Simple structures with complex symmetry
نویسندگان
چکیده
منابع مشابه
Simple Structures with Complex Symmetry
We define the automorphism spectrum of a computable structure M, a measurement of the complexity of the symmetries of M, and prove that certain sets of Turing degrees can be realized as automorphism spectra, while certain others cannot.
متن کاملOn Symmetry of Some Nano Structures
It is necessary to generate the automorphism group of a chemical graph in computer-aided structure elucidation. An Euclidean graph associated with a molecule is defined by a weighted graph with adjacency matrix M = [dij], where for i≠j, dij is the Euclidean distance between the nuclei i and j. In this matrix dii can be taken as zero if all the nuclei are equivalent. Otherwise, one may introduce...
متن کاملEvent Structures with Symmetry
A category of event structures with symmetry is introduced and its categorical properties investigated. Applications to the event-structure semantics of higher order processes, nondeterministic dataflow and the unfolding of Petri nets with multiple tokens are sketched.
متن کاملThe Effect of Textual Enhancement Types on EFL Learners’ Grammatical Awareness of Simple and Complex Structures
The purpose of this study was to investigate the effect of textual enhancement types on English as Foreign Language ( EFL ) learn er s ’ grammatical awareness of simple and complex structures. A nu m- ber of 104 learners from Ayandegan Institute, in Tehran, participated in this study. To homogenize the samples, the researchers administered a placement Michigan Test of English language to the p...
متن کاملCalculation of Buckling Load and Eigen Frequencies for Planar Truss Structures with Multi-Symmetry
In this paper, the region in which the structural system is situated is divided into four subregions, namely upper, lower, left and right subregions. The stiffness matrix of the entire system is then formed and using the existing direct symmetry and reverse symmetry, the relationships between the entries of the matrix are established. Examples are included to illustrate the steps of the method.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Algebra and Logic
سال: 2010
ISSN: 0002-5232,1573-8302
DOI: 10.1007/s10469-010-9079-4