17,522 research outputs found
Development of anlytical techniques for hydrocarbons in mineral aggregates quarterly status report no. 4, jul. - sep. 1964
Chemical analysis of rock and meteorite samples for hydrocarbon conten
Six-degree-of-freedom program to optimize simulated trajectories (6D POST). Volume 1: Formulation manual
The basic equations and models used in a computer program (6D POST) to optimize simulated trajectories with six degrees of freedom were documented. The 6D POST program was conceived as a direct extension of the program POST, which dealt with point masses, and considers the general motion of a rigid body with six degrees of freedom. It may be used to solve a wide variety of atmospheric flight mechanics and orbital transfer problems for powered or unpowered vehicles operating near a rotating oblate planet. Its principal features are: an easy to use NAMELIST type input procedure, an integrated set of Flight Control System (FCS) modules, and a general-purpose discrete parameter targeting and optimization capability. It was written in FORTRAN 4 for the CDC 6000 series computers
Considerations Concerning the Radiative Corrections to Muon Decay in the Fermi and Standard Theories
The FAC, PMS, and BLM optimization methods are applied to the QED corrections
to the muon lifetime in the Fermi V-A theory. The FAC and PMS scales are close
to m_e, while the BLM scale nearly concides with the geometric average
\sqrt{m_e m_\mu}. The optimized expressions are employed to estimate the third
order coefficient in the \alpha(m_\mu) expansion and the theoretical error of
the perturbative series. Using arguments based on effective field theory and a
simple examination of Feynman diagrams, it is shown that, if contributions of
O(\alpha m_\mu^2/M_W^2) are neglected, the corrections to muon decay in the SM
factorize into the QED correction of the Fermi V-A theory and the electroweak
amplitude g^2/(1-\Delta r), both of which are strictly scale-independent. We
use the results to clarify how the QED corrections to muon decay and the Fermi
constant G_F should be used in the SM, and what is the natural choice of scales
if running couplings are employed.Comment: 11 pages, latex, no figures To be published in Nucl. Phys.
A New Medicare End-of-Life Benefit for Nursing Home Residents
A new Medicare benefit is needed to support end-of-life care for those spending their final days in a nursing home, say the authors of this article. Arguing that the current hospice benefit is a poor fit with the nursing home setting, the authors recommend a new benefit that would enable nursing home residents to receive individualized palliative and psychosocial services in addition to rehabilitative services
Relating Physical Observables in QCD without Scale-Scheme Ambiguity
We discuss the St\"uckelberg-Peterman extended renormalization group
equations in perturbative QCD, which express the invariance of physical
observables under renormalization-scale and scheme-parameter transformations.
We introduce a universal coupling function that covers all possible choices of
scale and scheme. Any perturbative series in QCD is shown to be equivalent to a
particular point in this function. This function can be computed from a set of
first-order differential equations involving the extended beta functions. We
propose the use of these evolution equations instead of perturbative series for
numerical evaluation of physical observables. This formalism is free of
scale-scheme ambiguity and allows a reliable error analysis of higher-order
corrections. It also provides a precise definition for as the pole in the associated 't Hooft scheme. A concrete application to
is presented.Comment: Plain TEX, 4 figures (available upon request), 22 pages,
DOE/ER/40322-17
Concept design and alternate arrangements of orbiter mid-deck habitability features
The evaluations and recommendations for habitability features in the space shuttle orbiter mid-deck are summarized. The orbiter mission plans, the mid-deck dimensions and baseline arrangements along with crew compliments and typical activities were defined. Female and male anthropometric data based on zero-g operations were also defined. Evaluations of baseline and alternate feasible concepts provided several recommendations which are discussed
Fabrication of free-standing ordered fluorescent polymer nanofibres by electrospinning
The authors are grateful to the Engineering and Physical Sciences Research Council for financial support.We demonstrate a static fabrication approach to make free-standing ordered arrays of fluorescent nanofibres through control of the transverse electrospinning field. The alignment and the density of the nanofibre arrays are optimised by careful design of both the source and collector electrode geometries which can control the transverse electric field over the full path of the jet. In doing so, we fabricate suspended fluorescent nanofibres with an aspect ratio of 10(4), and with a substantially increased density and order parameter (by a factor of similar to 10 compared to random deposition). Electrostatic modelling suggests that the field distribution of the component is the main contribution to the ordering between the plates. This method offers increased efficiency for the creation of ordered fibres collected over a small area and the characterisation of their photoluminescent properties.Publisher PDFPeer reviewe
Application of High Order Acoustic Finite Elements to Transmission Losses and Enclosure Problems
A family of acoustic finite elements was developed based on C continuity (acoustic pressure being the nodal variable) and the no-flow condition. The family include triangular, quadrilateral and hexahedral isoparametric elements with linear quadratic and cubic variation in modelling and distortion. Of greatest use in problems with irregular boundaries are the cubic isoparametric elements: the 32 node hexahedral element for three-dimensional systems; and the twelve node quadrilateral and ten node triangular elements for two-dimensional/axisymmetric applications. These elements were applied to problems involving cavity resonances, transmission loss in silencers and the study of end effects, using a Floating Point Systems 164 attached array processor accessed through an Amdahl 5860 mainframe. The elements are presently being used to study the end effects associated with duct terminations within finite enclosures. The transmission losses with various silencers and sidebranches in ducts is also being studied using the same elements
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