Fermionic R-operator approach for the small-polaron model with open boundary condition

Exact integrability and algebraic Bethe ansatz of the small-polaron model with the open boundary condition are discussed in the framework of the quantum inverse scattering method (QISM). We employ a new approach where the fermionic R-operator which consists of fermion operators is a key object. It satisfies the Yang-Baxter equation and the reflection equation with its corresponding K-operator. Two kinds of 'super-transposition' for the fermion operators are defined and the dual reflection equation is obtained. These equations prove the integrability and the Bethe ansatz equation which agrees with the one obtained from the graded Yang-Baxter equation and the graded reflection equations.Comment: 10 page

Formación en psicología para entrenadores de fútbol : una propuesta metodológica

En este trabajo se presenta una metodología específica para la formación en psicología de entrenadores de fútbol. Se propone la utilización de técnicas de la dinámica de grupos, agrupando a los entrenadores por grupos homogéneos, utilizando como criterio fundamental la pertenencia de éstos a un mismo club deportivo. Se presentan algunas de las técnicas utilizadas (torbellino de ideas, trabajo individual, trabajos en pequenos grupos, exposiciones y debates, etc.), sí como los contenidos de las sesiones formativas: variables psicológicas implicadas en el rendimiento deportivo de los futbolistas (en entrenamiento y competición) y variables psicológicas del entrenador para optimizar su competencia profesional. Finalmente, se presenta la valoración realizada por los entrenadores respecto a la sesiones formativas.This work presents a specific methodology to form football coaches in psychology. It's proposed the use of techniques of group dynamics, gathering the coaches into «homogeneous groups», considering as an essential criterion they belong to the same sport club. Some of the used techniques are presented (brainstorming, individual work, small groups work, expositions and discussions, etc.), as well as the contents of the formative sessions: psychological variables of football players influencing in sport performance (in training and competition) and psychological variables of the coach to improve his professional competence. Finally, it's presented the valuation done by the coaches respected to the formative sessions

Fermionic R-Operator and Integrability of the One-Dimensional Hubbard Model

We propose a new type of the Yang-Baxter equation (YBE) and the decorated Yang-Baxter equation (DYBE). Those relations for the fermionic R-operator were introduced recently as a tool to treat the integrability of the fermion models. Using the YBE and the DYBE for the XX fermion model, we construct the fermionic R-operator for the one-dimensional (1D) Hubbard model. It gives another proof of the integrability of the 1D Hubbard model. Furthermore a new approach to the SO(4) symmetry of the 1D Hubbard model is discussed.Comment: 25 page

Negotiating Trust on the Grid

Grids support dynamically evolving collections of resources and users, usually spanning multiple administrative domains. The dynamic and crossorganizational aspects of Grids introduce challenging management and policy issues for controlling access to Grid resources. In this paper we show how to extend the Grid Security Infrastructure to provide better support for the dynamic and cross-organizational aspects of Grid activities, by adding facilities for dynamic establishment of trust between parties. We present the PeerTrust language for access control policies, which is based on guarded distributed logic programs, and show how to use PeerTrust to model common Grid trust needs

Jordan-Wigner fermionization for the one-dimensional Bariev model of three coupled XY chains

The Jordan-Wigner fermionization for the one-dimensional Bariev model of three coupled XY chains is formulated. The Lax operator in terms of fermion operators and the quantum R-matrix are presented explicitly. Furthermore, the graded reflection equations and their solutions are discussed.Comment: 10 pages, no figur

Fermionisation of the Spin-S Uimin-Lai-Sutherland Model: Generalisation of Supersymmetric t-J Model to Spin-S

The spin-1 Uimin-Lai-Sutherland (ULS) isotropic chain model is expressed in terms of fermions and the equivalence of the fermionic representation to the supersymmetric t-J model is established directly at the level of Hamiltonians.The spin-S ULS model is fermionized and the Hamiltonian of the corresponding generalisation of the t-J model is written down.Comment: 16 page

The Pudding of Trust

Trust - "reliance on the integrity, ability, or character of a person or thing" - is pervasive in social systems. We constantly apply it in interactions between people, organizations, animals, and even artifacts. We use it instinctively and implicitly in closed and static systems, or consciously and explicitly in open or dynamic systems. An epitome for the former case is a small village, where everybody knows everybody, and the villagers instinctively use their knowledge or stereotypes to trust or distrust their neighbors. A big city exemplifies the latter case, where people use explicit rules of behavior in diverse trust relationships. We already use trust in computing systems extensively, although usually subconsciously. The challenge for exploiting trust in computing lies in extending the use of trust-based solutions, first to artificial entities such as software agents or subsystems, then to human users' subconscious choices

On the Classical W4(2)W_{4}^{(2)} Algebra

We consider the classical \w42 algebra from the integrable system viewpoint. The integrable evolution equations associated with the \w42 algebra are constructed and the Miura maps , consequently modifications, are presented. Modifying the Miura maps, we give a free field realization the classical \w42 algebra. We also construct the Toda type integrable systems for it.Comment: 14 pages, latex, no figure