4,752 research outputs found
An interactive graphics package for the automatic node renumbering of finite element matrices
An interactive graphics software package which allows users to display the non-zero structure of large sparse symmetric materials was described and methods used to implement it as a portable FORTRAN callable subroutine were summarized. In particular, the system permits the display of the resulting matrix after reordering the rows and columns, with the reordering scheme either defined by the user or automatically generated by the program with the aim of reducing matrix bandwidth and profile. Although the primary application of the package has been to the finite element analysis of structures, it is equally well suited to the many other areas of engineering and science which use sparse matrices
Alien Registration- Boisvert, Henry W. (Lewiston, Androscoggin County)
https://digitalmaine.com/alien_docs/30698/thumbnail.jp
Explaining Changes in the Distribution of Annual Dairy Farm Income over Time
This paper identifies factors affecting the distribution of farm income among dairy producers over time. Using data from participants in Cornell's Dairy Farm Record Program, we decompose differences of farm income distributions into those due to: differences in means of observable farm characteristics, differential marginal effects of characteristics and unobserved random error. The distribution of farm income is affected by factors reflecting the operators' experience and investment in human capital and indicators of management efficiency and level of capital investment. The marked changes in marginal contributions of these factors explain most of the total change in the distribution of income.Dairy farm income distribution, Decomposition, Farm Management, Livestock Production/Industries,
Developing numerical libraries in Java
The rapid and widespread adoption of Java has created a demand for reliable
and reusable mathematical software components to support the growing number of
compute-intensive applications now under development, particularly in science
and engineering. In this paper we address practical issues of the Java language
and environment which have an effect on numerical library design and
development. Benchmarks which illustrate the current levels of performance of
key numerical kernels on a variety of Java platforms are presented. Finally, a
strategy for the development of a fundamental numerical toolkit for Java is
proposed and its current status is described.Comment: 11 pages. Revised version of paper presented to the 1998 ACM
Conference on Java for High Performance Network Computing. To appear in
Concurrency: Practice and Experienc
Animal-Assisted Play: A Strategy for Promoting Children’s Physical Activity Play
This article explores how animal-assisted play might be used as a strategy in playwork to support children’s right to play, enrich their play experiences, encourage their physical activity play and better their health and life quality. Children’s interactions with pets or companion animals in free play or animal-assisted activities (AAA) can yield therapeutic benefits by increasing physical and mental health and well-being and also offer possibilities for more outdoor play, agency, risk-taking, fun and enjoyment, as well as high-quality play experiences. We invite playwork practitioners to consider the important role of animals in children’s lives and the potential value of animal-assisted play in creating opportunities for enriching children’s play and life quality
Surface diffusion coefficients by thermodynamic integration: Cu on Cu(100)
The rate of diffusion of a Cu adatom on the Cu(100) surface is calculated
using thermodynamic integration within the transition state theory. The results
are found to be in excellent agreement with the essentially exact values from
molecular-dynamics simulations. The activation energy and related entropy are
shown to be effectively independent of temperature, thus establishing the
validity of the Arrhenius law over a wide range of temperatures. Our study
demonstrates the equivalence of diffusion rates calculated using thermodynamic
integration within the transition state theory and direct molecular-dynamics
simulations.Comment: 4 pages (revtex), two figures (postscript
Diffusion of Pt dimers on Pt(111)
We report the results of a density-functional study of the diffusion of Pt
dimers on the (111) surface of Pt. The calculated activation energy of 0.37 eV
is in {\em exact} agreement with the recent experiment of Kyuno {\em et al.}
\protect{[}Surf. Sci. {\bf 397}, 191 (1998)\protect{]}. Our calculations
establish that the dimers are mobile at temperatures of interest for adatom
diffusion, and thus contribute to mass transport. They also indicate that the
diffusion path for dimers consists of a sequence of one-atom and (concerted)
two-atom jumps.Comment: Pour pages postscript formatted, including one figure; submitted to
Physical Review B; other papers of interest can be found at url
http://www.centrcn.umontreal.ca/~lewi
Long-Period Giant Companions to Three Compact, Multiplanet Systems
Understanding the relationship between long-period giant planets and multiple smaller short-period planets is critical for formulating a complete picture of planet formation. This work characterizes three such systems. We present Kepler-65, a system with an eccentric (e = 0.28 ± 0.07) giant planet companion discovered via radial velocities (RVs) exterior to a compact, multiply transiting system of sub-Neptune planets. We also use precision RVs to improve mass and radius constraints on two other systems with similar architectures, Kepler-25 and Kepler-68. In Kepler-68 we propose a second exterior giant planet candidate. Finally, we consider the implications of these systems for planet formation models, particularly that the moderate eccentricity in Kepler-65\u27s exterior giant planet did not disrupt its inner system
An Unobscured type II quasar candidate: SDSS J012032.19-005501.9
We report the finding of an unobscured type II Active Galactic Nuclei (AGN)
candidate, SDSS J012032.19-005501.9 at a relatively high redshift of
0.601,which shows a number of unusual properties. It varies significantly on
timescales of years as typical type I AGNs and marginally on timescales of
weeks. The color-magnitude relation and the structure function are also
consistent with that of type I AGNs, which imply that its variability likely
originates from the black hole accretion system .However, no broad emission
line is detected in the SDSS spectrum, and the upper limit of the equivalent
width of the H broad emission line is much less than that of type I
AGNs. These properties suggest that SDSS J012032.19-005501.9 may be an
unobscured quasar without broad emission lines intrinsically, namely an
unobscured type II AGN or "true" type II AGN. Furthermore, its continuum
luminosity is at least one order of magnitude fainter than the average value of
thepast century expected from the [OIII] emission line. It indicates that SDSS
J012032.19-005501.9 may be switching off. Additional possible scenarios to
explain this intriguing source are also discussed. Future deep observations at
multi-wavelengths are needed to reveal the nature of this peculiar and
intriguing AGN.Comment: 8 pages, 7 figures, 1 table, accepted for publication in The
Astronomical Journa
- …