6,563 research outputs found
Operads within monoidal pseudo algebras
A general notion of operad is given, which includes as instances, the operads
originally conceived to study loop spaces, as well as the higher operads that
arise in the globular approach to higher dimensional algebra. In the framework
of this paper, one can also describe symmetric and braided analogues of higher
operads, likely to be important to the study of weakly symmetric, higher
dimensional monoidal structures
New Jersey Charter Schools: A Data-Driven View, Part I
Policy makers cannot make informed decisions about the regulation of charter schools without first considering the characteristics of the students who are enrolled in these schools. This report -- the first in a three-part series on New Jersey charter schools -- uses publicly available data to explore the differences found between the student populations of charter schools and those of their host districts
Learning by Seeing by Doing: Arithmetic Word Problems
Learning by doing in pursuit of real-world goals has received much attention from education researchers but has been unevenly supported by mathematics education software at the elementary level, particularly as it involves arithmetic word problems. In this article, we give examples of doing-oriented tools that might promote children\u27s ability to see significant abstract structures in mathematical situations. The reflection necessary for such seeing is motivated by activities and contexts that emphasize affective and social aspects. Natural language, as a representation already familiar to children, is key in these activities, both as a means of mathematical expression and as a link between situations and various abstract representations. These tools support children\u27s ownership of a mathematical problem and its expression; remote sharing of problems and data; software interpretation of children\u27s own word problems; play with dynamically linked representations with attention to children\u27s prior connections; and systematic problem variation based on empirically determined level of difficulty
A Theory on the Convective Origins of Active Longitudes on Solar-like Stars
Using a thin flux tube model in a rotating spherical shell of turbulent,
solar-like convective flows, we find that the distribution of emerging flux
tubes in our simulation is inhomogeneous in longitude, with properties similar
to those of active longitudes on the Sun and other solar-like stars. The
large-scale pattern of flux emergence our simulations produce exhibits
preferred longitudinal modes of low order, drift with respect to a fixed
reference system, and alignment across the Equator at low latitudes between 15
degrees. We suggest that these active-longitude-like emergence patterns are the
result of columnar, rotationally aligned giant cells present in our convection
simulation at low latitudes. If giant convecting cells exist in the bulk of the
solar convection zone, this phenomenon, along with differential rotation, could
in part provide an explanation for the behavior of active longitudes.Comment: This paper was accepted to The Astrophysical Journal on May 6, 201
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