Quantum Potential and Symmetries in Extended Phase Space

The behavior of the quantum potential is studied for a particle in a linear and a harmonic potential by means of an extended phase space technique. This is done by obtaining an expression for the quantum potential in momentum space representation followed by the generalization of this concept to extended phase space. It is shown that there exists an extended canonical transformation that removes the expression for the quantum potential in the dynamical equation. The situation, mathematically, is similar to disappearance of the centrifugal potential in going from the spherical to the Cartesian coordinates that changes the physical potential to an effective one. The representation where the quantum potential disappears and the modified Hamilton-Jacobi equation reduces to the familiar classical form, is one in which the dynamical equation turns out to be the Wigner equation.Comment: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA

Operator Gauge Symmetry in QED

In this paper, operator gauge transformation, first introduced by Kobe, is applied to Maxwell's equations and continuity equation in QED. The gauge invariance is satisfied after quantization of electromagnetic fields. Inherent nonlinearity in Maxwell's equations is obtained as a direct result due to the nonlinearity of the operator gauge transformations. The operator gauge invariant Maxwell's equations and corresponding charge conservation are obtained by defining the generalized derivatives of the first and second kinds. Conservation laws for the real and virtual charges are obtained too. The additional terms in the field strength tensor are interpreted as electric and magnetic polarization of the vacuum.Comment: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA

An empirical study to determine the critical success factors on customer retention: A case study of Iranian banking sector

One of the most important strategic issues for any enterprise is to create and deliver superior value for its customers and provide enough evidences to convince them not to choose another competitive. In this study, we study the effects of customer value, customer satisfaction and customer loyalty on customer retention. The results indicate that all aspects of the customer value have positive relationships with customer satisfaction but only emotional value has a positive and direct relationship with customer loyalty. The study confirms that while none of customer value aspects has direct and positive relationship with customer retention, both customer satisfaction and customer loyalty positively and directly affect customer retention

The application of water cycle algorithm to portfolio selection

Portfolio selection is one of the most vital financial problems in literature. The studied problem is a nonlinear multi-objective problem which has been solved by a variety of heuristic and metaheuristic techniques. In this article, a metaheuristic optimiser, the multiobjective water cycle algorithm (MOWCA), is represented to find efficient frontiers associated with the standard mean-variance (MV) portfolio optimisation model. The inspired concept of WCA is based on the simulation of water cycle process in the nature. Computational results are obtained for analyses of daily data for the period January 2012 to December 2014, including S&P100 in the US, Hang Seng in Hong Kong, FTSE100 in the UK, and DAX100 in Germany. The performance of the MOWCA for solving portfolio optimisation problems has been evaluated in comparison with other multi-objective optimisers including the NSGA-II and multiobjective particle swarm optimisation (MOPSO). Four well-known performance metrics are used to compare the reported optimisers. Statistical optimisation results indicate that the applied MOWCA is an efficient and practical optimiser compared with the other methods for handling portfolio optimisation problems

A first case of tinea imbricata from Iran

Tinea imbricata is an uncommon dermatophytosis caused by the anthropophilic dermatophyte Trichophyton concentricum in endemic regions. In the present study, a 10- year-old girl was examined for tinea imbricata. Microscopic examination revealed the presence of hyaline, septate, branching hyphae and its cultures on Sabouraud dextrose agar yielded T. concentricum. The patient responded to treatment with oral terbinafine 250mg/day topical clotrimazole (1% ointment), topical miconazole (2% cream) two times daily and potassium permanganate for daily washing for four weeks. In the present study, we reported the first case of tinea imbricate from Iran

Analysis of Task-Based Language Teaching (TBLT) In the process of teaching and learning the phonetic system of the Arabic language

One of the main challenges in teaching Arabic language is teaching the phonetic system in a systematic method Because language learners need to understand different phonetic levels through practical training in order to establish communicate purposefully and interact properly with native speakers, so that in addition to acceptable and comprehensible pronunciation in their interactions, they can provide correct verbal and non-verbal reactions to the spoken word. Therefore, the present study intends to study the task-based approach in teaching the Arabic sounds with a descriptive-comparative method. The results indicate that main difference between Persian sounds and Arabic is in the fourth level of difficulty (θ /ħ /ð /sˤ /dˤ /tˤ /ðˤ /ʕ /ɣ) and then in the third level (z /s /ʃ /dʒ /k /q /w). the task-based approach with the “pre-task phase” makes the learner cognitively aware of these differences as well as the level of Suprasegmental and creates the necessary preparations, then in the stage During task with emphasis on all aspects of language at the level of Segmental and suprasegmental of speech and behaviorally reinforce them by engaging the learner in applied tasks based on their needs in communication situations, emphasizing pivotal interaction. So that by using real tasks and in the context of the audio text, in addition to placing the learner in areal communication situation, the challenge of changing the properties of sounds, is solved by accompaniment, and by stabilizing the cognitive dimension and repetition of tasks in quasi-real situations in the post-task phase. In creases the communication ability of language learners. Therefore, it can be said that the task-based approach is quite suitable for use in teaching the phonetic system of the Arabic language