78,174 research outputs found
Magnetically operated limit switch has improved reliability, minimizes arcing
Limit switch for reliable, low-travel, snap action with negligible arcing uses an electrically nonconductive permanent magnet consisting of a ferrimagnetic ceramic and ferromagnetic pole shoes which form a magnetic and electrically conductive circuit with a ferrous-metal armature
Logos I - Philosophy and the Nature of Morality: The Abolition of Man, C.S. Lewis
C.S. Lewis’ objective stance on ethics is argued to be superior to the moral sentimentalism of David Hume, because if there is not agreement on what constitutes moral action, then there is no basis for argument over the existence of moral law
Thin fillers in the cubical nerves of omega-categories
It is shown that the cubical nerve of a strict omega-category is a sequence
of sets with cubical face operations and distinguished subclasses of thin
elements satisfying certain thin filler conditions. It is also shown that a
sequence of this type is the cubical nerve of a strict omega-category unique up
to isomorphism; the cubical nerve functor is therefore an equivalence of
categories. The sequences of sets involved are in effect the analogues of
cubical T-complexes appropriate for strict omega-categories. Degeneracies are
not required in the definition of these sequences, but can in fact be
constructed as thin fillers. The proof of the thin filler conditions uses chain
complexes and chain homotopies.Comment: Revised version to appear in Theory and Applications of Categories;
changed terminology; additional figures, examples and references; 27 page
Bots vs. Wikipedians, Anons vs. Logged-Ins
Wikipedia is a global crowdsourced encyclopedia that at time of writing is
available in 287 languages. Wikidata is a likewise global crowdsourced
knowledge base that provides shared facts to be used by Wikipedias. In the
context of this research, we have developed an application and an underlying
Application Programming Interface (API) capable of monitoring realtime edit
activity of all language versions of Wikipedia and Wikidata. This application
allows us to easily analyze edits in order to answer questions such as "Bots
vs. Wikipedians, who edits more?", "Which is the most anonymously edited
Wikipedia?", or "Who are the bots and what do they edit?". To the best of our
knowledge, this is the first time such an analysis could be done in realtime
for Wikidata and for really all Wikipedias--large and small. Our application is
available publicly online at the URL http://wikipedia-edits.herokuapp.com/, its
code has been open-sourced under the Apache 2.0 license.Comment: Poster at the Web Science Track of the 23rd International World Wide
Web Conference (WWW2014), Seoul, Kore
The algebraic structure of the universal complicial sets
The nerve of a strict omega-category is a simplicial set with additional
structure, making it into a so-called complicial set, and strict
omega-categories are in fact equivalent to complicial sets. The nerve functor
is represented by a sequence of strict omega-categories, called orientals,
which are associated to simplexes. In this paper we give a detailed algebraic
description of the morphisms between orientals. The aim is to describe
complicial sets algebraically, by operators and equational axioms.Comment: 25 pages. As to appear in Journal of Pure and Applied Algebra. Minor
corrections, addtional explanations, some propositions reclassified as lemma
A study of the relatioship between job satisfaction and educational preparation
Thesis (M.S.)--Boston Universit
Complicial structures in the nerves of omega-categories
It is known that strict omega-categories are equivalent through the nerve functor to complicial sets and to sets with complicial identities. It follows that complicial sets are equivalent to sets with complicial identities. We discuss these equivalences. In particular we give a conceptual proof that the nerves of omega-categories are complicial sets, and a direct proof that complicial sets are sets with complicial identities
- …