This paper proposes a new methodology for coordinating multi-robot teams in the execution of cooperative tasks. It is based on a dynamic role assignment mechanism in which the robots assume and exchange roles during cooperation. We model the role assignment under a hybrid systems framework, using a hybrid automaton to represent roles, transitions and controllers. Using a multi-robot simulator, ...

Helping students in the professions apply conceptual ideas to the problems of practice is a key goal of problem-based learning (PBL). Because PBL is organized around small, collaborative groups, scaling up PBL to large, heterogeneous classes poses significant challenges for implementation. This study presents a hybrid model that mixes online and face-to-face PBL. The STELLAR system was develope...

in this paper we apply hybrid functions of general block-pulse‎ ‎functions and legendre polynomials for solving linear and‎ ‎nonlinear multi-order fractional differential equations (fdes)‎. ‎our approach is based on incorporating operational matrices of‎ ‎fdes with hybrid functions that reduces the fdes problems to‎ ‎the solution of algebraic systems‎. ‎error estimate that verifies a‎ ‎converge...

in this paper, an intelligent control strategy based on combination of the “flatness based control technique” and the “perturbation and observation (p&o;) mppt algorithm” is developed and investigated to control a hybrid electric energy source (heps). this ehps is composed of a fuel cell system (fc) and a solar panel (sp), as the main source and a supercapacitor bank (sc), as the auxiliary sour...

objective(s) the main objective of this study was to investigate the status of chromosome stability in 3 human-mouse hybridoma cell lines over a period of time in various passages. materials and methods metaphase spreads from 3 human-mouse cell lines (hf2x653, spmo-4 and f3b6) that had been cultured in 4 successive passages, from 1 to 4 weeks, were prepared and analyzed. metaphase chromosomes s...

in this work, we report a new well dispersed molybdenum complex attached through the mediation of aminopropylsilyl groups on the surface of multi-walled carbon nanotubes (mwcnts). the prepared hybrid nanomaterial was characterized with different physicochemical methods such as fourier transform infrared and atomic absorption spectroscopies, transmission electron microscopy, energy-dispersive x-...

in most cases, fiber reinforced self-compacting concrete (frscc) contains only one type of fiber. the use of two or more types of fibers in a suitable combination may potentially not only improve the overal properties of self-compacting concrete, but may also result in performance synergie. the combining of fibers, often called hybridization, is investigated in this paper for a cimentetious mat...

In this paper, we introduce the new class of implicit L-stable generalized hybrid methods for the numerical solution of first order initial value problems. We generalize the hybrid methods with utilize ynv directly in the right hand side of classical hybrid methods. The numerical experimentation showed that our method is considerably more efficient compared to well known methods used for the n...

Composite propellers offer high damping characteristics and corrosion resistance when compared with metal propellers. But the design of a hybrid composite propeller with the same strength of metal propeller is the critical task. For this purpose, the present paper focusses on fluid-structure interaction analysis of hybrid composite propeller with Carbon/Epoxy, R-Glass/Epoxy and S2-Glass/Epoxy t...

the hybrid molten/solid in2o3 - 30-48 wt.% bi2o3 oxide materials were studied with respect to their transport properties. the conductivities, oxygen ion transport numbers and oxygen permeation fluxes have been measured by using the four-probe dc, volumetric measurements of the faradaic efficiency and gas flow techniques, respectively. we show that the oxygen permeability of the hybrid molten/so...