Hydrogen diffusion on metals exhibits rich quantum behavior, which is not yet fully understood. Using simulations, we show that many hydrogen diffusion barriers can be categorized into those with parabolic tops and those with broad tops. With parabolic-top barriers, hydrogen diffusion evolves gradually from classical hopping, to shallow tunneling, to deep tunneling as the temperature (T) decrea...

Abstract Electrical properties of beryllium-alumino-tellurite glasses and glass–ceramics doped with iron ions were studied using impedance spectroscopy. The conductivity was measured over a wide frequency range from 10 mHz to 1 MHz the temperature 213 473 K. D.C. values showed correlation Fe-ion concentration ratio on different valence states in samples. On basis Jonscher universal dielectric r...

Port hopping is a typical proactive cyber defense technology, which hides the service identity and confuses attackers during reconnaissance by constantly altering service ports. Although several kinds of port hopping mechanisms have been proposed and implemented, but it is still unknown how effective port hopping is and under what circumstances it is a viable moving target defense because the e...

This review article deals with the ionic conductivity of solid-state electrolytes for lithium batteries. It has discussed mechanisms ion conduction in ceramics, polymers, and ceramic-polymer composite electrolytes. In ceramic electrolytes, transport is accomplished mobile point defects a crystal. Li+ ions migrate mainly via vacancy mechanism, interstitial or interstitial-substitutional exchange...

In this paper, we address the problem of designing time hopping codes for impulse radio multiple access communication systems. Time hopping techniques are first reviewed, including a new code that we proposed [2] for time hopping, and performance in terms of cyclic correlation properties are given. Advantages and disadvantages of different time hopping codes in terms of resource assignment for ...

Photosynthetic reaction centers (PRCs) employ multiple-step tunneling (hopping) to separate electrons and holes that ultimately drive the chemistry required for metabolism. We recently developed hopping maps that can be used to interpret the rates and energetics of electron/hole hopping in three-site (donor-intermediate-acceptor) tunneling reactions, including those in PRCs. Here we analyze sev...

In this paper a detailed explanation of our newly proposed frequency hopped spread spectrum system named “MMFSK-EOD System Using Binary Hopping Pattern” (8) is presented. First, to make clear the concept of FH/M-ary Multilevel FSK modulation (abb. FH/ MMFSK or MMFSK), the waveform and the spectrum differences between MFSK and FH/MFSK or FH/MMFSK are reviewed. Next, to understand the error propa...