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721.
Allison Gruner Gandhi Rachel Slama So Jung Park Patrick Russo Kendra Winner Robin Bzura 《Journal of research on educational effectiveness》2018,11(2):240-266
We used a comparative interrupted time series design to examine the impact of the Massachusetts' Wraparound Zone Initiative on student achievement, attendance, retention, and suspension. This initiative was designed to create coordinated district systems that allow schools to proactively and systematically address students' nonacademic needs. The state education agency awarded grants to seven high-need districts, each of which used the funds to support a select group of schools in implementing strategies that focused on school climate and culture, family engagement, systems to identify and address student needs, and community partnerships. Results from this study showed that students in Wraparound Zone schools performed better on state academic assessments than students in comparison schools, when considering prior achievement trends. Effects were statistically significant in the 3rd year of implementation. The impact on academic achievement was greatest for third- and fourth-grade students, and was particularly strong for English learners. There was no statistically significant overall impact on attendance, retention, or suspension. 相似文献
722.
Recently, a polynomials-based integral inequality was proposed by extending the Moon’s inequality into a generic formulation. By imposing certain structures on the slack matrices of this integral inequality, this paper proposes an orthogonal-polynomials-based integral inequality which has lower computational burden than the polynomials-based integral inequality while maintaining the same conservatism. Further, this paper provides notes on relations among recent general integral inequalities constructed with arbitrary degree polynomials. In these notes, it is shown that the proposed integral inequality is superior to the Bessel–Legendre (B–L) inequality and the polynomials-based integral inequality in terms of the conservatism and computational burden, respectively. Moreover, the effectiveness of the proposed method is demonstrated by an illustrative example of stability analysis for systems with additive time-varying delays. 相似文献
723.
Pak Kin Wong Xiang Hui Gao Ka In Wong Chi Man Vong 《Journal of The Franklin Institute》2018,355(4):1517-1538
Modern engines are controlled by electronic control units, which operate all the engine actuators based on the signals from various sensors in the engine. Traditionally, the control parameters of the actuators are obtained through huge amount of trial-and-error experiments. However, using traditional approach to calibrate these parameters becomes more challenging with the increasing incorporation of new technologies into advanced engines. In order to reduce the number of experiments required in the calibration process of modern engines, a novel point-by-point engine calibration approach based on machine learning methods is proposed in this study. It is an iterative procedure that, for a given operating point, sequential design of experiment (DoE) strategy is utilized to measure the responses of different engine sensors corresponding to different actuator signals, and a machine learning algorithm called initial-training-free online extreme learning machine is utilized to incrementally learn the relationship between the sensors and actuators based on the measurement acquired. In each iterative cycle, meta-heuristic optimization is performed on the machine-learning-based model to search for the best parameters, which are then used as the initial parameters for generating DoE plan of the next cycle. The iteration is repeated until the optimal parameters of that operating point are found. To verify the effectiveness of the proposed approach, experiments on both simulation engine in commercial software and real engine in test bench have been conducted. The results show that the engine calibration can be carried out with significant fewer experiments and time by using the proposed approach. 相似文献
724.
Xiangyong Chen Jinde Cao Ju H. Park Tingwen Huang Jianlong Qiu 《Journal of The Franklin Institute》2018,355(5):2892-2911
By considering network transmission mode, this paper addresses the finite-time multi-switching synchronization problem for two kinds of multiple chaotic systems. For multiple same-order chaotic systems, we construct the general switching rules and analyze the existence of switching cases. The presented schemes guarantee the states of each derive system to be finite-timely synchronized with the desired states of every respond system in the different transmission paths and switching sequences. For multiple different order chaotic systems, we analyze a special multi-switching hybrid synchronization behavior, where part of the states are completely synchronized and the others belong to combination synchronization. Moveover, the easily verifiable criterion is derived for such synchronization. Finally, numerical examples are given to show the effectiveness of the presented theoretical results. 相似文献
725.
726.
Rebecca L. Brower Chenoa S. Woods Tamara Bertrand Jones Toby J. Park Shouping Hu David A. Tandberg 《Community College Journal of Research & Practice》2018,42(2):112-128
The purpose of this qualitative study is to understand how educational scaffolding may explain changing patterns of student success in mathematics in the era of developmental education (DE or remediation) reform in Florida College System (FCS) institutions. Specifically, we apply the concept of scaffolding to underprepared FCS students who are at risk of dropping out or failing gateway courses (the first credit-bearing college-level class in a course sequence) because they lack the academic skills necessary to succeed in college-level coursework, particularly in mathematics. We present data from focus groups conducted at 10 FCS institutions, suggesting that a reduction of scaffolding in math remediation occurred in the areas of course sequencing, instruction, and coordination with academic support services following state-level policy changes. In light of these findings, we offer a discussion of practical recommendations for college administrators related to academic advising, instructional strategies in DE courses, coordination between developmental and college-level instructors, student success courses, and the integration of DE instruction with academic support. We also suggest directions for continued research on the effects of policy changes in the FCS and DE reform efforts across the country. 相似文献