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  1. The excitation of low frequency dust acoustic (or dust density) waves in a dusty plasma can be driven by the flow of ions relative to dust. We consider the nonlinear development of the ion–dust streaming instability in a highly collisional plasma, where the ion and dust collision frequencies are a significant fraction of their corresponding plasma frequencies. This collisional parameter regime may be relevant to dusty plasma experiments under microgravity or ground-based conditions with high gas pressure. One-dimensional particle-in-cell simulations are presented, which take into account collisions of ions and dust with neutrals, and a background electric field that drivesmore »the ion flow. Ion flow speeds of the order of a few times thermal are considered. Waveforms of the dust density are found to have broad troughs and sharp crests in the nonlinear phase. The results are compared with the nonlinear development of the ion–dust streaming instability in a plasma with low collisionality.« less
  2. Tropical coral reef ecosystems in the Pacific region are degrading rapidly as ocean temperatures rise and local anthropogenic stressors increase. In this context of rapid change, effective site-based management of coral reef fisheries necessitates flexible environmental governance that is closely attuned to the needs of multiple stakeholders who depend on the fishery for income, food, and cultural identity. As such, many practitioners and scholars call for adaptive co-management of coral reef fisheries where local resource users play a primary role in environmental governance with the support of flexible institutions that operate across organizational scales. This article describes the history andmore »evaluates the current status of marine governance in Moorea, French Polynesia. Established in 2004, the management framework is under revision because it has failed to meet its ecological objectives and has generated discontent among many stakeholders. Drawing on household surveys, interviews, and archival information, the challenges to as well as the factors that may enable a more successful transition of the current governance arrangement towards co-management are detailed. It is argued that recent social mobilization, subsistence and cultural links to the fishery, the presence of geographically and socially relevant traditional governance boundaries, and the implementation of co-management in other parts of French Polynesia are positive factors. However, lack of trust between stakeholders, social heterogeneity, disruption of traditional cultural institutions and practices, minimal institutional support, and an uncertain legal framework suggest that there are significant headwinds for maneuvering towards successful co-management in Moorea.« less
  3. Surveys often are used in educational research to gather information about respondents without considering the effect of survey questions on survey-takers themselves. Does the very act of taking a survey influence perspectives, mindsets, and even behaviors? Does a survey itself effectuate attitudinal change? Such effects of surveys, and implications for survey data interpretation, warrant close attention. There is a long tradition of research on surveys as behavioral interventions within political science and social psychology, but limited attention has been given to the topic in engineering education, and higher education more broadly. Recently the engineering education community has started to examinemore »the potential effects of assessment techniques (including surveys) as catalysts for reflection. In March 2014, the Consortium to Promote Reflection in Engineering Education (CPREE), representing a two-year collaboration amongst 12 campuses, was established to promote “a broader understanding and use of reflective techniques in engineering education.”1 CPREE’s formation suggests a growing recognition of reflection as an important and underemphasized aspect of an engineer’s education. CPREE defines reflection as “exploring the meaning of experiences and the consequences of the meanings for future action” and emphasizes the importance of taking action as a result of ascribing meaning to experiences.1 Surveys may be one of several tools that may create opportunities for reflection; others include “exam wrappers” and “homework wrappers” that encourage students to explore how they feel about an assignment or task as part of making meaning of it2,3 (and stimulating the kind of reflection that can lead to action). The current study bridges these two frameworks of behavioral interventions and reflection to consider the “extra-ordinate” dimensions of survey-taking and explores how survey participation may (1) support students’ reflection on past experiences, meaningmaking of these experiences, and insights that “inform [their] path going forward,”1 and (2) be associated with students’ subsequent behaviors. We first review a broader literature on the interventional effects on surveys in political studies and social psychology, after which we present the results obtained from including an optional reflection question at the end of an engineering education survey. We conclude that educators would benefit from considering the range of potential impacts that responding to questions may have on students’ thoughts and actions, rather than treating surveys as neutral data collection devices when designing their research.« less