8,332 research outputs found

    Experimental Testing Program in Elementary Chemistry: A Preliminary Report

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    An experimental testing program is described which utilizes questions that are partly computer composed, in addition to a section composed by the instructor, and a retesting option to the student. Results from a trial of the program for one term indicate that (1) course grades were improved, (2) the student withdrawal failure rate was unaffected, and (3) the employed students took greater advantage of the retest than did the unemployed students

    The algebraic dichotomy conjecture for infinite domain Constraint Satisfaction Problems

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    We prove that an ω\omega-categorical core structure primitively positively interprets all finite structures with parameters if and only if some stabilizer of its polymorphism clone has a homomorphism to the clone of projections, and that this happens if and only if its polymorphism clone does not contain operations α\alpha, ÎČ\beta, ss satisfying the identity αs(x,y,x,z,y,z)≈ÎČs(y,x,z,x,z,y)\alpha s(x,y,x,z,y,z) \approx \beta s(y,x,z,x,z,y). This establishes an algebraic criterion equivalent to the conjectured borderline between P and NP-complete CSPs over reducts of finitely bounded homogenous structures, and accomplishes one of the steps of a proposed strategy for reducing the infinite domain CSP dichotomy conjecture to the finite case. Our theorem is also of independent mathematical interest, characterizing a topological property of any ω\omega-categorical core structure (the existence of a continuous homomorphism of a stabilizer of its polymorphism clone to the projections) in purely algebraic terms (the failure of an identity as above).Comment: 15 page

    Analytical modeling of helicopter static and dynamic induced velocity in GRASP

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    The methodology used by the General Rotorcraft Aeromechanical Stability Program (GRASP) to model the characteristics of the flow through a helicopter rotor in hovering or axial flight is described. Since the induced flow plays a significant role in determining the aeroelastic properties of rotorcraft, the computation of the induced flow is an important aspect of the program. Because of the combined finite-element/multibody methodology used as the basis for GRASP, the implementation of induced velocity calculations presented an unusual challenge to the developers. To preserve the modelling flexibility and generality of the code, it was necessary to depart from the traditional methods of computing the induced velocity. This is accomplished by calculating the actuator disc contributions to the rotor loads in a separate element called the air mass element, and then performing the calculations of the aerodynamic forces on individual blade elements within the aeroelastic beam element

    MATH 1115

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    Variability of crop calendar stage dates

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    There are no author-identified significant results in this report

    Caught in the Middle: Chat(ting) about Black School Leaders

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    The purpose of this article is to “chat” about my experience using Eurocentric theories in racial and culturally centered qualitative inquiry. The challenge I face is that I believe researchers can use Eurocentric theories to conceptualize ‘appropriate’ frameworks to conduct rigorous culturally responsible and sensitive research that contributes to existing scholarly dialogue and empirical literature on culturally sensitive designs in the field of qualitative research. In this paper I use my research experience to address the question, “How can researcher(s) conduct culturally responsible and sensitive research?” I use autoethnography and writing as a method of inquiry to (re)present the multi-layers of within and in-between chats while being caught in the middle. Chat metaphorically represents introspective musings, scholarly dialoguing, analyzing, interpreting, (re)presenting and defending. I use Tillman’s (2002) culturally sensitive research frame as an analytic tool to critically analyze my research design. I argue that qualitative researchers of ethnic, racial and cultural communities can conceptualize appropriate frameworks from mainstream theories to conduct culturally responsible and sensitive research that can help transform the traditional knowledge of fields in education, educational leadership, urban education, and policy
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