Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Turbulence. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

How to Prove Impossibility Under Global Fairness: On Space Complexity of Self-Stabilizing Leader Election on a Population Protocol Model

Abstract: A population protocol is one of distributed computing models for passively-mobile systems, where a number of agents change their states by pairwise interactions between two agents. In this paper, we investigate the solvability of the self-stabilizing leader election in population protocols without any kind of oracles. We identify the necessary and sufficient conditions to solve the self-stabilizing leader election in population protocols from the aspects of local memory complexity and fairness assumptions. This paper shows that under the assumption of global fairness, no protocol using only n−1 states can solve the self-stabilizing leader election in complete interaction graphs, where n is the number of agents in the system. To prove this impossibility, we introduce a novel proof technique, called closed-set argument. In addition, we propose a self-stabilizing leader election protocol using n states that works even under the unfairness assumption. This protocol requires the exact knowledge about the number of agents in the system. We also show that such knowledge is necessary to construct any self-stabilizing leader election protocol.

Proton Conduction and Pore Structure in Sol−Gel Glasses

Abstract: Proton conduction in sol−gel-derived porous glasses was investigated and is related to the pore structure. The porous P2O5−SiO2 glasses absorb water under ambient conditions and consequently increase the electrical conductivity. In glasses having pores ∼5 nm or smaller, the water molecules diffuse through the pores and totally fill the pores. The motion of the water molecules is restricted in small pores, and the absorbed water molecules are well retained even at low humidity. The conductivity of this glass was high in the temperature range down to −20 °C. On the other hand, in glasses with large pores, no confinement effect occurred for the water molecules and the conductivity suddenly decreased below 0 °C.