Naval Postgraduate School

About: Naval Postgraduate School is a education organization based out in Monterey, California, United States. It is known for research contribution in the topics: Tropical cyclone & Boundary layer. The organization has 5246 authors who have published 11614 publications receiving 298300 citations. The organization is also known as: NPS & U.S. Naval Postgraduate School.

Tree Generating Regular Systems

Abstract: Trees are defined as mappings from tree structures (in the graph-theoretic sense) into sets of symbols. Regular systems are defined in which the production rules are of the form Φ → ψ , where Φ and ψ are trees. An application of a rule involves replacing a subtree Φ by the tree ψ . The main result is that the sets of trees generated by regular systems are exactly those that are accepted by tree automata. This generalizes a theorem of BUchi, proved for strings.

Effect of the dynamic interaction on coordinated control of mobile manipulators

Abstract: A mobile manipulator composed of a manipulator and a mobile platform has a much larger workspace than a fixed-base manipulator due to the mobility provided by the platform. While the on-board manipulator reaches out and performs manipulation tasks, the role of the mobile platform is to position the manipulator in a preferred configuration. In this paper, we study the effect of the dynamic interaction between the manipulator and the mobile platform of a mobile manipulator on the task performance. We consider the task that the end point of the manipulator tracks a desired trajectory in a fixed reference frame. The effect of the dynamic interaction on the tracking performance is examined by comparing four different cases: 1) with full compensation of the dynamic interaction with each other; 2) with the mobile platform compensating the dynamic interaction caused by the manipulator; 3) with the manipulator compensating the dynamic interaction caused by the mobile platform; and 4) without any compensation of the dynamic interaction at all. Simulation results from representative trajectories are presented to illustrate the effect.

Extratropical Transition of Western North Pacific Tropical Cyclones: An Overview and Conceptual Model of the Transformation Stage

Abstract: Extratropical transition (ET) in the western North Pacific is defined here in terms of two stages: transformation, in which the tropical cyclone evolves into a baroclinic storm; and reintensification, where the transformed storm then deepens as an extratropical cyclone. In this study, 30 ET cases occurring during 1 June–31 October 1994–98 are reviewed using Navy Operational Global Atmospheric Prediction System analyses; hourly geostationary visible, infrared, and water vapor imagery; and microwave imagery. A brief climatology based on these cases is presented for the transformation stage and the subsequent cyclone characteristics of the reintensification stage. A three-dimensional conceptual model of the transformation stage of ET in the western North Pacific Ocean is proposed that describes how virtually all 30 cases evolved into an incipient, baroclinic low. The three-step evolution of the transformation of Typhoon (TY) David (September 1997) is described as a prototypical example. Four importa...

Great Principles of Computing

Abstract: The great principles of computing have been interred beneath layers of technology in our understanding and our teaching. It is time to set them free.