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Although they play a key role in shaping local efforts, there is limited research on how city officials define sustainability as it is practiced in their communities. To address this limitation and contribute to planning research, we leveraged a unique nationwide data set of sustainability definitions provided by the sustainability lead in more than 400 U.S city governments. Our study’s qualitative analysis of these statements complements existing research by exploring emerging themes on how sustainability is perceived and practiced at the local level. Results indicated that practitioners’ conceptualizations reflected five general orientation categories: action, aspiration, emotion, process and organization, and progress. We evaluated the association of these general orientation categories with cities’ administrative arrangements, political environments, resources, and capacities. Findings suggested that supportive contexts were associated with city sustainability staff defining sustainability in aspirational terms, as opposed to emphasizing progress or discrete actions.
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OPTIMAL LINE PACKINGS FROM FINITE GROUP ACTIONS
We provide a general program for finding nice arrangements of points in real or complex projective space from transitive actions of finite groups. In many cases, these arrangements are optimal in the sense of maximizing the minimum distance. We introduce our program in terms of general Schurian association schemes before focusing on the special case of Gelfand pairs. Notably, our program unifies a variety of existing packings with heretofore disparate constructions. In addition, we leverage our program to construct the first known infinite family of equiangular lines with Heisenberg symmetry.
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- PAR ID:
- 10176917
- Date Published:
- Journal Name:
- Forum of Mathematics, Sigma
- Volume:
- 8
- ISSN:
- 2050-5094
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/fms.2019.48
