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 & Nonlinear system. 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.

Issues in the development of a requirements traceability model

Abstract: In the development of large-scale, real-time, complex computer intensive systems, it is essential to maintain traceability of requirements to various outputs to ensure that the system meets the current set of requirements. Based on an empirical study in a simulated systems development environment, several major issues that need to be considered in the development of a model of requirements traceability are addressed. >

The Presidents' Day Cyclone of 18–19 February 1979: Synoptic Overview and Analysis of the Subtropical Jet Streak Influencing the Pre-Cyclogenetic Period

Abstract: A detailed examination is undertaken of the subtropical jet (STJ) streak revealed by an analysis of the Presidents' Day cyclone of February 18-19, 1979. During its 24 h period, the STJ's flow became increasingly supergeostrophic and apparently unbalanced, while ageostrophic wind speeds increased to more than 30 m/sec in association with a significant cross-contour component, directed toward lower values of the Montgomery streamfunction, as the flow along the STJ became more divergent with time. These phenomena are linked to the increasing confluence in the entrance region of the jet streak and the decreasing wavelength of the trough-ridge system in which the jet streak was embedded. The upper level divergence and upward vertical motion near the axis of the STJ are found to be important factors in the development of the cyclone's first area of heavy snow.

An improved quaternion-based Kalman filter for real-time tracking of rigid body orientation

Abstract: This paper presents an improved Kalman filter for real-time tracking of human body motions. An earlier version of the filter was presented at IROS 2001. Since then, the filter has been substantially improved. Real-time tracking of rigid body orientation is accomplished using the MARG (magnetic, angular rate, and gravity) sensors. A MARG sensor measures the three-dimensional local magnetic field, three-dimensional angular rate, and three-dimensional acceleration. A Kalman filter is designed to process measurements provided by the MARG sensors, and to produce real-time orientation represented in quaternions. There are many design decisions as related to choice of state vectors, output equations, process model, etc. The filter design presented in this paper utilizes the Gauss-Newton method for parameter optimization in conjunction with Kalman filtering. The use of the Gauss-Newton method, particularly the reduced-order implementation introduced in the paper, significantly simplifies the Kalman filter design, and reduces computational requirements.

Endogenous formation of coalitions

Abstract: We develop a model of coalition formation based on personal proximities among the players of an n-person game. Several examples are worked out in detail, showing that certain coalitions are much more stable than others, and/or much more likely to form than others. We also consider the dynamics of such coalition-formation. By a numerical example, we show that small changes in the initial conditions can lead to very different results in the coalitions formed in a given game.

A Geometrically Nonlinear Theory of Elastic Plates

Abstract: A set of kinematical and intrinsic equilibrium equations are derived for plates undergoing large deflection and rotation but with small strain