Many high-level security requirements are about the allowed flow of information in programs, but are difficult to make precise because they involve selective downgrading. Quite a few mutually incompatible and ad-hoc approaches have been proposed for specifying and enforcing downgrading policies. Prior surveys of these approaches have not provided a unifying technical framework. Notions from epistemic logic have emerged as a good approach to policy semantics but are considerably removed from well developed static and dynamic enforcement techniques. We develop a unified framework for expressing, giving meaning and enforcing information downgrading policies that builds on commonly known and widely deployed concepts and techniques, especially static and dynamic assertion checking. These concepts should make information flow accessible and enable developers without special training to specify precise policies. The unified framework allows to directly compare different policy specification styles and enforce them by leveraging existing techniques.
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This content will become publicly available on February 1, 2025
Color Semantics in Human Cognition
People have associations between colors and concepts that influence the way they interpret color meaning in information visualizations (e.g., charts, maps, diagrams). These associations are not limited to concrete objects (e.g., fruits, vegetables); even abstract concepts, like sleeping and driving, have systematic color-concept associations. However, color-concept associations and color meaning (color semantics) are not the same thing, and sometimes they conflict. This article describes an approach to understanding color semantics called the color inference framework. The framework shows how color semantics is highly flexible and context dependent, which makes color an effective medium for communication.
more » « less- Award ID(s):
- 1945303
- PAR ID:
- 10516638
- Publisher / Repository:
- Sage Journals
- Date Published:
- Journal Name:
- Current Directions in Psychological Science
- Volume:
- 33
- Issue:
- 1
- ISSN:
- 0963-7214
- Page Range / eLocation ID:
- 58 to 67
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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