4,624 research outputs found
Golden Arm: A Probabilistic Study of Dice Control in Craps
This paper calculates how much control a craps shooter must possess on dice outcomes to eliminate the house advantage. A golden arm is someone who has dice control (or a rhythm roller or dice influencer). There are various strategies for dice control in craps. We discuss several possibilities of dice control that would result in several different mathematical models of control. We do not assert whether dice control is possible or not (there is a lack of published evidence). However, after studying casino-legal methods described by dice-control advocates, we can see only one realistic mathematical model that describes the resulting possible dice control, that in which the four faces on a rotating (horizontal) axis are favored. This is the model that we analyze in this paper
Determinants of Hair Manganese, Lead, Cadmium and Arsenic Levels in Environmentally Exposed Children.
Biomarkers of environmental metal exposure in children are important for elucidating exposure and health risk. While exposure biomarkers for As, Cd, and Pb are relatively well defined, there are not yet well-validated biomarkers of Mn exposure. Here, we measured hair Mn, Pb, Cd, and As levels in children from the Mid-Ohio Valley to determine within and between-subject predictors of hair metal levels. Occipital scalp hair was collected in 2009-2010 from 222 children aged 6-12 years (169 female, 53 male) participating in a study of chemical exposure and neurodevelopment in an industrial region of the Mid-Ohio Valley. Hair samples from females were divided into three two centimeter segments, while males provided a single segment. Hair was cleaned and processed in a trace metal clean laboratory, and analyzed for As, Cd, Mn, and Pb by magnetic sector inductively coupled plasma mass spectrometry. Hair Mn and Pb levels were comparable (median 0.11 and 0.15 µg/g, respectively) and were ~10-fold higher than hair Cd and As levels (0.007 and 0.018 µg/g, respectively). Hair metal levels were higher in males compared to females, and varied by ~100-1000-fold between all subjects, and substantially less (<40-70%) between segments within female subjects. Hair Mn, Pb, and Cd, but not As levels systematically increased by ~40-70% from the proximal to distal hair segments of females. There was a significant effect of season of hair sample collection on hair Mn, Pb, and Cd, but not As levels. Finally, hair metal levels reported here are ~2 to >10-fold lower than levels reported in other studies in children, most likely because of more rigorous hair cleaning methodology used in the present study, leading to lower levels of unresolved exogenous metal contamination of hair
LEVEL OF STRUCTURAL AGGREGATION AND PREDICTIVE ACCURACY OF MILK SUPPLY RESPONSE ESTIMATES
Milk supply response was estimated for Pennsylvania using three different levels of structural aggregation. The base level involved the estimation of milk production in a single equation. Under the second method, production was the product of two equations: milk per cow and number of milk cows. The third method factored production into three equations: milk per cow, number of dairy farms, and number of cows per farm. As expected, the greater the degree of disaggregation the more was learned about the structural aspects of milk production. At the same time, predictive accuracy generally decreased, but the differences among models was slight.Livestock Production/Industries,
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Perceptions of Boston industrial arts teachers concerning the goals, purposes, and future direction of Boston middle schools industrial arts education.
Identifying Student Difficulties with Entropy, Heat Engines, and the Carnot Cycle
We report on several specific student difficulties regarding the Second Law
of Thermodynamics in the context of heat engines within upper-division
undergraduates thermal physics courses. Data come from ungraded written
surveys, graded homework assignments, and videotaped classroom observations of
tutorial activities. Written data show that students in these courses do not
clearly articulate the connection between the Carnot cycle and the Second Law
after lecture instruction. This result is consistent both within and across
student populations. Observation data provide evidence for myriad difficulties
related to entropy and heat engines, including students' struggles in reasoning
about situations that are physically impossible and failures to differentiate
between differential and net changes of state properties of a system. Results
herein may be seen as the application of previously documented difficulties in
the context of heat engines, but others are novel and emphasize the subtle and
complex nature of cyclic processes and heat engines, which are central to the
teaching and learning of thermodynamics and its applications. Moreover, the
sophistication of these difficulties is indicative of the more advanced
thinking required of students at the upper division, whose developing knowledge
and understanding give rise to questions and struggles that are inaccessible to
novices
Photolytically generated aerosols in the mesosphere and thermosphere of Titan
Analysis of the Cassini Ultraviolet Imaging Spectrometer (UVIS) stellar and
solar occultations at Titan to date include 12 species: N (nitrogen),
CH (methane), CH (acetylene), CH (ethylene),
CH (ethane), CH (diacetylene), CH
(benzene), CN (dicyanodiacetylene), CN (cyanogen), HCN
(hydrogen cyanide), HCN (cyanoacetylene), and aerosols distinguished by a
structureless continuum extinction (absorption plus scattering) of photons in
the EUV. The introduction of aerosol particles, retaining the same refractive
index properties as tholin with radius 125 \AA and using Mie theory,
provides a satisfactory fit to the spectra. The derived vertical profile of
aerosol density shows distinct structure, implying a reactive generation
process reaching altitudes more than 1000 km above the surface. A photochemical
model presented here provides a reference basis for examining the chemical and
physical processes leading to the distinctive atmospheric opacity at Titan. We
find that dicyanodiacetylene is condensable at 650 km, where the
atmospheric temperature minimum is located. This species is the simplest
molecule identified to be condensable. Observations are needed to confirm the
existence and production rates of dicyanodiacetylene.Comment: A typo in Table 1 was made in the previous version. The corrected
tholin abundance is 4.6x10^11. ApJL in press. Will be published on June 1st,
or May 21 onlin
Heavy ion induced Single Event Phenomena (SEP) data for semiconductor devices from engineering testing
The accumulation of JPL data on Single Event Phenomena (SEP), from 1979 to August 1986, is presented in full report format. It is expected that every two years a supplement report will be issued for the follow-on period. This data for 135 devices expands on the abbreviated test data presented as part of Refs. (1) and (3) by including figures of Single Event Upset (SEU) cross sections as a function of beam Linear Energy Transfer (LET) when available. It also includes some of the data complied in the JPL computer in RADATA and the SPACERAD data bank. This volume encompasses bipolar and MOS (CMOS and MHNOS) device data as two broad categories for both upsets (bit-flips) and latchup. It also includes comments on less well known phenomena, such as transient upsets and permanent damage modes
Nonpublication in the Eleventh Circuit: An Empirical Analysis
This Article examines the criteria used by the Eleventh Circuit Court of Appeals in determining whether or not a judicial opinion should be published. Through an empirical study and analysis, the authors conclude that the written rule governing publication offers little guidance to the judges and is often applied inconsistently within the circuit
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