activity
20092021
most citedAverage Shortest Path Length of Graphs of Diameter 3

3 citations · 7 across the 6 of their papers we have counts for

collaborators

8 papers

cs.DM2021

Reversible Random Walks on Dynamic Graphs

Nobutaka Shimizu, Takeharu Shiraga

Recently, random walks on dynamic graphs have been studied because of their adaptivity to the time-varying structure of real-world networks. In general, there is a tremendous gap b…

cs.CC2020★ 1 cited

Nearly Optimal Average-Case Complexity of Counting Bicliques Under SETH

Shuichi Hirahara, Nobutaka Shimizu

In this paper, we seek a natural problem and a natural distribution of instances such that any -time algorithm fails to solve most instances drawn from the distribution…

math.PR2020

How Many Vertices Does a Random Walk Miss in a Network with Moderately Increasing the Number of Vertices?

Shuji Kijima, Nobutaka Shimizu, Takeharu Shiraga

Real networks are often dynamic. In response to it, analyses of algorithms on {\em dynamic networks} attract more and more attentions in network science and engineering. Random wal…

math.PR2020

Quasi-majority Functional Voting on Expander Graphs

Nobutaka Shimizu, Takeharu Shiraga

Consider a distributed graph where each vertex holds one of two distinct opinions. In this paper, we are interested in synchronous voting processes where each vertex updates its op…

math.PR2019

Phase Transitions of Best-of-Two and Best-of-Three on Stochastic Block Models

Nobutaka Shimizu, Takeharu Shiraga

This paper is concerned with voting processes on graphs where each vertex holds one of two different opinions. In particular, we study the \emph{Best-of-two} and the \emph{Best-of-…

cs.DM2016★ 3 cited

Average Shortest Path Length of Graphs of Diameter 3

Nobutaka Shimizu, Ryuhei Mori

A network topology with low average shortest path length (ASPL) provides efficient data transmission while the number of nodes and the number of links incident to each node are oft…

cond-mat.other2009★ 2 cited

Vortex Fluid Relaxation Model for Torsional Oscillation Responses of Solid 4He

Sergey K. Nemirovskii, Nobutaka Shimizu, Yoshinori Yasuta +1

A phenomenological model is developed to explain a new set of detailed torsional oscillator data for hcp 4He. The model is based on Anderson's idea of the vortex fluid (vortex tang…

cond-mat.other2009★ 1 cited

Possible vortex fluid to supersolid transition in solid He below about 75 mK

Nobutaka Shimizu, Yoshinori Yasuta, Minoru Kubota

A detailed torsional oscillator (TO) study on a stable solid 4He sample at 49 bar with To = 0.5K, is reported to T below the dissipation peak at Tp . We find hysteretic behavior st…