2,477 research outputs found
The Gas Temperature of Starless Cores in Perseus
In this paper we study the determinants of starless core temperatures in the
Perseus molecular cloud. We use NH3 (1,1) and (2,2) observations to derive core
temperatures (T_kin) and data from the COMPLETE Survey of Star Forming Regions
and the c2d Spitzer Legacy Survey for observations of the other core and
molecular cloud properties. The kinetic temperature distribution probed by NH3
is in the fairly narrow range of 9 - 15 K. We find that cores within the
clusters IC348 and NGC1333 are significantly warmer than "field" starless
cores, and T_kin is higher within regions of larger extinction-derived column
density. Starless cores in the field are warmer when they are closer to class
O/I protostars, but this effect is not seen for those cores in clusters. For
field starless cores, T_kin is higher in regions in which the 13CO linewidth
and the 1.1mm flux from the core are larger, and T_kin is lower when the the
peak column density within the core and average volume density of the core are
larger. There is no correlation between T_kin and 13CO linewidth, 1.1mm flux,
density or peak column density for those cores in clusters. The temperature of
the cloud material along the line of sight to the core, as measured by CO or
far-infrared emission from dust, is positively correlated with core temperature
when considering the collection of cores in the field and in clusters, but this
effect is not apparent when the two subsamples of cores are considered
separately.Comment: Accepted to ApJ; 13 pages, including 3 tables and three figure
Action research and the study of human being
"Despite the openness of action research to engage with several philosophical
movements from the 20th century, there does not seem to be as much
engagement with existentialist thought. I try to point out and further
articulate certain affinities that I see between action research and existentialist
philosophy. I suggest that action research can gain from exploring
these connections. Based on the existentialist perspective, I compare
action research and more standard social science. In particular, I use
Heidegger’s notions of “das Man” and an “existentialist essence” of
human being as a key to bringing out these differences and for suggesting
ways in which action research may capitalize on such differences." (author's abstract
A Century of Faith and Victory (Original Transcript)
A history of Taylor University written by the Rev. Enoch A Bunner from the class of 1898 and presented in 1946 during the centennial celebration of Taylor University. This is the original typed transcript.https://pillars.taylor.edu/history_books/1043/thumbnail.jp
A Century of Faith and Victory (Later Transcript)
A history of Taylor University written by the Rev. Enoch A Bunner from the class of 1898 and presented in 1946 during the centennial celebration of Taylor University. This is a later transcript of the original transcript. Blank spaces correspond with typoes and unintelligible corrections in the original transcript.
The original transcript was from 1946 but this copy appears to be from the 1990s, though there are no dates on this document. It may have been retyped on the occasion of Enoch\u27s death in 1992.https://pillars.taylor.edu/history_books/1044/thumbnail.jp
A NEW GEOMETRIC MODEL AND METHODOLOGY FOR UNDERSTANDING PARSIMONIOUS SEVENTH-SONORITY PITCH-CLASS SPACE
Parsimonious voice leading is a term, first used by Richard Cohn, to describe non-diatonic motion among triads that will preserve as many common tones as possible, while limiting the distance traveled by the voice that does move to a tone or, better yet, a semitone. Some scholars have applied these principles to seventh chords, laying the groundwork for this study, which strives toward a reasonably comprehensive, usable model for musical analysis.
Rather than emphasizing mathematical proofs, as a number of approaches have done, this study relies on two- and three-dimensional geometric visualizations and spatial analogies to describe pitch-class and harmonic relationships. These geometric realizations are based on the organization of the neo-Riemannian Tonnetz, but they expand and apply the organizational principles of the Tonnetz to seventh sonorities. It allows for the descriptive “mapping” or prescriptive “navigation” of harmonic paths through a defined space.
The viability of the theoretical model is examined in analyses of passages from the repertoire of Frédéric Chopin. These passages exhibit a harmonic syntax that is often difficult to analyze as anything other than “tonally unstable” or “transitional.” This study seeks to analyze these passages in terms of what they are, rather than what they are not
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