The Voluntary Adjustment of Railroad Obligations

Automatic memory management techniques eliminate many programming errors that are both hard to find and to correct. However, these techniques are not yet used in embedded systems with hard realtime applications. The reason is that current methods for automatic memory management have a number of drawbacks. The two major ones are: (1) not being able to always guarantee short real-time deadlines and (2) using large amounts of extra memory. Memory is usually a scarce resource in embedded applications. In this paper we present a new technique, Real-Time Reference Counting (RTRC) that overcomes the current problems and makes automatic memory management attractive also for hard real-time applications. The main contribution of RTRC is that often all memory can be used to store live objects. This should be compared to a memory overhead of about 500% for garbage collectors based on copying techniques and about 50% for garbage collectors based on mark-and-sweep techniques

Composition Conditions for Classes of Analytic Functions

We prove that for classes of analytic functions tree composition condition and composition condition coincide.Comment: 13 page

Cost Shared Wildfire Risk Mitigation in Log Hill Mesa, Colorado: Survey Evidence on Participation and Willingness to Pay

Wildland–urban interface (WUI) homeowners who do not mitigate the wildfire risk on their properties impose a negative externality on society. To reduce the social costs of wildfire and incentivise homeowners to take action, cost sharing programs seek to reduce the barriers that impede wildfire risk mitigation. Using survey data from a WUI community in western Colorado and a two-stage decision framework, we examine residents’ willingness to participate in a cost sharing program for removing vegetation on their properties and the amount they are willing to contribute to the cost of that removal. Wefind that different factors motivate decisions about participation and about how much to pay. Willingness to participate correlates with both financial and non-monetary considerations, including informational barriers and wildfire risk perceptions, but not with concerns about effectiveness or visual impacts. Residents of properties with higher wildfire risk levels are less likely to participate in the cost sharing than those with lower levels of wildfire risk. We find widespread, positive willingness to pay for vegetation removal, with the amount associated negatively with property size and positively with respondent income. These results can inform the development of cost sharing programs to encourage wildfire risk mitigation on private property

Spectropolarimetric Evidence for Radiatively Inefficient Accretion in an Optically Dull Active Galaxy

We present Subaru/FOCAS spectropolarimetry of two active galaxies in the Cosmic Evolution Survey. These objects were selected to be optically dull, with the bright X-ray emission of an AGN but missing optical emission lines in our previous spectroscopy. Our new observations show that one target has very weak emission lines consistent with an optically dull AGN, while the other object has strong emission lines typical of a host-diluted Type 2 Seyfert galaxy. In neither source do we observe polarized emission lines, with 3-sigma upper limits of P_BLR < 2%. This means that the missing broad emission lines (and weaker narrow emission lines) are not due to simple anisotropic obscuration, e.g., by the canonical AGN torus. The weak-lined optically dull AGN exhibits a blue polarized continuum with P = 0.78 +/- 0.07% at 4400 A < lambda_rest < 7200 A (P = 1.37 +/- 0.16% at 4400 A < lambda_rest < 5050 A). The wavelength dependence of this polarized flux is similar to that of an unobscured AGN continuum and represents the intrinsic AGN emission, either as synchrotron emission or the outer part of an accretion disk reflected by a clumpy dust scatterer. Because this intrinsic AGN emission lacks emission lines, this source is likely to have a radiatively inefficient accretion flow.Comment: Accepted to ApJ. 6 pages, 2 figure

Comparison of a nurse initiated insulin infusion protocol for intensive insulin therapy between adult surgical trauma, medical and coronary care intensive care patients

<p>Abstract</p> <p>Background</p> <p>Sustained hyperglycemia is a known risk factor for adverse outcomes in critically ill patients. The specific aim was to determine if a nurse initiated insulin infusion protocol (IIP) was effective in maintaining blood glucose values (BG) within a target goal of 100–150 mg/dL across different intensive care units (ICUs) and to describe glycemic control during the 48 hours after protocol discontinuation.</p> <p>Methods</p> <p>A descriptive, retrospective review of 366 patients having 28,192 blood glucose values in three intensive care units, Surgical Trauma Intensive Care Unit (STICU), Medical (MICU) and Coronary Care Unit (CCU) in a quaternary care hospital was conducted. Patients were > 15 years of age, admitted to STICU (n = 162), MICU (n = 110) or CCU (n = 94) over 8 months; October 2003-June 2004 and who had an initial blood glucose level > 150 mg/dL. We summarized the effectiveness and safety of a nurse initiated IIP, and compared these endpoints among STICU, MICU and CCU patients.</p> <p>Results</p> <p>The median blood glucose values (mg/dL) at initiation of insulin infusion protocol were lower in STICU (188; IQR, 162–217) than in MICU, (201; IQR, 170–268) and CCU (227; IQR, 178–313); <it>p </it>< 0.0001. Mean time to achieving a target glucose level (100–150 mg/dL) was similar between the three units: 4.6 hours in STICU, 4.7 hours in MICU and 4.9 hours in CCU (<it>p </it>= 0.27). Hypoglycemia (BG < 60 mg/dL) occurred in 7% of STICU, 5% of MICU, and 5% of CCU patients (<it>p </it>= 0.85). Protocol violations were uncommon in all three ICUs. Mean blood glucose 48 hours following IIP discontinuation was significantly different for each population: 142 mg/dL in STICU, 167 mg/dL in MICU, and 160 mg/dL in CCU (<it>p </it>< 0.0001).</p> <p>Conclusion</p> <p>The safety and effectiveness of nurse initiated IIP was similar across different ICUs in our hospital. Marked variability in glucose control after the protocol discontinuation suggests the need for further research regarding glucose control in patients transitioning out of the ICU.</p

Accretion Rate and the Physical Nature of Unobscured Active Galaxies

We show how accretion rate governs the physical properties of a sample of unobscured broad-line, narrow-line, and lineless active galactic nuclei (AGNs). We avoid the systematic errors plaguing previous studies of AGN accretion rate by using accurate accretion luminosities (L_int) from well-sampled multiwavelength SEDs from the Cosmic Evolution Survey (COSMOS), and accurate black hole masses derived from virial scaling relations (for broad-line AGNs) or host-AGN relations (for narrow-line and lineless AGNs). In general, broad emission lines are present only at the highest accretion rates (L_int/L_Edd > 0.01), and these rapidly accreting AGNs are observed as broad-line AGNs or possibly as obscured narrow-line AGNs. Narrow-line and lineless AGNs at lower specific accretion rates (L_int/L_Edd < 0.01) are unobscured and yet lack a broad line region. The disappearance of the broad emission lines is caused by an expanding radiatively inefficient accretion flow (RIAF) at the inner radius of the accretion disk. The presence of the RIAF also drives L_int/L_Edd < 10^-2 narrow-line and lineless AGNs to 10 times higher ratios of radio to optical/UV emission than L_int/L_Edd > 0.01 broad-line AGNs, since the unbound nature of the RIAF means it is easier to form a radio outflow. The IR torus signature also tends to become weaker or disappear from L_int/L_Edd < 0.01 AGNs, although there may be additional mid-IR synchrotron emission associated with the RIAF. Together these results suggest that specific accretion rate is an important physical "axis" of AGN unification, described by a simple model.Comment: Accepted for publication in the Astrophysical Journal. 15 pages, 9 figure

Berkeley Supernova Ia Program I: Observations, Data Reduction, and Spectroscopic Sample of 582 Low-Redshift Type Ia Supernovae

In this first paper in a series we present 1298 low-redshift (z\leq0.2) optical spectra of 582 Type Ia supernovae (SNe Ia) observed from 1989 through 2008 as part of the Berkeley SN Ia Program (BSNIP). 584 spectra of 199 SNe Ia have well-calibrated light curves with measured distance moduli, and many of the spectra have been corrected for host-galaxy contamination. Most of the data were obtained using the Kast double spectrograph mounted on the Shane 3 m telescope at Lick Observatory and have a typical wavelength range of 3300-10,400 Ang., roughly twice as wide as spectra from most previously published datasets. We present our observing and reduction procedures, and we describe the resulting SN Database (SNDB), which will be an online, public, searchable database containing all of our fully reduced spectra and companion photometry. In addition, we discuss our spectral classification scheme (using the SuperNova IDentification code, SNID; Blondin & Tonry 2007), utilising our newly constructed set of SNID spectral templates. These templates allow us to accurately classify our entire dataset, and by doing so we are able to reclassify a handful of objects as bona fide SNe Ia and a few other objects as members of some of the peculiar SN Ia subtypes. In fact, our dataset includes spectra of nearly 90 spectroscopically peculiar SNe Ia. We also present spectroscopic host-galaxy redshifts of some SNe Ia where these values were previously unknown. [Abridged]Comment: 34 pages, 11 figures, 11 tables, revised version, re-submitted to MNRAS. Spectra will be released in January 2013. The SN Database homepage (http://hercules.berkeley.edu/database/index_public.html) contains the full tables, plots of all spectra, and our new SNID template