76,318 research outputs found
Computation of group table alphanumeric display
Computer program, using only group elements as input data, provides machine computation of group tables used for proving theorems and algorithms of finite groups. Program is written for second generation computers
Irreversibility time scale
Entropy creation rate is introduced for a system interacting with thermostats
({\it i.e.}, in the usual language, for a system subject to internal
conservative forces interacting with ``external'' thermostats via conservative
forces) and a fluctuation theorem for it is proved. As an application a time
scale is introduced, to be interpreted as the time over which irreversibility
becomes manifest in a process leading from an initial to a final stationary
state of a mechanical system in a general nonequilibrium context. The time
scale is evaluated in a few examples, including the classical Joule-Thompson
process (gas expansion in a vacuum).
The new version (n.2) contains several comments on references pointed out to
me after posting the version n.1.Comment: 6 pages 1 figur
FORTRAN 4 program for computation of group tables of finite groups - Program for second generation machines
FORTRAN 4 program for second generation machines for computing group tables of finite group
FORTRAN program for computation of group table-alphanumeric display
FORTRAN program for computation of group tables, alphanumeric displa
Multistage multiple-reentry turbine Patent
Multistage, multiple reentry, single rotor, axial flow turbin
Applicability of advanced automotive heat engines to solar thermal power
The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program
Multistage multiple-reentry turbine Patent
Multistage multiple reentry axial flow reaction turbine with reverse flow reentry ductin
Note on nonequilibrium stationary states and entropy
In transformations between nonequilibrium stationary states, entropy might be
a not well defined concept. It might be analogous to the ``heat content'' in
transformations in equilibrium which is not well defined either, if they are
not isochoric ({\it i.e.} do involve mechanical work). Hence we conjecture that
un a nonequilbrium stationary state the entropy is just a quantity that can be
transferred or created, like heat in equilibrium, but has no physical meaning
as ``entropy content'' as a property of the system.Comment: 4 page
FORTRAN program for machine computation of group tables of finite groups
FORTRAN program for computation of finite group table
Adaptive high-order finite element solution of transient elastohydrodynamic lubrication problems
This article presents a new numerical method to solve transient line contact elastohydrodynamic lubrication (EHL) problems. A high-order discontinuous Galerkin (DG) finite element method is used for the spatial discretization, and the standard Crank-Nicolson method is employed to approximate the time derivative. An h-adaptivity method is used for grid adaptation with the time-stepping, and the penalty method is employed to handle the cavitation condition.
The roughness model employed here is a simple indentation, which is located on the upper surface. Numerical results are presented comparing the DG method to standard finite difference (FD) techniques. It is shown that micro-EHL features are captured with far fewer degrees of freedom than when using low-order FD methods
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