EVOLUTION OF HIGH-ORDER NONLINEAR PROPERTY USING SPATIAL DEVELOPING NONLINEAR SCHRODINGER EQUATION IN INTERMEDIATE WATER

In the last two decades, the extreme wave occurrence, its understanding and prediction in deep water become getting clear. However, there are a few studies about the extreme wave occurrence in intermediate water. The authors reported that the appropriate higher-order nonlinear correction is essential to estimate the extreme wave occurrence using the standard Boussinesq equation. Therefore, the other numerical tool such as nonlinear Schrodinger equation (NLS) will be required from the point of view of the direct extreme wave modeling in intermediate water. The purpose of this study is to investigate the evolution of the high-order nonlinear property in intermediate water using the spatial developing nonlinear Schrodinger equation (SD-NLS) for the deep-water generating extreme wave modeling.

Cooperative Loitering Munition Swarm Online Patrolling Route Planning with Nonlinear Seeker Measurement

With the development of autonomous systems, the operational use of loitering munition is shifting from the following of a preplanned fixed route without communication to smart decision-making and collaborative cooperation with sharing information. In this paper, we study the autonomous decision-making and cooperative control strategy of online patrolling for a swarm of loitering munitions using communication to coordinate their route based on maximizing the information they gathered in the operation region. Taking the non-Gaussian nonlinear property of airborne radar seeker into account, we utilized a particle filter-based method to evaluate or to predict the information quality of each action candidate. We also implemented a coordinate descent scheme to enable a distributed and scalable swarm decision-making. Simulation results show that the proposed method provides a better estimation than baselines without the need for external or centralized decision agent.

Sliding Mode Control of Bi-directional DC/DC Converter in DC Microgrid Based on Exact Feedback Linearization

The nonlinear property of bi-directional DC/DC converter in DC Microgrid will cause large voltage disturbance. To solve the above problems, a exact feedback linearization method based on nonlinear differential geometry theory is proposed to realize the linearization of the converter. Moreover, considering the approaching speed of the linearized Bruno standard model, a sliding mode controller is designed by using the exponential approach law. The simulation results show that the method has fast response speed, strong antiinterference ability and good steady-state characteristics.

CHARACTERIZATION OF RUNNING-IN ATTRACTORS RECONSTRUCTED FROM FRICTION SIGNALS

Friction tests were conducted by sliding a ring against a disc under oil lubricated condition. The running-in attractor was generated from measured friction force, vibration and noise signals. On the basis of correlation dimension, predictability was introduced from chaos theory to characterize the running-in attractor. Two parameters, i.e. enclosing radius and average distance were proposed innovatively. The algorithms for the proposed parameters were given as well. Correlation dimension, predictability, enclosing radius and average distance were used to describe the complexity, randomness, bound and convergence degree of a running-in attractor, respectively. This study provides new parameters to quantify the running-in attractor and is meaningful for revealing the nonlinear property of the attractor.

Non-Linear Cellular Dielectrophoretic Behavior Characterization Using Dielectrophoretic Tweezers-Based Force Spectroscopy inside a Microfluidic Device

Characterization of cellular dielectrophoretic (DEP) behaviors, when cells are exposed to an alternating current (AC) electric field of varying frequency, is fundamentally important to many applications using dielectrophoresis. However, to date, that characterization has been performed with monotonically increasing or decreasing frequency, not with successive increases and decreases, even though cells might behave differently with those frequency modulations due to the nonlinear cellular electrodynamic responses reported in previous works. In this report, we present a method to trace the behaviors of numerous cells simultaneously at the single-cell level in a simple, robust manner using dielectrophoretic tweezers-based force spectroscopy. Using this method, the behaviors of more than 150 cells were traced in a single environment at the same time, while a modulated DEP force acted upon them, resulting in characterization of nonlinear DEP cellular behaviors and generation of different cross-over frequencies in living cells by modulating the DEP force. This study demonstrated that living cells can have non-linear di-polarized responses depending on the modulation direction of the applied frequency as well as providing a simple and reliable platform from which to measure a cellular cross-over frequency and characterize its nonlinear property.