A bilateral control system connected by a communication network is investigated in this research. A rigid arm is employed as a master arm. A flexible arm is employed as a slave arm and is modeled by a nonlinear system. Moreover, the slave arm collides with an obstacle during its motion. The communication network causes a random delay. Hence, signals become noisy due to this delay. An extended Kalman filter is designed to reduce the effect of the random delay. Numerical simulations are demonstrated to confirm the performance of the proposed system.
In this study, we propose a simple probability density function (PDF) model of Gaussian-Laplacian mixture (GLM) type, which provides a concise parameterization of heavy-tailed data. We construct our model as convex combination of Gaussian and Laplacian PDFs to obtain a minimal parameterization of heavy-tailed data. We then conduct least-squares fitting of our model to a heavy-tailed data generated by a random Duffing oscillator and obtain over 94% of residual sum of squares (RSS) fitness. The resulting model is applied to predicting transient moment responses and achieves over 90% of RSS fitness to Monte–Carlo simulation results of the original system.
In this study, we propose a novel multimodal optimization algorithm, gravitational particle swarm algorithm (GPSA), by replacing the global feedback term of a classical particle swarm optimization with a term that introduces inverse-square gravitational force between particles. We analyze the search behavior of these particles by Monte-Carlo simulation, demonstrating that the particles often gather around the global optima but seldom scatter away from them. Furthermore, our GPSA’s performance is evaluated on benchmark functions, showing that it found over 95.5% and 78.2% of the global optima over the course of multiple runs for two- and three-dimensional benchmark functions, respectively. At the same time, it found all global optima at least 62% and 5% of the separate runs, whereas the existing methods almost entirely failed to do.
This paper addresses the first step to investigate the bifurcation phenomena observed in the current-controlled DC-DC converter with thermoelectric module, and therefore we propose a simple interrupted dynamical system which simulates dynamic behavior of the DC-DC converter with thermoelectric module in nature. The dynamic behavior of the proposed system can be described by one dimensional topology, and therefore, we can define the return map. By using the return map, the rigorous bifurcation analysis can be possible. Because the proposed system simulates dynamic behavior of the converter, the clarified circuit fundamental characteristics are applicable to the converters in nature.
First, we show an interrupted electric circuit with state dependent input that simulates the switching operation of a current-controlled DC-DC converter with a thermoelectric power generation module as a power supply. Next, we define the return map for analyzing bifurcation phenomena observed in the circuit. Finally, the bifurcation phenomena occurring in the circuit are observed using the return map, and the qualitative properties of this circuit are clarified.
5th Generation (5G) mobile communication technology plays the role of a typhoon-eye among world economic superpowers. In a whirlwind of international cutthroat competition, Global Navigation Satellite System (GNSS) precise positioning is said to be the first application of 5G mobile communication services. 5G brings super-low latency and super-large capacity for data transmission. In this situation, we design a new GNSS PPP-RTK assistance system using these 5G exellences, based upon the heritage of precise positioning techniques utilizing Quasi-Zenith Satellite System (QZSS). In the comparison to the existing system, this design makes the horizontal accuracy from several centimeters to almost one centimeter, and makes the convergence time from one minute to a few seconds. These are the highest performances as the unidirectional assistance of real-time GNSS positioning for mass-market applications which should be implemented into the smart society which we have been actively building today.