Analytical calculation of the Peierls-Nabarro pinning barrier for one-dimensional parametric double-well models

Lattice effects on the kink families of two models for one-dimensional nonlinear Klein-Gordon systems with double-well on-site potentials are considered. The analytical expression of the generalized Peierls-Nabarro pinning potential is obtained and confronted with numerical simulations.Comment: RevTex, 10 pages, 4 figure

A survey of the choral music of Halsey Stevens

Although Halsey Stevens is a distinguished American composer whose works are widely accepted, and although he has forty-one published works for various choral combinations to his credit, of which four are conceived for combined choral and instrumental forces, there is at present no survey of this choral literature in existence. Since this music receives wide acceptance, the author has felt the need to provide a survey in the hope that the discussions and descriptions will enable choral conductors to discover a source of beautiful music, and to choose works pertinent to their own needs from this body of literature.Chapter I consists of a review of literature pertinent to Stevens and his style.Chapter II is an overview of analysis, including a discussion of analysis in relation to choral music.Chapter III presents a summary of stylistic characteristics as found in Stevens’ choral music. A discussion of the author’s conclusions ends the chapter.The survey is presented in chapters IV and V. Chapter IV deals with the short works. Those which are longer in duration, principally comprising combinations of choral and orchestral forces, constitute chapter V. Campion Suite, for a cappella choir, has been included with this section of longer works, since it is the author’s opinion that it is best performed as an entity.A brief data summary precedes discussion of each work. This summary includes publication information, date of composition, place of composition, any dedicatory information, voicings and instrumentations, sources of text, vocal ranges, and timings. The discussion of the work following the summary is intended to provide a succinct description, sufficient to enable a prospective director to decide whether the work is suitable to his performance needs. Musical examples are included to illustrate various aspects of Stevens’ style as well as to show unusual and interesting features of his music.Appendix I contains the musical examples referred to in the survey, while appendix II lists the published choral music in chronological order.Thesis (D.A.