3,425 research outputs found
On classical q-deformations of integrable sigma-models
JHEP is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0A procedure is developed for constructing deformations of integrable σ-models which are themselves classically integrable. When applied to the principal chiral model on any compact Lie group F, one recovers the Yang-Baxter σ-model introduced a few years ago by C. Klimčík. In the case of the symmetric space σ-model on F/G we obtain a new one-parameter family of integrable σ-models. The actions of these models correspond to a deformation of the target space geometry and include a torsion term. An interesting feature of the construction is the q-deformation of the symmetry corresponding to left multiplication in the original models, which becomes replaced by a classical q-deformed Poisson-Hopf algebra. Another noteworthy aspect of the deformation in the coset σ-model case is that it interpolates between a compact and a non-compact symmetric space. This is exemplified in the case of the SU(2)/U(1) coset σ-model which interpolates all the way to the SU(1, 1)/U(1) coset σ-modelPeer reviewedFinal Published versio
On the classical equivalence of monodromy matrices in squashed sigma model
We proceed to study the hybrid integrable structure in two-dimensional
non-linear sigma models with target space three-dimensional squashed spheres. A
quantum affine algebra and a pair of Yangian algebras are realized in the sigma
models and, according to them, there are two descriptions to describe the
classical dynamics 1) the trigonometric description and 2) the rational
description, respectively. For every description, a Lax pair is constructed and
the associated monodromy matrix is also constructed. In this paper we show the
gauge-equivalence of the monodromy matrices in the trigonometric and rational
description under a certain relation between spectral parameters and the
rescalings of sl(2) generators.Comment: 32pages, 3figures, references added, introduction and discussion
sections revise
Lunin-Maldacena backgrounds from the classical Yang-Baxter equation -- Towards the gravity/CYBE correspondence
We consider \gamma-deformations of the AdS_5xS^5 superstring as Yang-Baxter
sigma models with classical r-matrices satisfying the classical Yang-Baxter
equation (CYBE). An essential point is that the classical r-matrices are
composed of Cartan generators only and then generate abelian twists. We present
examples of the r-matrices that lead to real \gamma-deformations of the
AdS_5xS^5 superstring. Finally we discuss a possible classification of
integrable deformations and the corresponding gravity solution in terms of
solutions of CYBE. This classification may be called the gravity/CYBE
correspondence.Comment: 18 pages, no figure, LaTeX, v2:references and further clarifications
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The classical origin of quantum affine algebra in squashed sigma models
We consider a quantum affine algebra realized in two-dimensional non-linear
sigma models with target space three-dimensional squashed sphere. Its affine
generators are explicitly constructed and the Poisson brackets are computed.
The defining relations of quantum affine algebra in the sense of the Drinfeld
first realization are satisfied at classical level. The relation to the
Drinfeld second realization is also discussed including higher conserved
charges. Finally we comment on a semiclassical limit of quantum affine algebra
at quantum level.Comment: 25 pages, 2 figure
Exploring Learning Problems of Filipino Nurse Candidates Working in Japan: Based on the Results of a Practice National Board Examination of Japan Given in English
This article investigates the status of the education and training of Filipino nurse candidates who have been working in Japan under the Japan-Philippine Economic Partnership Agreement (JPEPA). A survey was conducted among Filipino nurse candidates, using a practice examination based on the English version of Japan’s National Board Examination for Registered Nurses in 2009. Categorized by area, the mean correct answer rate for nursing-related questions ranged between 61% and 73%; the rate for questions concerning basic knowledge of body functions and diseases ranged between 55% and 57%. There was a large gap in terms of the results of the examination between those who had previously seen the exam questions and those who had never seen them. While 57.1% of those who had previously seen the questions satisfied the acceptance criteria, only 23.7%of those who had never viewed the test satisfied it. Based on these results, the factors which serve as obstacles that Filipino nurse candidates encounter in passing the national examination include not only difficulties in acquiring Japanese proficiency but also differences between Japan and the Philippines in respect to the nursing education curriculum and basic nursing policies
Hybrid classical integrable structure of squashed sigma models -- a short summary
We give a short summary of our recent works on the classical integrable
structure of two-dimensional non-linear sigma models defined on squashed
three-dimensional spheres. There are two descriptions to describe the classical
dynamics, 1) the rational description and 2) the trigonometric description. It
is possible to construct two different types of Lax pairs depending on the
descriptions, and the classical integrability is shown by computing classical
r/s-matrices satisfying the extended Yang-Baxter equation in both descriptions.
In the former the system is described as an integrable system of rational type.
On the other hand, in the latter it is described as trigonometric type. There
exists a non-local map between the two descriptions and those are equivalent.
This is a non-local generalization of the left-right duality in principal
chiral models.Comment: 10 pages, Proceedings of QTS7, Prague, Czech Republic, 201
Exploring Learning Problems of Filipino Nurse Candidates Working in Japan: Based on the Results of a Practice National Board Examination of Japan Given in English
This article investigates the status of the education and training of Filipino nurse candidates who have been working in Japan under the Japan-Philippine Economic Partnership Agreement (JPEPA). A survey was conducted among Filipino nurse candidates, using a practice examination based on the English version of Japan’s National Board Examination for Registered Nurses in 2009. Categorized by area, the mean correct answer rate for nursing-related questions ranged between 61% and 73%; the rate for questions concerning basic knowledge of body functions and diseases ranged between 55% and 57%. There was a large gap in terms of the results of the examination between those who had previously seen the exam questions and those who had never seen them. While 57.1% of those who had previously seen the questions satisfied the acceptance criteria, only 23.7%of those who had never viewed the test satisfied it. Based on these results, the factors which serve as obstacles that Filipino nurse candidates encounter in passing the national examination include not only difficulties in acquiring Japanese proficiency but also differences between Japan and the Philippines in respect to the nursing education curriculum and basic nursing policies
Feasibility study of an Integrated Program for Aerospace vehicle Design (IPAD). Volume 4: IPAD system design
The computing system design of IPAD is described and the requirements which form the basis for the system design are discussed. The system is presented in terms of a functional design description and technical design specifications. The functional design specifications give the detailed description of the system design using top-down structured programming methodology. Human behavioral characteristics, which specify the system design at the user interface, security considerations, and standards for system design, implementation, and maintenance are also part of the technical design specifications. Detailed specifications of the two most common computing system types in use by the major aerospace companies which could support the IPAD system design are presented. The report of a study to investigate migration of IPAD software between the two candidate 3rd generation host computing systems and from these systems to a 4th generation system is included
First evidence for spectral state transitions in the ESO243-49 hyper luminous X-ray source HLX-1
The brightest Ultra-Luminous X-ray source (ULX), ESO 243-49 HLX-1, with a 0.2
- 10 keV X-ray luminosity of up to 10^42 erg s^-1, provides the strongest
evidence to date for the existence of intermediate mass black holes. Although
small scale X-ray spectral variability has already been demonstrated, we have
initiated a monitoring campaign with the X-ray Telescope onboard the Swift
satellite to search for luminosity-related spectral changes and to compare its
behavior with the better studied stellar mass black holes. In this paper, we
report a drop in the XRT count rate by a factor of ~8 which occurred
simultaneously with a hardening of the X-ray spectrum. A second observation
found that the source had re-brightened by a factor of ~21 which occurred
simultaneously with a softening of the X-ray spectrum. This may be the first
evidence for a transition between the low/hard and high/soft states.Comment: Accepted by ApJ Letter, 2 figure
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