A three-dimensional backward-wave network matched with free space

A backward-wave slab based on a capacitively and inductively loaded three-dimensional transmission-line network is designed in such a way that impedance-matching with free space is obtained. To enable field propagation from free space to the network and vice versa, the use of a transition layer is proposed. Matching of the designed network with free space and negative refraction occurring at the slab interfaces are confirmed with full-wave simulations.Comment: 8 pages, 5 figure

Drifting Pattern Domains in a Reaction-Diffusion System with Nonlocal Coupling

Drifting pattern domains (DPDs), moving localized patches of traveling waves embedded in a stationary (Turing) pattern background and vice versa, are observed in simulations of a reaction-diffusion model with nonlocal coupling. Within this model, a region of bistability between Turing patterns and traveling waves arises from a codimension-2 Turing-wave bifurcation (TWB). DPDs are found within that region in a substantial distance from the TWB. We investigated the dynamics of single interfaces between Turing and wave patterns. It is found that DPDs exist due to a locking of the interface velocities, which is imposed by the absence of space-time defects near these interfaces.Comment: 4 pages, 4 figure

Human Body–Electrode Interfaces for Wide-Frequency Sensing and Communication: A Review

Several on-body sensing and communication applications use electrodes in contact with the human body. Body–electrode interfaces in these cases act as a transducer, converting ionic current in the body to electronic current in the sensing and communication circuits and vice versa. An ideal body–electrode interface should have the characteristics of an electrical short, i.e., the transfer of ionic currents and electronic currents across the interface should happen without any hindrance. However, practical body–electrode interfaces often have definite impedances and potentials that hinder the free flow of currents, affecting the application’s performance. Minimizing the impact of body–electrode interfaces on the application’s performance requires one to understand the physics of such interfaces, how it distorts the signals passing through it, and how the interface-induced signal degradations affect the applications. Our work deals with reviewing these elements in the context of biopotential sensing and human body communication

A solution concentration dependent transition from self-stratification to lateral phase separation in spin-cast PS:d-PMMA thin films

Thin films with a rich variety of different nano-scale morphologies have been produced by spin casting solutions of various concentrations of PS:d-PMMA blends from toluene solutions. During the spin casting process specular reflectivity and off-specular scattering data were recorded and ex situ optical and atomic force microscopy, neutron reflectivity and ellipsometry have all been used to characterise the film morphologies. We show that it is possible to selectively control the film morphology by altering the solution concentration used. Low polymer concentration solutions favour the formation of flat in-plane phase-separated bi-layers, with a d-PMMA-rich layer underneath a PS-rich layer. At intermediate concentrations the films formed consist of an in-plane phase-separated bi-layer with an undulating interface and also have some secondary phase-separated pockets rich in d-PMMA in the PS-rich layer and vice versa. Using high concentration solutions results in laterally phase-separated regions with sharp interfaces. As with the intermediate concentrations, secondary phase separation was also observed, especially at the top surface

AgRISTARS: Yield model development/soil moisture. Interface control document

The interactions and support functions required between the crop Yield Model Development (YMD) Project and Soil Moisture (SM) Project are defined. The requirements for YMD support of SM and vice-versa are outlined. Specific tasks in support of these interfaces are defined for development of support functions

Embedding the Remote Application Control: Visual API for PDA Programming

PDAs are more and more used as advanced adaptive HEI (human-environment interaction) interfaces, thus enabling their users to easily operate applications remotely running in pervasive computing scenarios. Based on a previous implementation, in this paper we discuss the development of a new set of .NET-compliant Application Programming Interfaces to be used within the Visual Studio IDE. Our main goal is to provide programmers with a set of components to be used with the common drag-and-drop operation, in order to embed a remote application control within an application running on the PDA and vice-versa. The interaction relies on ad-hoc communication protocols over a framework devoted to pair PDAs and remote devices according to their relative position, with no need to use any connection software