A graph-based approach for assessing storm-induced coastal changes

Hurricanes and tropical storms are severe threats to coastal properties, settlements, and infrastructure. Airborne light detection and ranging (lidar) surveys conducted before and after storm events allow detailed analysis of coastal geomorphologic and sediment volumetric changes and have been proved very useful in the study of coastal changes. Traditionally, most studies use the pixel-based differencing method to quantify the spatial extent and magnitude of coastal changes based on sequential lidar surveys. This research presents a graph theory-based approach and associated software tools for representing and quantifying storm-induced damages to buildings, beaches and sand dunes, coastal vegetation canopy, and infrastructure. Generation of elevation difference grids, construction of local contour trees, and derivation of semantic properties are key components of the new algorithm for change object detection and extraction. An ontology and taxonomy are proposed to classify change objects into different types of coastal damages in terms of their semantic properties. This method has been successfully applied to assess damages of Hurricane Ike to the Bolivar Peninsula on the Texas Gulf Coast based on pre- and post-storm airborne lidar data and colour infrared aerial photographs.     

Corrosion of a stainless steel handrail

AISI 304 and 304L stainless steels are “workhores” grades of austenitic stainless steel frequently used in architectural applications, as well as in cookware, appliances, and numerous other applications where resistance to corrosion is required. This paper examines a corrosion failure (the appearance of rustlike stains on the surface) of a 304 stainless steel handrail that appears to have occurred as a result of contamination during the fabrication process.     

Student perspectives on mentoring in a science outreach project

Abstract

The focus of this paper is an examination of mentorship relationships developed as a result of six students’ participation in a local community science centre sponsored through an NSERC/CRYSTAL project. Each year, a number of students participate in after‐school activities sponsored by the community science centre. Much of this work involves a one‐to‐one approach, with a middle years or high school student working with a professor partner. The professor acts as a mentor to the student, facilitating learning in a manner not always feasible within a school setting with large class sizes. For some students this research may be the basis of a science fair project; for others if is simply a study based on individual interest. Mentored students were interviewed about the nature of that mentorship, with the goal of describing the experience from the students’ perspective. Questions focused on the student's experience of working with a mentor, including how the mentorship relationship was formed, what the importance of the voluntary nature of mentoring was, what the benefits and challenges of working with a mentor were, how the mentorship relationship affected the level of content knowledge the student gained, and what effect the mentoring relationship had on the student's continuing interest in science. The mentorship program offers students the opportunity to work within a developing community of practice.     

Categorization and communication in the face of prejudice: When describing perceptions changes what is perceived.

In the face of prejudice against an ingroup, common ground for communication exists when people use similar social categories to understand the situation. Three studies tested the hypothesis that describing perceptions of prejudice can fundamentally change those perceptions because communicators account for the common ground in line with conversational norms. When women (Study 1), African Americans (Study 2), and Americans (Study 3) simply thought about suspected prejudice against their ingroup, categorization guided their perceptions: Participants assimilated their views of the prejudiced event toward the perceptions of ingroup members but contrasted away from the perceptions of outgroup members. Conversely, when participants described their perceptions, they contrasted away from the given category information and actually arrived at the opposite perceptions as those who merely thought about the prejudiced event. Study 3 identified an important qualification of these effects by showing that they were obtained only when participants could assume their audience was familiar with the common ground. Implications are discussed for understanding the role of communication in facilitating and inhibiting collective action about prejudice. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Accounting for case manager effects in the evaluation of mental health services.

Three methods of accounting for case manager effects in tests of the efficacy of mental health services are explored. These methods include (1) treating the case manager as a fixed factor, (2) treating the case manager as a random factor, and (3) examining service effects within the case manager. They are demonstrated with data from a nationally known case management program serving individuals with serious and persistent mental illness. Specifically, 3 conceptually distinct types of services provided or brokered by case managers are identified: habilitation-rehabilitation, community support, and traditional psychiatric services. The effectiveness of each in improving clients' adjustment is then examined with multiple regression adjustment strategies and each of the 3 methods to account for case manager effects. The results provide strong support for effects attributable to case managers and some support for the efficacy of habilitation-rehabilitation and community support services beyond the effects of traditional psychiatric services. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Note of clarification on Scholten and Sherman (2006): Erratum.

Reports an error in "Tradeoffs and Theory: The Double-Mediation Model" by Marc Scholten and Steven J. Sherman (Journal of Experimental Psychology: General, 2006 May, Vol 135[2], 237-261). This article was inadvertently printed with the incorrect title. The original title was "Tradeoffs and Conflict: The Double-Mediation Model." This title highlights the relation between tradeoffs and conflict as investigated by the authors and accounted for by their model. However, readers are asked to refer to the article by the title with which it was printed to facilitate its retrieval.. (The following abstract of the original article appeared in record 2006-06642-006.) Most theories of decision making suggest that, when options imply tradeoffs between their attributes, conflict increases as tradeoff size increases, because greater sacrifices are to be incurred in choosing one option instead of another. An alternative view is that conflict decreases as tradeoff size increases, because stronger arguments can be made for any decision. The authors propose a unified model, the double-mediation model, which combines the mediating effects of sacrifice and argumentation. Our model generally predicts an inverse U-shaped relation between tradeoff size and conflict. Results support this prediction. Also, when the decision situation increases the mediating effect of sacrifice relative to that of argumentation, the relation between tradeoff size and conflict changes in an upward direction; conversely, when the decision situation increases the mediating effect of argumentation relative to that of sacrifice, the relation changes in a downward direction. Results support these predictions as well. Commonalities and differences between our model and other formulations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Scopolamine impairs human recognition memory: Data and modeling.

Eight subjects studied a set of complex visual images after administration of 0.4 mg scopolamine. Another 8 subjects performed the same task without drug administration. On a subsequent item recognition test, subjects rated, on a 5-point scale, their confidence that the studied pictures and an equal number of unstudied lures were actually presented. Results showed that scopolamine affected responses to studied items, but not unstudied lures, demonstrating an unambiguous effect of scopolamine on recognition memory. To describe the scopolamine-injected subjects' data, the authors constructed a new model of 2-process recognition that includes the A. P. Yonelinas (1994) model as a limiting case. The model analysis suggests that scopolamine affected both familiarity and recollection. In particular, scopolamine did not affect the frequency with which recollection took place, but rather, affected the amount of recollected information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)