to determine whether specific configurations of information technology reasonably implement the premises of a firm’s competitive strategy, we think the SIS literature is mature enough to support CISAs compiling competent and sufficient evidential matter supporting certain frameworks, constructs and measurements described in the business strategy literature
Discovery of a Visual T-Dwarf Triple System and Binarity at the L/T Transition
We present new high contrast imaging of 8 L/T transition brown dwarfs using
the NIRC2 camera on the Keck II telescope. One of our targets, the T3.5 dwarf
2MASS J08381155 + 1511155, was resolved into a hierarchal triple with projected
separations of 2.5+/-0.5 AU and 27+/-5 AU for the BC and A(BC) components
respectively. Resolved OSIRIS spectroscopy of the A(BC) components confirm that
all system members are T dwarfs. The system therefore constitutes the first
triple T-dwarf system ever reported. Using resolved photometry to model the
integrated-light spectrum, we infer spectral types of T3, T3, and T4.5 for the
A, B, and C components respectively. The uniformly brighter primary has a bluer
J-Ks color than the next faintest component, which may reflect a sensitive
dependence of the L/T transition temperature on gravity, or alternatively
divergent cloud properties amongst components. Relying on empirical trends and
evolutionary models we infer a total system mass of 0.034-0.104 Msun for the BC
components at ages of 0.3-3 Gyr, which would imply a period of 12-21 yr
assuming the system semi-major axis to be similar to its projection. We also
infer differences in effective temperatures and surface gravities between
components of no more than ~150 K and ~0.1 dex. Given the similar physical
properties of the components, the 2M0838+15 system provides a controlled sample
for constraining the relative roles of effective temperature, surface gravity,
and dust clouds in the poorly understood L/T transition regime. Combining our
imaging survey results with previous work we find an observed binary fraction
of 4/18 or 22_{-8}^{+10}% for unresolved spectral types of L9-T4 at separations
>~0.1 arcsec. This translates into a volume-corrected frequency of
13^{-6}_{+7}%, which is similar to values of ~9-12% reported outside the
transition. (ABRIDGED)Comment: Accepted for publication in the Astrophysical Journal. 23 pages, 12
figure
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