2,741 research outputs found
Continuation of tailored composite structures of ordered staple thermoplastic material
The search for the cost effective composite structure has motivated the investigation of several approaches to develop composite structure from innovative material forms. Among the promising approaches is the conversion of a planar sheet to components of complex curvature through sheet forming or stretch forming. In both cases, the potential for material stretch in the fiber direction appears to offer a clear advantage in formability over continuous fiber systems. A framework was established which allows the simulation of the anisotropic mechanisms of deformation of long discontinuous fiber laminates wherein the matrix phase is a viscous fluid. Predictions for the effective viscosities of a hyper-anisotropic medium consisting of collimated, discontinuous fibers suspended in viscous matrix were extended to capture the characteristics of typical polymers including non-Newtonian behavior and temperature dependence. In addition, the influence of fiber misorientation was also modeled by compliance averaging to determine ensemble properties for a given orientation distribution. A design tool is presented for predicting the effect of material heterogeneity on the performance of curved composite beams such as those used in aircraft fuselage structures. Material heterogeneity can be induced during manufacturing processes such as sheet forming and stretch forming of thermoplastic composites. This heterogeneity can be introduced in the form of fiber realignment and spreading during the manufacturing process causing radial and tangential gradients in material properties. Two analysis procedures are used to solve the beam problems. The first method uses separate two-dimensional elasticity solutions for the stresses in the flange and web sections of the beam. The separate solutions are coupled by requiring that forces and displacements match section boundaries. The second method uses an approximate Rayleigh-Ritz technique to find the solutions for more complex beams. Analyses are performed for curved beams of various cross-sections loaded in pure bending and with a uniform distributed load. Preliminary results show that the geometry of the beam dictates the effect of heterogeneity on performance. The role of heterogeneity is larger in beams with a small average radius-to-depth ration, R/t, where R is the average radius of the beam and t is the difference between the inside and outside radii. Results of the anlysis are in the form of stresses and displacements and are compared to both mechanics of materials and numerical solutions obtained using finite element analysis
Review of Anatomy of a Revived Church: Seven Findings of How Congregations Avoided Death, byThom S. Rainer
Topic Modeling
Given the growing recognition of the role of teachers as agents in 21st century learning environments, this proposed study builds on our work on ‘Teacher Design Knowledge’ (TDK) as critical capabilities for teachers in designing and implementing innovative curriculum, pedagogy, and technology through researcher-practitioner collaboration (SSHRC Insight Grant 2017-2024, Kim, M. S., PI). As one of TDK competencies, teacher data literacies (TDL), the ability to derive meaningful information from multimodal data (e.g., drawings, 3D modeling, gaze, gestures, emotions) in student learning, is a relatively new concept for teachers in contexts of cultural and linguistic diversity. Although the COVID-19 pandemic has accelerated digital transformation of education, most research methodological tools in data literacies have been still predominantly focusing on pre-collected datasets of written texts. Educational researchers have increasingly called for adapting research methodologies to analyze real-world, ecological, and multimodal datasets from culturally and linguistically diverse (CLD) students. There has been no consensus in research methods in multimodal data of CLD students. To respond to these challenges, this study utilizes a topic modeling approach TowaRds Automated aNalySis of research Methods In Teacher daTa Literacies (\u27TRANSMITTAL\u27)
The Influence of Culture on Behavior-Based Tasks of Impulsivity
Background: Among Latinx youth residing in the United States (U.S), the adoption of U.S cultural behaviors, values, and identity has been proposed to increase risk for negative outcomes, such as substance use. Research also suggests that the maintenance of Latinx cultural behaviors, values, and identity may be protective. Although there is an established link between impulsivity and substance use outcomes, very little research has sought to explore factors that influence impulsivity among Latinx groups. Furthermore, behavioral tasks have made substantial contributions as measures of impulsivity, yet few studies have examined cultural identity domains in relation to these behavioral tasks.
Objective: The aim of this study was to investigate relationships between cultural domains (i.e., behaviors, values, and identifications) of cultural identity and performance on behavior-based measures of impulsivity among a population of Latinx adolescents and emerging adults.
Methods: Latinx adolescents (N = 92) between the ages of 13-18 and Latinx emerging adults (N = 278) between the ages of 18 and 25 were recruited for the present study. It was hypothesized that psychological domains of cultural identity, including ethnic identity, language use, self-construal, and familism values would be associated with lower preference for smaller more immediate rewards on the MCQ, higher preference for the less-risky reward on the PDQ, and increased levels of inhibitory control on the Flanker task. It was also hypothesized that Latinx participants who receive the family obligation/interdependent self-construal prime would have reduced rates of delay discounting and increased rates of probability discounting.
Results: The current study found increased levels of comfort related to one’s bicultural identity to be associated with increased inhibitory control on the Flanker task for adolescents, but lower rates of probability discounting (i.e., preference for riskier option) on the PDQ for young adults. Spanish language use was found to be significantly associated with lower rates of delay discounting (i.e., preference for larger delayed rewards) on the MCQ and this association was unique to young adults. No significant effect as a result of cultural prime condition was observed
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