Journalistic sketches, taxonomies, mathematical models, broad multivariate approaches, and modest distinctions together show a variety of possible foci and levels of approach to the topic of crowding. This review organizes crowding theory into four orientations. First, a number of seminal theories in the ethological perspective are reviewed, including Calhoun's social interaction models, Lorenz's model, Wynne-Edwards's community self-regulation theory, and Leyhausen's theory. Second, theories of temporary street crowds are discussed, including early conceptualizations and attempts to explain the crowds' formation, structure, and internal processes. Third, comprehensive equilibrium models of crowding are described, including Altman's and Stokols's models and Manderscheid's theory. Fourth, a number of diverse limited conceptualizations are reviewed, including Milgram's overload hypothesis, Esser's biosocial approach, Freedman's density–intensity theory, and Wicker's theory of overmanning. Definitional problems are also discussed.
Robust precision attitude tracking of an uncertain rigid spacecraft based on regulation theory
