2,444 research outputs found
Restraint Stress and Strain in Circular Patch Welds(Mechanics, Strength & Structural Design)
A variational perturbation scheme for many-particle systems in the functional integral approach
A variational Perturbation theory based on the functional integral approach
is formulated for many-particle systems. Using the variational action obtained
through Jensen-Peierls' inequality, a perturbative expansion scheme for the
thermodynamic potential is established. A modified Wick's theorem is obtained
for the variational perturbation expansions. This theorem allows one to carry
out systematic calculations of higher order terms without worrying about the
double counting problem. A model numerical calculation was carried out on a
nucleon gas system interacting through the Yukawa-type potential to test the
efficiency of the present method.Comment: accepted for publication in Phys. Rev.
Rayleigh-Schroedinger-Goldstone variational perturbation theory for many fermion systems
We present a Rayleigh-Schroedinger-Goldstone perturbation formalism for many
fermion systems. Based on this formalism, variational perturbation scheme which
goes beyond the Gaussian approximation is developed. In order to go beyond the
Gaussian approximation, we identify a parent Hamiltonian which has an effective
Gaussian vacuum as a variational solution and carry out further perturbation
with respect to the renormalized interaction using Goldstone's expansion.
Perturbation rules for the ground state wavefunctional and energy are found.
Useful commuting relations between operators and the Gaussian wavefunctional
are also found, which could reduce the calculational efforts substantially. As
examples, we calculate the first order correction to the Gaussian
wavefunctional and the second order correction to the ground state of an
electron gas system with the Yukawa-type interaction.Comment: 11pages, 1figur
A Study on Virtual Reality Storytelling by Story Authoring Tool Algorithm
The objective of this study was to examine the storytelling principles of virtual reality contents, which are recently
grabbing much attention, and the patterns of their generation rules and, based on the results, to analyze the elements and
structure of a storytelling method suitable for virtual reality contents. In virtual reality environment, a story is usually
being generated between choices made by a user who behaves autonomously under simulated environmental factors and
the environmental constraints. This corresponds to a mutually complementary role of representation and simulation,
which has been hotly discussed in the field of interactive storytelling. This study was conducted based on the assumption
that such a mutually complementary realization is ideal for virtual reality storytelling. A simulation-based story authoring
tool is a good example that shows this mutual complementation, in that it develops a story through various algorithms
which involves the interaction of agents which occur within the strata of a virtual environment. Therefore, it can be a
methodology for virtual reality storytelling. The structures and elements of narratives used in virtual reality storytelling
which achieve balance of representation and simulation are much similar to an algorithm strategy of a simulation-based
story authoring tool. The virtual reality contents released up to now can be classified into four categories based on the
two axes of representation and simulation. The study focused on contents which are layered in higher strata of both
representation and simulation. In the perspective of representation strata, these contents are actively using such elements
as goal, event, action, perception, internal element, outcome, and setting element, which are constituents of ‘Fabula
model’, to generate time relations and cause-effect relations. And in the perspective of simulation strata, the use of the
‘Late commitment’ strategy allowed users to understand the meanings of their actions taken during the process of
experimenting with various dynamic principles within the environment
Analytical Calculation Method of Restraint Stresses and Strains due to Slit Weld in Rectangular Plates(WELDING MECHANICS, STRENGTH AND DESIGN)
Safety Evaluation of Cruciform Columns Corrected by Heating(Mechanics, Strength & Structural Design)
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