892 resultados para write-down
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This is the second in a series of articles whose ultimate goal is the evaluation of the matrix elements (MEs) of the U(2n) generators in a multishell spin-orbit basis. This extends the existing unitary group approach to spin-dependent configuration interaction (CI) and many-body perturbation theory calculations on molecules to systems where there is a natural partitioning of the electronic orbital space. As a necessary preliminary to obtaining the U(2n) generator MEs in a multishell spin-orbit basis, we must obtain a complete set of adjoint coupling coefficients for the two-shell composite Gelfand-Paldus basis. The zero-shift coefficients were obtained in the first article of the series. in this article, we evaluate the nonzero shift adjoint coupling coefficients for the two-shell composite Gelfand-Paldus basis. We then demonstrate that the one-shell versions of these coefficients may be obtained by taking the Gelfand-Tsetlin limit of the two-shell formulas. These coefficients,together with the zero-shift types, then enable us to write down formulas for the U(2n) generator matrix elements in a two-shell spin-orbit basis. Ultimately, the results of the series may be used to determine the many-electron density matrices for a partitioned system. (C) 1998 John Wiley & Sons, Inc.
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We consider two different kinds of fluctuations in an ion trap potential: external fluctuating electrical fields, which cause statistical movement (wobbling) of the ion relative to the center of the trap, and fluctuations of the spring constant, which an due to fluctuations of the ac component of the potential applied in the Paul trap for ions. We write down master equations for both cases and, averaging out the noise, obtain expressions for the heating of the ion. We compare our results to previous results for far-off resonance optical traps and heating in ion traps. The effect of fluctuating external electrical fields for a quantum gate operation (controlled-NOT) is determined and the fidelity for that operation derived. [S1050-2947(99)06005-9].
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We write down the renormalization-group equations for the Yukawa-coupling matrices in a general multi-Higgs-doublet model. We then assume that the matrices of the Yukawa couplings of the various Higgs doublets to right-handed fermions of fixed quantum numbers are all proportional to each other. We demonstrate that, in the case of the two-Higgs-doublet model, this proportionality is preserved by the renormalization-group running only in the cases of the standard type-I, II, X, and Y models. We furthermore show that a similar result holds even when there are more than two Higgs doublets: the Yukawa-coupling matrices to fermions of a given electric charge remain proportional under the renormalization-group running if and only if there is a basis for the Higgs doublets in which all the fermions of a given electric charge couple to only one Higgs doublet.
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Jornadas de Contabilidade e Fiscalidade promovidas pelo Instituto Superior de Contabilidade e Administração do Porto, em Abril de 2009
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Aquest projecte és fruit de la meva necessitat de buscar amb el meu instrument, la percussió, i més concretament amb la pandereta, recursos tècnics i interpretatius per abordar la interpretació de la música antiga. Com a punt de partida he analitzat iconografia i algunes fonts literàries per tal d’entendre i poder explicar que s’entén quan parlem de la percussió històrica. Posteriorment s’observen algunes pràctiques encara existents en les tradicions musicals italianes i àrabs i com aquestes poden ser el punt de partida per a configurar una maner pròpia i moderna d’ interpretar i anotar la música històrica.
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Yritysten toimintaympäristössä on tapahtunut viime vuosina suuria muutoksia ja niitä tapahtuu tulevaisuudessakin yhä nopeammassa tahdissa. Yritysten on kehitettävä suorituskykyään, jotta sidosryhmien tarpeet kyetään tyydyttämään. Suorituskyvyn kehittäminen perustuu mittaustuloksiin ja niistä tehtäviin johtopäätöksiin. Hävikin mittaaminen ja analysointi on osa yrityksen suorituskykyä. Mittarit, joita käytetään suorituskyvyn mittaamiseen, tulee olla luotettavia. Mittaustuloksia tulee pystyä hyödyntämään tehokkaasti. Makeisteollisuudessa hävikkimärät ovat jatkuvasti kasvaneet. Tämä oli heräte tälle tutkimukselle yrittää löytää paras tapa mitata hävikkiä. Toinen tavoite oli selvittää, kuinka olisi mahdollista vähentää hävikin syntymistä. Näiden tavoitteiden saavuttaminen vaati selvitystä, kuinka hävikkiä mitataan tänä päivänä, mistä hävikki syntyy ja kuinka siihen reagoidaan. Tutkimuksessa mukana olevassa yrityksessä on laaja valikoima erilaisia makeistuotteita, sokerimakeisia ja suklaatuotteita. Tähän tutkimukseen valittiin saman tyyppiset valmistuslinjat jokaiselta tehtaalta. Näiltä linjoilta valittiin tutkittavaksi kaksi erilaista tuotetta. Tämän tutkimuksen tulos oli, että hävikkiä käsitellään jamitataan hyvin eri tavalla jokaisella tehtaalla. Hävikkiä mitataan juuri, kutenkirjallisuudessa on mainittu verraten myyntiin tai valmistettuihin kiloihin. Näin ollen ei ollut tarvetta muuttaa mittausmenetelmää, joka oli tutkimuksen päätavoite. Tärkeintä oli löytää kohdat, joissa hävikkiä syntyy. Ajan puutteen vuoksiei ollut mahdollista selvittää kaikkia hävikin syntyyn vaikuttavia syitä tai paikkoja, joissa hävikkiä syntyy. Suurin syy hävikkiin on huono laatu. Tähän syynäon osaamisen ja koulutuksen puute. Syynä hävikin syntyyn voi olla myös raaka-aineissa tai resepteissä. Tässä tutkimuksessa käytettiin Bill Crosbyn kirjaa 'Laatu on ilmaista'. Kirjassa käsitellään -14 kohdan ohjelmaa', joka voisi olla hyvä ohjelma nostaa tuotteiden laatutasoa myös tutkimuksessa mukana olevassa yrityksessä.On tärkeää tarkentaa säännöt, kuinka kirjataan hävikkiä, tarkistaa reseptit ja koulutuksen avulla nostaa osaamisen tasoa. Tällaiselle projektille täytyy olla koko organisaation ja ylimmän johdon tuki. Kaikki ne miljoonat eurot, jotka heitetään pois, voisivat olla tuloksessa. Se ei tapahdu yhdessä yössä, vaan vaatiijatkuvaa työtä tavoitteen saavuttamiseen.
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The birth of a preterm infant is in most cases unexpected and can be a distressing experience for parents. Parents of premature babies report more stress, experience more adjustment difficulties and need for support during the first year after delivery compared to parents of infants born at term. It has been documented that parents may experience posttraumatic stress reactions, anxiety and depression following the premature birth of their baby, which subsequently may impact on the mother-baby-interactions, their attachment relationship and the cognitive, social and behavioural development of the baby. In this pilot study, we offered an expressive writing intervention to women who recently had a premature baby to alleviate their psychological distress and to improve their physical health. During the expressive writing intervention, women were asked to write down their deepest thoughts and feelings about the most traumatic aspect of their experience of having a premature baby for 15 min over three consecutive days. The aims of the study were as follows: (1) To evaluate the effect of expressive writing on psychological and physical health in women who recently had a premature baby. (2) To evaluate the effect of expressive writing on the use of healthcare services and medication in this population. (3) To evaluate the acceptability and feasibility of this intervention for this population. Forty participants were randomly allocated to either the expressive writing intervention group or a wait list control group. Pre- and post questionnaires to evaluate the effectiveness of the expressive writing intervention, as well as their acceptability and feasibility were completed. The intervention took place when the baby was 3 months of corrected age. Post-measures were completed at 1 and 3 months following the intervention. Results and their clinical implications will be discussed with regards to the implementation of this safe and cost-effective method as a preventative measure in the routine care of women who recently gave birth to a premature baby
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Cette étude traite du droit de grève et de sa protection en milieu de travail et en milieu étudiant au Québec. À la suite de l’importante et mémorable grève générale étudiante du printemps 2012, encore appelée printemps érable et des répercussions qu’elle a engendrées, il était important de consigner par écrit une analyse du droit de grève et de la protection dont ce droit bénéficie, non seulement au niveau des relations de travail mais aussi en milieu étudiant. Cette étude propose ainsi une rétrospective sur l’organisation à l’origine de son existence, c'est-à-dire le syndicat. Elle porte un regard particulier sur le syndicalisme ouvrier et le syndicalisme étudiant. Pour une bonne compréhension de ces deux catégories d’associations, nous rappellerons l’histoire de chacune d’elle avant de porter une attention particulière au droit de grève dont elles jouissent ainsi qu’à l’encadrement juridique de ce dernier. Pour finir, nous analyserons les fondements constitutionnels possibles de la grève en tant que moyen collectif d’expression et d’action des associations de salariés et d’étudiants. Nous soulignons que cette étude est basée sur divers ouvrages portant sur le syndicalisme ouvrier et étudiant ainsi que sur le droit de grève et sa protection, thèmes traités par d’éminents professeurs et juristes, qui ont été notre source d’inspiration.
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Este es un estudio de investigación cualitativo, exploratorio, con metodología de estudio de caso en el que se indaga sobre las características y la dinámica del poder manifiesta en la relación de una pareja en separación y que se somete a un proceso de mediación desde un modelo relacional simbólico.Estos aspectos se determinaron a partir de la observación que se realizó a la pareja durante el proceso de mediación, por medio de registros audio-visuales, el desarrollo del genograma familiar y las entrevistas a profundidad durante el proceso; se obtuvieron los siguientes resultados de los enunciados verbales y de las expresiones gestuales del hombre y de la mujer: El aspecto de poder que se presenta en la pareja con mayor énfasis tiene relación con los hijos, el hombre retiene físicamente a los hijos lo que le otorga un manejo de poder en torno a ella y la mujer se aleja de ellos para evitar confrontaciones con su ex compañero. Un segundo aspecto de poder que se manifiesta tanto en el hombre como en la mujer es el relacionado con los rasgos personales, se identifica un carácter manipulador. En él se evidencia por el manejo inadecuado de la relación de los hijos con la madre y en ella se hace visible a través de la invención de situaciones o mentiras para justificar sus vacíos. En la dinámica de poder evidenciada en la pareja objeto de esta investigación el poder se manifiesta en todo argumento defensivo, en las justificaciones, recriminaciones, en la percepción, en la desconfianza y el imaginario negativo que se tiene del otro, tornándose así en un poder preconcebido como absoluto y despótico por parte de los dos miembros de la pareja, estos aspectos de poder identificados se constituyen en verdaderos obstáculos para el negociar de la pareja, limitando la posibilidad de intercambio y entendimiento necesarios para la culminación de la mediación. Es de anotar que el presente proyecto presenta la clasificación de riesgo mínimo, según la Resolución 8430 de 1993.
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En el marc del model transteòric de canvi (Prochaska, DiClemente i Norcross, 1992) i del model de l'autocontrol (Rachlin, 1989), s'examinen les característiques de la conducta de fumar així com la percepció de la magnitud i la demora de les conseqüències positives i negatives d'aquest consum, a fi de conèixer la seva relació amb l'etapa de canvi en la cessació tabàquica. Amb aquest objectiu s'entrevista a una mostra representativa de 281 membres (54,8% homes i 45,2% dones; mitjana d'edat = 37,26 anys, DT = 8,77; 48,8% no fumadors, 27,4% fumadors i 23,8% exfumadors) del personal acadèmic i d'administració i serveis de la Universitat de Girona. Els resultats mostren que més de la meitat dels fumadors es troben a l'etapa de Precontemplació (sense intenció ferma d'abandonar el consum de tabac en els propers 6 mesos) i la majoria d'exfumadors se situen a l'etapa de Manteniment (mínim de sis mesos sense fumar). També s'observen diferències en algunes de les variables examinades segons l'etapa de canvi de manera que els fumadors en Contemplació-Preparació (amb intenció ferma d'abandonar el consum de tabac en els propers 6 mesos) presenten un elevat índex de perjudicis percebuts, informen d'haver rebut més consell mèdic i realitzen amb major freqüència inhalacions a cada cigarreta. En canvi, els fumadors en Precontemplació són els qui més responen consumir tabac baix en nicotina mentre que els exfumadors en Acció o Manteniment són els qui més tendeixen a relacionar de manera immediata fumar i les seves conseqüències negatives a curt i mitjà termini, i els qui presenten major puntuació en l'índex de beneficis percebuts. Aquestes dades corroboren la importància de les intervencions clíniques específiques en les diferents etapes de l'abandonament del consum de tabac, suggereixen que les campanyes preventives s'haurien de focalitzar preferentment en les conseqüències negatives immediates de fumar i apunten a la conveniència de tenir en compte la notable valoració positiva dels beneficis de fumar per part dels exfumadors en els programes de prevenció de recaigudes. Així mateix, la constatació del poder explicatiu de la variable demora en la diferenciació dels subjectes en funció de l'etapa de canvi, planteja la conveniència d'incloure aquesta variable en les avaluacions dels pros i contres de fumar a fi de conèixer amb major precisió els seus pesos relatius.
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It is now-a-days more and more common in the academic world to use new forms of “learning-tools”. One of those is the “reflection protocol”, which usually consist of a few pages of freely written text, related to something the students have read. There seems to be a lot of different opinions about the value to use this method. Some teachers and students are enthusiastic and others are rather critical. To write a “reflection protocol” is not in the first place to do a summery, a review, not even to analyze a text. Instead it is about to write down thoughts and questions that comes up as a result of the reading. It is also about doing associations, reflections and to interpret a text and relate this to a theme of some kind. The purpose to use “reflection protocols” is, as we see it, mainly for the student to practice independent thinking from a scientific point of view, but it also gives a possibility to a better understanding of another person’s thinking. This seems to open up for a fruitful dialogue and a way to learn. We will in this paper discuss if that could be the case.
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The aim of the present work is to contribute to the teaching-learning process in Mathematics through an alternative which tries to motivate the student so that he/she will learn the basic concepts of Complex Numbers and realize that they are not pointless. Therefore, this work s general objective is to construct a didactic sequence which contains structured activities that intends to build up, in each student s thought, the concept of Complex Numbers. The didactic sequence is initially based on a review of the main historical aspects which begot the construction of those numbers. Based on these aspects, and the theories of Richard Skemp, was elaborated a sequence of structured activities linked with Maths history, having the solution of quadratic equations as a main starting point. This should make learning more accessible, because this concept permeates the students previous work and, thus, they should be more familiar with it. The methodological intervention began with the application of that sequence of activities with grade students in public schools who did not yet know the concept of Complex Numbers. It was performed in three phases: a draft study, a draft study II and the final study. Each phase was applied in a different institution, where the classes were randomly divided into groups and each group would discuss and write down the concepts they had developed about Complex Numbers. We also use of another instrument of analysis which consisted of a recorded interview of a semi-structured type, trying to find out the ways the students thought in order to construct their own concepts, i.e. the solutions of the previous activity. Their ideas about Complex Numbers were categorized according to their similarities and then analyzed. The results of the analysis show that the concepts constructed by the students were pertinent and that they complemented each other this supports the conclusion that the use of structured activities is an efficient alternative for the teaching of mathematics
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We show that in SU(3)(C) circle times SU(3)(L) circle times U(1)(N) (3-3-1) models embedded with a singlet scalar playing the role of the axion, after imposing scale invariance, the breaking of Peccei-Quinn symmetry occurs through the one-loop effective potential for the singlet field. We, then, analyze the structure of spontaneous symmetry breaking by studying the new scalar potential for the model, and verify that electroweak symmetry breaking is tightly connected to the 3-3-1 breaking by the strong constraints among their vacuum expectation values. This offers a valuable guide to write down the correct pattern of symmetry breaking for multi-scalar theories. We also obtained that the accompanying massive pseudo-scalar, instead of acquiring mass of order of Peccei-Quinn scale as we would expect, develops a mass at a much lower scale, a consequence solely of the breaking via Coleman-Weinberg mechanism. (c) 2005 Published by Elsevier B.V.
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The scope and aim of this work is to describe the two-body interaction mediated by a particle (either the scalar or the gauge boson) within the light-front formulation. To do this, first of all we point out the importance of propagators and Green functions in Quantum Mechanics. Then we project the covariant quantum propagator onto the light front time to get the propagator for scalar particles in these coordinates. This operator propagates the wave function from x(+) = 0 to x(+) > 0. It corresponds to the definition of the time ordering operation in the light front time x(+). We calculate the light-front Green's function for 2 interacting bosons propagating forward in x(+). We also show how to write down the light front Green's function from the Feynman propagator and finally make a generalization to N bosons.