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Chicago, IL, United States

Illinois Institute of Technology, commonly called Illinois Tech or IIT, is a private Ph.D.-granting research university located in Chicago, in the U.S. state of Illinois, with programs in engineering, science, psychology, architecture, business, communications, industrial technology, information technology, design and law. Wikipedia.

Qian X.,Illinois Institute of Technology
Computer Methods in Applied Mechanics and Engineering | Year: 2010

Non-uniform rational B-spline (NURBS) has been widely used as an effective shape parameterization technique for structural optimization due to its compact and powerful shape representation capability and its popularity among CAD systems. The advent of NURBS based isogeometric analysis has made it even more advantageous to use NURBS in shape optimization since it can potentially avoid the inaccuracy and labor-tediousness in geometric model conversion from the design model to the analysis model.Although both positions and weights of NURBS control points affect the shape, until very recently, usually only control point positions are used as design variables in shape optimization, thus restricting the design space and limiting the shape representation flexibility.This paper presents an approach for analytically computing the full sensitivities of both the positions and weights of NURBS control points in structural shape optimization. Such analytical formulation allows accurate calculation of sensitivity and has been successfully used in gradient-based shape optimization.The analytical sensitivity for both positions and weights of NURBS control points is especially beneficial for recovering optimal shapes that are conical e.g. ellipses and circles in 2D, cylinders, ellipsoids and spheres in 3D that are otherwise not possible without the weights as design variables. © 2010 Elsevier B.V. Source

Qian X.,Illinois Institute of Technology
Computer Methods in Applied Mechanics and Engineering | Year: 2013

In this paper, we present a new form of density based topology optimization where the design space is restricted to the B-spline space. An arbitrarily shaped design domain is embedded into a rectangular domain in which tensor-product B-splines are used to represent the density field. We show that, with proper choice of B-spline degrees and knot spans, the B-spline design space is free from checkerboards without extraneous filtering or penalty. We further reveal that the B-spline representation provides an intrinsic filter for topology optimization where the filter size is controlled by B-spline degrees and knot spans. This B-spline filter is effective in removing numerical artifacts and controlling minimal feature length in optimized structures when the B-spline basis functions span multiple analysis elements. We demonstrate that the B-spline filter is linear in storage cost and does not require neighboring element information. Further, this B-spline based density representation decouples the design representation of density distribution from the finite element mesh thus multi-resolution designs can be obtained without re-meshing the design domain. In particular, successive optimization with respect to design resolutions leads to topologically simple features obtainable in either coarse or fine design resolutions, thus achieving a form of mesh independency with respect to design representation. This approach is versatile in the sense a variety of finite element and isogeometric analysis techniques can be used for solution of equilibrium equations and a variety of projection methods can be used to approximate B-spline density in analysis. Numerical studies have been conducted over several representative topology optimization problems, including minimal compliance of MBB beams, compliant mechanism inverters, and heat conductions. © 2013 Elsevier B.V. Source

Corrigan P.W.,Illinois Institute of Technology
World Psychiatry | Year: 2016

Advocates and scientists have partnered to develop and evaluate programs meant to erase the egregious effects of the different forms of stigma. Enough evidence has been collected to yield lessons about approaches to stigma change. Some of the most insightful of these lessons emerge from unintended consequences of good intentioned approaches, and are the focus of this paper. They include the limited benefits of education especially when compared to contact, beating stigma is more than changing words, beware pity as a message, understand the competing agendas of stigma change, replace ideas of normalcy with solidarity, and avoid framing self-stigma as the problem of people with mental illness and not of society. The paper ends with consideration of the back seat role that psychiatrists and other mental health providers should have in stigma change. Source

Otterbacher J.,Illinois Institute of Technology
Journal of Computer-Mediated Communication | Year: 2011

Review communities typically display contributions in list format, using participant feedback in determining presentation order. Given the volume of contributions, which are likely to be seen? While previous work has focused on content, we examine the relationship between communication tactics and prominence. We study three communities, comparing front-page reviews versus those on latter pages. We consider 3 types of devices: structural features, textual features, and persuasive writing. Structural features, such as profiles, convey information about authors. Textual properties, such as punctuation use, can make an impression on others. Rhetorical writing strategies are used by reviewers to convince readers of their opinions. When controlling for content, the most salient tactics distinguishing prominent reviews are textual properties and persuasive language. © 2011 International Communication Association. Source

Corrigan P.W.,Illinois Institute of Technology
Psychiatric Services | Year: 2012

Advocates and social marketers have used substantial resources to develop public service announcements (PSAs) as a lead strategy in public education and awareness campaigns meant to eliminate stigma associated with mental illness. Evaluations of PSAs are needed to determine whether this is a good investment. The author notes that very few studies have been reported in the peer-reviewed medical and psychological research literature addressing this question. Reports of government contractors suggest that PSAs have some effect as measured by population penetration, but such data provide no meaningful evidence about the impact of PSAs, such as real-world change in prejudicial attitudes and discriminatory behaviors. The author considers reasons for the limited impact of PSAs and proposes that social marketing campaigns could enhance their impact by targeting local groups. Source

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