194 research outputs found
The Perfect Binary One-Error-Correcting Codes of Length 15: Part I--Classification
A complete classification of the perfect binary one-error-correcting codes of
length 15 as well as their extensions of length 16 is presented. There are 5983
such inequivalent perfect codes and 2165 extended perfect codes. Efficient
generation of these codes relies on the recent classification of Steiner
quadruple systems of order 16. Utilizing a result of Blackmore, the optimal
binary one-error-correcting codes of length 14 and the (15, 1024, 4) codes are
also classified; there are 38408 and 5983 such codes, respectively.Comment: 6 pages. v3: made the codes available in the source of this pape
Quantum Spin Dynamics (QSD) II
We continue here the analysis of the previous paper of the Wheeler-DeWitt
constraint operator for four-dimensional, Lorentzian, non-perturbative,
canonical vacuum quantum gravity in the continuum. In this paper we derive the
complete kernel, as well as a physical inner product on it, for a non-symmetric
version of the Wheeler-DeWitt operator. We then define a symmetric version of
the Wheeler-DeWitt operator. For the Euclidean Wheeler-DeWitt operator as well
as for the generator of the Wick transform from the Euclidean to the Lorentzian
regime we prove existence of self-adjoint extensions and based on these we
present a method of proof of self-adjoint extensions for the Lorentzian
operator. Finally we comment on the status of the Wick rotation transform in
the light of the present results.Comment: 27 pages, Latex, preceded by a companion paper before this on
QSD IV : 2+1 Euclidean Quantum Gravity as a model to test 3+1 Lorentzian Quantum Gravity
The quantization of Lorentzian or Euclidean 2+1 gravity by canonical methods
is a well-studied problem. However, the constraints of 2+1 gravity are those of
a topological field theory and therefore resemble very little those of the
corresponding Lorentzian 3+1 constraints. In this paper we canonically quantize
Euclidean 2+1 gravity for arbitrary genus of the spacelike hypersurface with
new, classically equivalent constraints that maximally probe the Lorentzian 3+1
situation. We choose the signature to be Euclidean because this implies that
the gauge group is, as in the 3+1 case, SU(2) rather than SU(1,1). We employ,
and carry out to full completion, the new quantization method introduced in
preceding papers of this series which resulted in a finite 3+1 Lorentzian
quantum field theory for gravity. The space of solutions to all constraints
turns out to be much larger than the one as obtained by traditional approaches,
however, it is fully included. Thus, by suitable restriction of the solution
space, we can recover all former results which gives confidence in the new
quantization methods. The meaning of the remaining "spurious solutions" is
discussed.Comment: 35p, LATE
QSD VI : Quantum Poincar\'e Algebra and a Quantum Positivity of Energy Theorem for Canonical Quantum Gravity
We quantize the generators of the little subgroup of the asymptotic
Poincar\'e group of Lorentzian four-dimensional canonical quantum gravity in
the continuum. In particular, the resulting ADM energy operator is densely
defined on an appropriate Hilbert space, symmetric and essentially
self-adjoint. Moreover, we prove a quantum analogue of the classical positivity
of energy theorem due to Schoen and Yau. The proof uses a certain technical
restriction on the space of states at spatial infinity which is suggested to us
given the asymptotically flat structure available. The theorem demonstrates
that several of the speculations regarding the stability of the theory,
recently spelled out by Smolin, are false once a quantum version of the
pre-assumptions underlying the classical positivity of energy theorem is
imposed in the quantum theory as well. The quantum symmetry algebra
corresponding to the generators of the little group faithfully represents the
classical algebra.Comment: 24p, LATE
歩行速度と最大一歩幅,ファンクショナルリーチの関連
The purpose of this study was to clarify the relationship of walking speed to
physical fitness. Eleven healthy young men (19 to 21 years of age) and ten
healthy elderly men (69 to 84 years of age) participated as the subjects in this
study. The physical fitness element was estimated by measuring the maximum
one step length of the lower limb muscle and the functional reach test of
the balance function. The following results were obtained:
1. The grip strength, maximum one step length, maximum one step
length / lower limb length, functional reach, functional reach / height and one-leg
standing with eyes open were all significantly smaller for the elderly;
2. The free walking speed for the elderly was measured to be faster for those
more physically fit. However, for the young adults physical fitness had less correlation
to free walking speed;
3. The step length of the maximum speed of walking of young adults did not
correlate to the maximum one step length. However, for the elderly, there was
a correlation to the step length of the maximum speed of walking and the maxi
mum one step length;
4. The walking ability of the elderly affected the muscle strength of the lower
limb more than the upper limb.
Therefore, the results conclude that in looking at the free walking and maximum
speed of walking, the elderly had a higher correlation between their walking
speed to their lower limb muscle and balance ability while the walking speed
of young adults was determined by not only muscle strength and balance ability,
but also from other element
Adaptive projective lag synchronization of uncertain complex dynamical networks with delay coupling
Characterization of autonomous Dart1 transposons belonging to the hAT superfamily in rice
An endogenous 0.6-kb rice DNA transposon, nDart1-0, was found as an active nonautonomous element in a mutable virescent line, pyl-v, displaying leaf variegations. Here, we demonstrated that the active autonomous element aDart in pyl-v corresponds to Dart1-27 on chromosome 6 in Nipponbare, which carries no active aDart elements, and that aDart and Dart1-27 are identical in their sequences and chromosomal locations, indicating that Dart1-27 is epigenetically silenced in Nipponbare. The identification of aDart in pyl-v was first performed by map-based cloning and by detection of the accumulated transposase transcripts. Subsequently, various transposition activities of the cloned Dart1-27 element from Nipponbare were demonstrated in Arabidopsis. Dart1-27 in Arabidopsis was able to excise nDart1-0 and Dart1-27 from cloned sites, generating footprints, and to integrate into new sites, generating 8-bp target site duplications. In addition to Dart1-27, Nipponbare contains 37 putative autonomous Dart1 elements because their putative transposase genes carry no apparent nonsense or frameshift mutations. Of these, at least four elements were shown to become active aDart elements in transgenic Arabidopsis plants, even though considerable sequence divergence arose among their transposases. Thus, these four Dart1 elements and Dart1-27 in Nipponbare must be potential autonomous elements silenced epigenetically. The regulatory and evolutionary implications of the autonomous Dart1 elements and the development of an efficient transposon-tagging system in rice are discussed
Effect of sonic versus ultrasonic activation on aqueous solution penetration in root canal dentin.
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