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991.
Students with autism spectrum disorder (ASD) have vastly different educational needs. Although some students with ASD may perform well across subjects within the general education classroom, other students with ASD may need more individualized support outside of the classroom. Historically, ASD assessments in schools have primarily focused on the measurement of cornerstone behaviors of ASD such as deficits in social communication and restricted or repetitive behaviors while underestimating the focus of academic skills even though both factors are required in the evaluation process and for an eligibility classification. The purpose of this article is to provide an overview of academic assessment practices in the schools by highlighting best practices in ASD evaluation, outlining ASD academic profiles and how to identify academic skill deficits, and reviewing the available literature that comes from different formal- and function-based assessment practices that are commonly used in schools today. The authors also discuss how formal- and function-based assessments both serve a purpose and are recommended to be used in conjunction with one another to best demonstrate a student's academic profile. Practitioners are ultimately encouraged to use a multi-informant, multi-modal approach when it comes to psychoeducational evaluations for individuals with ASD as it is evident that an individualized approach is essential due to the discrepancy of academic profiles related to this disability category as well as understanding that no measure is a perfect representation of any one skill.  相似文献   
992.
993.
In recent years, there has been a strong push to transform STEM education at K-12 and collegiate levels to help students learn to think like scientists. One aspect of this transformation involves redesigning instruction and curricula around fundamental scientific ideas that serve as conceptual scaffolds students can use to build cohesive knowledge structures. In this study, we investigated how students use mass balance reasoning as a conceptual scaffold to gain a deeper understanding of how matter moves through biological systems. Our aim was to lay the groundwork for a mass balance learning progression in physiology. We drew on a general models framework from biology and a covariational reasoning framework from math education to interpret students' mass balance ideas. We used a constant comparative method to identify students' reasoning patterns from 73 interviews conducted with undergraduate biology students. We helped validate the reasoning patterns identified with >8000 written responses collected from students at multiple institutions. From our analyses, we identified two related progress variables that describe key elements of students' performances: the first describes how students identify and use matter flows in biology phenomena; the second characterizes how students use net rate-of-change to predict how matter accumulates in, or disperses from, a compartment. We also present a case study of how we used our emerging mass balance learning progression to inform instructional practices to support students' mass balance reasoning. Our progress variables describe one way students engage in three dimensional learning by showing how student performances associated with the practice of mathematical thinking reveal their understanding of the core concept of matter flows as governed by the crosscutting concept of matter conservation. Though our work is situated in physiology, it extends previous work in climate change education and is applicable to other scientific fields, such as physics, engineering, and geochemistry.  相似文献   
994.
The focus on identity in the field of teaching and learning continues to grow, especially when it concerns equitable outcomes for students. While most attention is placed on students' identities and increasingly those of teachers, lesser addressed are the identities of the teacher educators and researchers broaching the issue of identity. Additionally, identity research is not often linked to relationships between self, others, and transformative action. We recognize these as gaps to be addressed and offer critical positional praxis (CPP) as a response. CPP is the public manifestation of the insights gained through our sense of identity and reflexivity. More specifically, CPP is the actions (or inactions) that express who we are in response to an event in any given social context—especially oppressive ones. In this article, we draw from our own critical autoethnographies, as a context for putting CPP into practice in identity research. Our collective analysis of these critical autoethnographies revealed how our identity development was inseparable from the ways in which we have each resisted the politics of domestication. Our autoethnographies further point to the role of dissent as central to our experiences of becoming critical science teacher educators committed to equity, diversity, and anti-racism in education. We draw from this analysis to offer recommendations for how identity and positionality can move beyond theoretical constructs toward transformative personal and collective change in science education.  相似文献   
995.
This paper presents a solution to the problem of global exact output tracking for uncertain MIMO (multiple-input–multiple-output) linear plants with non-uniform arbitrary relative degree using output feedback sliding mode control. The key idea to overcome the relative degree obstacle is to generalize our previous hybrid estimation scheme to a multivariable version by combining, through switching, a standard linear lead filter with a non-linear one based on robust exact differentiators, achieving uniform global exponential practical stability and exact tracking.  相似文献   
996.
In this paper strict, non-smooth Lyapunov functions for some non-homogeneous versions of the super-twisting algorithm are proposed. Convergence under the action of bounded perturbations for two basic forms of non-homogeneous algorithms will be studied by means of the Lyapunov functions. Since the homogeneity property cannot be used directly to prove stability of the algorithms, the availability of a Lyapunov function is of great importance for analysis and design in these cases. Moreover, exponential or finite-time and local or global stability are required to be established, since they are not derived from the homogeneity.  相似文献   
997.
The problem of constructing functional observers for linear systems with unknown inputs is considered. Necessary and sufficient conditions for the existence of a proper observer (without differentiations) are revisited. A simple and explicit form of a functional observer is presented. It is shown that when such observer is not proper, it is still possible to use the High-Order Sliding Mode differentiator to implement it. Nevertheless, in such case, additional conditions on the system and the unknown input are required.  相似文献   
998.
Within the framework of numerical modelling and multi-objective control of partial differential equations, in this work we deal with the problem of determining the optimal location of a new industrial plant. We take into account both economic and ecological objectives, and we look not only for the optimal location of the plant but also for the optimal management of its emissions rate. In order to do this, we introduce a mathematical model (a system of nonlinear parabolic partial differential equations) for the numerical simulation of air pollution. Based on this model, we formulate the problem in the field of multi-objective optimal control from a cooperative viewpoint, recalling the standard concept of Pareto-optimal solution, and pointing out the usefulness of Pareto-optimal frontier in the decision making process. Finally, a numerical algorithm – based on a characteristics/Galerkin discretization of the adjoint model – is proposed, and some numerical results for a hypothetical situation in the region of Galicia (NW Spain) are presented.  相似文献   
999.
This paper quantitatively measures technological change in U.S. jet fighter aircraft from 1944 to the present day using the hedonic pricing approach. The technical and performance characteristics of jet fighters have changed dramatically between the time they were first developed at the beginning of the 1940s and the present. Parallel to this technological change there has been a sharp escalation in costs regarding the new generations of jet fighter aircraft. We estimate a measure of price for the performance and technical characteristics of these aircraft. Embodied technological change in jet fighter airframes is measured using quality-adjusted prices. Although the flyaway cost of jet fighter aircraft has soared, on average, by about 12.63% per year, the quality-adjusted aircraft cost has only risen by about 2.6% per year, a figure lower than the average observed general inflation rate for the period (around 4%). This represents an impressive average technological progress ratio of around 10% per year. A revealed preferences argument shows that the characteristic most valued by the government is stealth capability, followed by advanced avionics.  相似文献   
1000.
Emergence of new industries from evolving technologies is critical to the global economy, yet has been relatively understudied due to the paucity of available data. This study draws lessons on industry emergence, by analyzing how a solid-state lighting (SSL) industry grew out of light emitting diode (LED) technologies that evolved for half a century, with participation by tens of thousands of researchers in universities, national laboratories, and firms. Using data on publications, patents, and firms combined with business history we trace the evolution of SSL through a succession of market niches. At times a few researchers with unorthodox research approaches made breakthroughs that greatly advanced particular technology trajectories and pushed LED research in unexpected directions. A succession of LED market niches advanced the technology and provided profits to incentivize continuing research while reducing cost and improving efficacy of LEDs. Innovating firms developed a thicket of patents and captured substantial profit, but were embroiled in extensive litigation that was ultimately resolved through cross-licensing. A major new generation of lighting products is now disrupting the traditional lighting industry. Although the leading incumbent lighting firms all invested early and heavily in SSL, the industry's future leadership is uncertain.  相似文献   
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