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71.
Matthew Davidson Vladimir KhmelkovKyle Baker Thomas Lickona 《International Journal of Educational Research》2011,50(3):190-197
Schools today struggle to prepare students for the moral and performance character challenges they will face in the 21st Century. Whether it is bolstering academic performance, reducing dropout, or improving integrity and safety, developing the character and culture of excellence and ethics is a critical need of schools—and yet they must do so with limited time and money amid a sea of competing priorities and mandates, and without the aid of required curricula, training and coaching. In this article, we describe the Power2Achieve Program, a student-centered, teacher-delivered program for developing the character and culture needed for success in school, work and beyond. We lay out the key theoretical and practical features of the program, describe how it aligns with and enhances other current school improvement pedagogies, and present our research approach for continuous improvement and assessment of impact. 相似文献
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The paper considers planar interception engagements against maneuverable targets using a linearized kinematic model with constant velocities. Both the interceptor and the target have bounded controls and first-order linear dynamics. Due to the linearization, the duration of the interception is prescribed. The target dynamics is fixed, but the interceptor has variable structure dynamics, switching from one mode to another once during the engagement. For such engagements the capture zone of a given linear feedback control is constructed. Numerical examples demonstrate that proper change of the interceptor dynamic mode leads to an enlarged capture zone. 相似文献
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Martin Ebon Lawrence C. Soley John S. Nichols Olive Renier Vladimir Rubinstein Tran Van Dinh 《Communication Booknotes Quarterly》2013,44(5-6):44-45
THE SOVIET PROPAGANDA MACHINE by Martin Ebon (New York: McGraw-Hill, 1987—$22.95) CLANDESTINE RADIO BROADCASTING: A STUDY OF REVOLUTIONARY AND COUNTERREVOLUTIONARY ELECTRONIC COMMUNICATION by Lawrence C. Soley and John S. Nichols (New York: Praeger, 1987—$47.95) ASSIGNED TO LISTEN: THE EVESHAM EXPERIENCE, 1939–43 by Olive Renier and Vladimir Rubinstein (London: BBC External Services, 1986—L3.95, paper, plus 25% more to cover postage and packing outside of the U.K.) INDEPENDENCE, LIBERATION, REVOLUTION: AN APPROACH TO THE UNDERSTANDING OF THE THIRD WORLD by Tran Van Dinh (Norwood, NJ: Ablex, 1987—$37.50) FOLLOWING THE FOOTPRINTS: PROTECTING FILM AND TV RIGHTS IN THE WORLD SATELLITE MARKETPLACE edited by Charles Firestone and Daniel Brenner (Communications Law Program, UCLA School of Law, University of California, Los Angeles 90024—price not given, paper) 相似文献
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Vladimir Macias Israel Becerra Edgar Martinez Rafael Murrieta-Cid Hector M. Becerrra 《Journal of The Franklin Institute》2021,358(9):4761-4792
In this paper, we propose a feedback-based control approach to execute the time optimal motion trajectories for a differential drive robot. These trajectories are composed of straight lines and rotations in place. We show that the evolution of the position of a single landmark over time, in a local reference frame, makes it possible to track a prescribed time-optimal robot’s trajectory, based on feedback of the landmark’s position. We also show that the closed-loop system is an exponentially stable one with a nonvanishing perturbation, and that globally uniformly ultimately boundedness of the tracking errors can be achieved. The two main results of this work are: 1) Our approach leverages visual servo control type of methods with tools from optimal control for executing time-optimal trajectories in the state space based on feedback information. 2) The approach is able to work with the minimum number of landmarks–only one–this represents a necessary and sufficientcondition for landmark-based navigation. Experiments in a physical robot, a nonholonomic differential drive system equipped with an omnidirectional laser sensor, are shown, which validate the proposed theoretical modelling. 相似文献
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