4,517 research outputs found
ON SMARANDACHE RINGS
It is proved that a ring R in which for every x ∈ R there exists a (and hence
the smallest) natural number n(x) > 1 such that xn(x) = x is always a Smarandache
Ring. Two examples are provided for justification
(Anti-)chiral Superfield Approach to Nilpotent Symmetries: Self-Dual Chiral Bosonic Theory
We exploit the beauty and strength of the symmetry invariant restrictions on
the (anti-)chiral superfields to derive the Becchi-Rouet-Stora-Tyutin (BRST),
anti-BRST and (anti-)co-BRST symmetry transformations in the case of a two
(1+1)-dimensional (2D) self-dual chiral bosonic field theory within the
framework of augmented (anti-)chiral superfield formalism. Our 2D ordinary
theory is generalized onto a (2, 2)-dimensional supermanifold which is
parameterized by the superspace variable Z^M = (x^\mu, \theta, \bar\theta)
where x^\mu (with \mu = 0, 1) are the ordinary 2D bosonic coordinates and
(\theta,\, \bar\theta) are a pair of Grassmannian variables with their standard
relationships: \theta^2 = {\bar\theta}^2 =0, \theta\,\bar\theta +
\bar\theta\theta = 0. We impose the (anti-)BRST and (anti-)co-BRST invariant
restrictions on the (anti-)chiral superfields (defined on the (anti-)chiral (2,
1)-dimensional super-submanifolds of the above general (2, 2)-dimensional
supermanifold) to derive the above nilpotent symmetries. We do not exploit the
mathematical strength of the (dual-)horizontality conditions anywhere in our
present investigation. We also discuss the properties of nilpotency, absolute
anticommutativity and (anti-)BRST and (anti-)co-BRST symmetry invariance of the
Lagrangian density within the framework of our augmented (anti-)chiral
superfield formalism. Our observation of the absolute anticommutativity
property is a completely novel result in view of the fact that we have
considered only the (anti-)chiral superfields in our present endeavor.Comment: LaTeX file, 20 pages, journal reference is give
Counterfactual quantum certificate authorization
We present a multi-partite protocol in a counterfactual paradigm. In
counterfactual quantum cryptography, secure information is transmitted between
two spatially separated parties even when there is no physical travel of
particles transferring the information between them. We propose here a
tripartite counterfactual quantum protocol for the task of certificate
authorization. Here a trusted third party, Alice, authenticates an entity Bob
(e.g., a bank) that a client Charlie wishes to securely transact with. The
protocol is counterfactual with respect to either Bob or Charlie. We prove its
security against a general incoherent attack, where Eve attacks single
particles.Comment: 6 pages, 2 figures, close to the published versio
Barrier island erosion and overwash study -- effect of seawalls. Volume 2
This is the second of a pair of reports documenting the effects of storms on beach systems
including the presence of seawalls. With the aim of simulating the effects of overwash on
barrier islands with seawalls and characterizing their response, a series of eight experiments
was conducted at the Coastal Engineering Laboratory of the University of Florida. The barrier
island was simulated by a 400 feet wide horizontal crest and an initially uniform mildly-sloped
(1:19) beach. The effects of positioning the seawall at two different locations as well as the effects
of various storm surge levels and accompanying overtopping were investigated. Experiments
were conducted with both regular and irregular storm waves. With the seawall located at the
slope break between the crest and the sloping beach of the barrier island, and the crest of the
seawall just submerged in sand, the effects on the sediment transport process were found to be
minimal. For the same position of the seawall but with the crest of the seawall raised above the
surrounding ground level, overtopping caused washover of sand indicating substantial transport
in suspension. Increased levels of overtopping tended to accentuate bed profile changes but
supress bar formation (as did irregular waves). Positioning the seawall at the Mean Sea Level
shoreline caused significant scour both immediately landward as well as immediately seaward
of the seawall. A prominent scour trough developed further seaward. The longshore bar was
highly three-dimensional. It appears that seawalls need to be located adequately landward of the
shoreline to discharge their function effectively without adverse effect to the beach. In addition,
concerns for safety warrant the presence of an adequate buffer-zone between the seawall and
the upland property. (61 pp.
Design and Development of Novel Hybrid Precoder for Millimeter-Wave MIMO System
Power consumption and hardware cost reduction with the use of hybrid beamforming in large-scale millimeter wave MIMO systems. The large dimensional analog precoding integrates with the hybrid beamforming based on the phase shifters including digital precoding with lower dimensionality. The reduction of Euclidean distance between the hybrid precoder and fully digital is the major problem to overcome the minimization of resultant spectral efficiency. The issue formulates as a fully digital precoder’s matrix factorization problem based on the analog RF precoder matrix and the digital baseband precoder matrix. An additional element-wise unit modulus constraint is imposed by the phase shifters on the analog RF precoder matrix. The traditional methods have a problem of performance loss in spectral efficiency. In the processing time and iteration, high complexities result in optimization algorithms. In this paper, a novel low complexity algorithm proposes which maximizes the spectral efficiency and reduces the computational processing time.
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