7,436 research outputs found

    Phonon Thermodynamics versus Electron-Phonon Models

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    Applying the path integral formalism we study the equilibrium thermodynamics of the phonon field both in the Holstein and in the Su-Schrieffer-Heeger models. The anharmonic cumulant series, dependent on the peculiar source currents of the {\it e-ph} models, have been computed versus temperature in the case of a low energy oscillator. The cutoff in the series expansion has been determined, in the low TT limit, using the constraint of the third law of thermodynamics. In the Holstein model, the free energy derivatives do not show any contribution ascribable to {\it e-ph} anharmonic effect. We find signatures of large {\it e-ph} anharmonicities in the Su-Schrieffer-Heeger model mainly visible in the temperature dependent peak displayed by the phonon heat capacity

    The Government of London and its relations with the Crown 1400 - 1450

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    PhDThe available sources have, to some extent, determined the form of this thesis, which was undertaken in the hope that a more detailed study of the relations between London and the Crown during the years 1400-1150 would place in perspective the crises with which it begins and ends. The most important source of material for this study has been the Journals of the Court of Aldermen and Common Council which survive from 1416 (the years 1429- 1436 are missing). Historians with the help of a nineteenth century index have quarried in these Journals, but they have never been read through systematically. Journals nos. 3 and 6, having been wrongly bound up, could not be used until their pages had been sorted into the correct order from the internal evidence of their contents. The scribes who compiled the Journals were both careless and cautious which increases the difficulty in interpreting their crabbed notes. From studying the Journals dominant themes emerged which were then followed up at the Public Record Office and elsewhere. The conclusions from this study fall into three main categories. The Journals provided a great deal of material from which it was possible to draw a much more detailed picture of the machinery and business of the government of medieval London. The Aldermen and civic officials emerge as conservative, but conscientious, men who might press hardly upon minority interests, but had constantly before their eyes the needs of the City as a whole. Secondly it has been possible to tidy up the chronology of the crises themselves. At such times as Bolingbroke's usurpation and Cade's revolt the civic scribes were least active and most cautious. But it seems clear that the London support for both these men has been exaggerated and that the fundamental conservatism of the City governors was not easily rocked, whether by royal scions or Kentish peasants. But this study has proved most useful where the more mundane contact between the Crown and the citizens could be examined, In this way it has been possible to place the financial relations between the King and the City in perspective, and to realize that the King did not come as a beggar to the Londoners, since he had at his disposal all the chartered freedoms and privileges which were essential to the communal and economic life of the City. London, in spite of its great prestige and financial importance, still operated in the fifteenth century within a framework of royal privilege. 'While the memory of Richard II's action in 1392 was still, green, the Londoners were in no position to demand redress of grievances before supply. In understanding the delicate balance of the relationship between the Crown and the Londoners it is easier to understand the survival of the Lancastrian dynasty

    Student progress monitoring: teachers\u27 perceptions

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    The Mississippi Student Progress Monitoring System (MSPMS) was developed for the Mississippi Department of Education to be used to monitor student progress on the state framework which constitutes the curriculum for each course taught in Mississippi schools. This study was designed to investigate teachers’ perceptions of the implementation and use of the MSPMS. Research question 1 was to determine if the various independent variables of age, level of education, years of experience as an educator, level of school where teaching, perceived level of computer and/or technology comfort, perceived level of computer and/or technology experience, subject area taught, number of MSPMS tests created, number of MSPMS tests given, amount of support provided, whether program works, and importance of information gained from MSPMS made any difference in teachers’ perceptions of the implementation and use of the MSPMS; and research question 2 was to determine whether the teachers’ perceptions and the various independent variables had any significant relationships. Research question 3 looked at teachers’ attitudes toward MSPMS. There were no statistically significant differences among the dependent and independent variables. Findings for research question 2 showed that there were no statistically significant correlations among the dependent and independent variables. However, correlations among the independent variables revealed statistically significant relationships between age and years of experience, subjects taught and school level taught, technology experience and level of education, and subjects taught and number of tests given. Examination of the response frequencies for situations in the vignettes for research question 3 revealed that teachers reported feeling more frustrated than anything else when confronted with adversities with the technologies or the MSPMS. All of the findings in this study are limited to a rural Mississippi school district using MSPMS

    Establishing Criteria for the Pre-Service Selection of Teachers with Special Application to the Utah State Agricultural College

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    Our American culture and civilization depends in large measure upon the recruiting of the right kind of men and women to be teachers in our American schools and colleges. All professions depend on effective teaching for their life blood. Many educators and colleges during the past few years have become concerned with pre-service selection methods for improving the teaching personnel. This concern has become somewhat intensified at the present time, largely as a result of four factors. One factor is the large number of returning servicemen, who are turning to teaching as a career. A second factor is improved salaries and tenure laws. A third factor, suggested by Dr. Ray C. Maul is that many people are turning to teaching only because schools continue to operate though good times and bad. A fourth factor common to many prospective teachers is that the idealism connected with teaching attracts them into the profession. The objective of this study is to obtain evidence from a reveiw of literature, opinions of educators and the preservice selection practices used in other colleges to establish criteria that are considered to be the most desirable factors and techniques used in the pre-service selection of teachers as found by an investigation of the literature. The criteria will be used as a basis for making an analysis of the available records of the students and practices used in the guidance program in the School of Education at Utah State Agricultural College. In this manner the limitations or success of the guidance program as indicated will be somewhat more meaningful

    Heat capacity and thermal expansion at low temperatures

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