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A Qualitative Study of Parental Empowerment and Satisfaction Following IEP Meetings
No full textThis qualitative narrative inquiry study examined how parents of children receiving special education services experienced empowerment during the Individualized Education Program (IEP) process and how these experiences related to parental satisfaction. Guided by empowerment theory, semi-structured interviews were conducted with four parents to explore the roles of participation, control, and critical awareness. Findings indicated that empowerment did not stem from the IEP system itself; rather, parents developed empowerment through their own persistence, questioning, and reflection as they navigated unclear procedures and inconsistent communication. While one participant described a collaborative process, others reported feeling excluded or presented with predetermined decisions. Parents with greater educational or professional backgrounds demonstrated higher critical awareness, contributing to differing levels of empowerment. Overall satisfaction was closely tied to how included, informed, and influential parents felt. Results underscored the need for schools and school-based teams to adopt transparent, culturally responsive practices that promote equitable parent participation
A Correlated Many-Electron Approach to Singlet Fission
No full textπ−conjugated organic systems present numerous opportunities for exploration of fundamental physics due to the prevalent role of electron correlations in the optoelectronic properties of these systems, as well as potentially being useful for many technological applications. In particular, they may serve as strong candidates for harnessing singlet fission (SF), a spin-allowed photophysical process in which a single incident photon excites the material to the dipole-allowed spin singlet state which then undergoes internal conversion to a pair of triplet excitons bound into a state of total spin 0. These triplets may in principle then dissociate and each contribute an electron-hole (e-h) pair to the resulting photocurrent that can be used in
a solar cell, thereby doubling the output of charge carriers generated upon initial photoexcitation in comparison with traditional technologies. Thus, SF represents one possible avenue for surpassing current fundamental solar cell efficiency limits and poses significant promise for addressing outstanding challenges in renewable energy. Complete description and understanding of SF relies on characterization of the triplet pair intermediate state, an inherently multiparticle excited state, as well as potentially charge transfer (CT) states that have been theorized to mediate the SF process. From a theoretical perspective, this requires the use of correlated electronic structure models to properly capture the quantum many-body nature of these excited states. We present results of such calculations based on multireference configuration interaction (CI) techniques applied to the many-body Pariser-Parr-Pople (PPP) model for a series of SF candidate systems based on dimers of acene monomers linked by bridge molecules. Through comprehensive analysis of the excited states relevant for SF and linear and transient absorption spectra, we develop a theory of triplet pair generation in these compounds and present conclusive evidence that this process is mediated by CT states whose specific form depends sensitively on seemingly minute changes to the molecular structures. Comparison of the calculated ground and excited state absorption spectra with experimental results based on transient absorption (TA) spectroscopy enables direct mapping of the calculated optoelectronic properties of these compounds to measured SF dynamics such as the time to generate the triplet pair. Our results thus establish the central role of CT in the SF process and may inform future searches for potential SF candidate systems
31 - devotional
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
25 - anyone who does not know love is still in death
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
19 - for places we’ve never been but dream of going once we die
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
17 - When people ask what I am instead of who
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
16 - Crystal Stair
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
04 - black body as [ ] bird
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
02 - The Valley of the Latte
No full textDanielle P. Williams reading poems from Chamorrita SongThese recordings are made available by the University of Arizona Press and University of Arizona Libraries. If you have questions about this title, please contact the UA Press at http://www.uapress.arizona.edu/
A New Algorithm for the Open-Pit Production Scheduling Optimization Problem
No full textOpen-pit mine production scheduling optimization is pivotal in ensuring a mine operates profitably. However, achieving optimality in a production schedule is often intractable. This is due to two factors. The first is the NP-hard classification of the problem, meaning there are no known efficient algorithms for finding exact solutions. The second is the large scale of realistic block models, which can lead to millions of variables and constraints with which the optimization problem is subject to. Therefore, it is common practice to rely on heuristics and block aggregation methods for generating operationally feasible solutions. However, these solutions are not guaranteed to be optimal and are more often than not far from optimality. This research presents an alternative for gathering optimal and near-optimal solutions through a novel relaxation-repair algorithm. Precedence constraints, which make up the majority of the constraints present in an open-pit production scheduling optimization problem, represent open-pit slope stability. However, due to how they are enforced, each is implied by the other precedence constraints when the full precedence set is considered. Because of this, the constraint matrix size is inflated, and the solver’s performance decreases. The goal of this research is to showcase a method for applying only subsets of precedence constraints instead of the full precedence set. The initial relaxation phase of the algorithm solves, to optimality, the problem with only a subset of the precedence constraints. However, the relaxation is not assured to be operationally feasible with respect to the full precedence set. Therefore, a final repair phase is conducted to recover feasibility. Some instances were able to achieve optimality without requiring a repair step. Through testing, this algorithm has shown that it can outperform a traditional precedence formulation in several instances. In some cases, the algorithm generated optimal and near-optimal (<0.15% optimality gap) production schedules in under a quarter of the time