論文 / 著書情報
Article / Book Information
題目(和文)
Title(English)

Vulnerability of Transportation Networks to Cascading Failure

著者(和文)

杉下佳辰

Author(English)

Kashin Sugishita

出典(和文)

学位:博士(工学),学位授与機関:東京工業大学,
報告番号:甲第11168号,
授与年月日:2019年3月26日,
学位の種別:課程博士,
審査員:朝倉 康夫,屋井 鉄雄,室町 泰徳,福田 大輔,花岡 伸也

Citation(English)

Degree:Doctor (Engineering),Conferring organization: Tokyo Institute of Technology,
Report number:甲第11168号,
Conferred date:2019/3/26,
Degree Type:Course doctor,
Examiner:,,,,

学位種別(和文)

博士論文

Category(English)

Doctoral Thesis

種別(和文)

要約

Type(English)

OutlinePowered by T2R2 (Tokyo Institute Research Repository)

T OKYO I NSTITUTE OF T ECHNOLOGYD OCTORAL T HESIS

Vulnerability of Transportation Networksto Cascading Failure

Author:Kashin S UGISHITA

Supervisor:
Prof. Yasuo A SAKURA

A thesis submitted in fulfillment of the requirements
for the degree of Doctor of Engineeringin theDepartment of Civil and Environmental Engineering

February 19, 2019

iii

TOKYO INSTITUTE OF TECHNOLOGY

Abstract
School of Environment and Society
Department of Civil and Environmental Engineering
Doctor of Engineering
Vulnerability of Transportation Networks to Cascading Failure
by Kashin S UGISHITAThis dissertation, titled Vulnerability of Transportation Networks to Cascading
Failure, consists of the following six chapters.
Chapter 1 describes the introduction. Complex networked systems sometimes collapse caused by localized errors. Such a phenomenon is called cascading failure and it has been studied in complex networks. Most existingstudies have discussed blackouts or communication disturbances and there
are some successes in engineering applications such as expressing patterns
of failure propagation in the Italian blackout in 2003. ? shows the naturesof the systems where cascading failure occur and takes power grids or communication systems as examples. However, not only these systems but alsotransportation systems should satisfy these natures. Nevertheless, there has
been little mentions about transportation systems so far. This situation seems
strange, because complex networks should be a study of any complex networked systems in the real world. Two fields have network vulnerability
as a research topic in common. Therefore it is expected that both academic
fields will develop further by interdisciplinary fusion of concepts in different fields. In order to achieve this great objective, this dissertation aims toobjectively and comprehensively clarify the overall picture of the studies on
network vulnerability in the two fields, to investigate cascading failure andpropose risk management, and to discuss the possibility of interdisciplinary
integration of concepts and the future directions.
Chapter 2 proposes a framework for analyzing a citation network withsome community structures and applies to the vulnerability studies in thefields of transportation and complex networks. We objectively and comprehensively clarify the overall picture of the studies on network vulnerability
in the two fields. First of all, the publication records are obtained from the online academic database Web of Science. Then a citation network where nodes
and directed links represent the publications and the citation relations respectively is constructed. Next, the giant weakly connected component (GWCC)
is extracted and analyzed. As the first step of the analysis of GWCC, thecommunity structure is revealed by applying the Louvain algorithm. Then,the major research development in each community is clarified by applying
the main path analysis and papers are reviewed. Finally, the citation patterns
among different communities are visualized with a Sankey diagram. We qu-iv
antitatively reveal the asymmetric citation patterns between the two fields.
We also show that there is little citation relationships between communities
of cascading failure and transport network vulnerability.
Chapter 3 investigates cascading failure in complex networks. We show
the attack tolerance of homo/heterogeneous networks and propose a novel
risk management to protect networked systems from cascading failure. The
proposed method utilizes an index called collective-influence which has been
applicable for identifying influencers or prevention of epidemic diffusion insocial networks. Differently from previous studies, we identify non-influencers
and intentionally remove them right after initial failure to prevent propagation of failures. Comparing the existing strategy proposed by ?, we showthat the proposed strategy can mitigate damage more effectively, especiallyfor heterogeneous networks, with much less computational cost.
Chapter 4 investigates cascading failure in transportation networks. We
show gridlock as cascading failure in transportation networks and propose
a risk management of intentionally removing links (link closures), which isinspired by the risk management in Chapter 3. Gridlock, a state of zerothroughput, corresponds to the eventual state in the process of cascading
failure. Namely, when a limited event eventually brings about gridlock, theentire process can be captured as cascading failure. We analyze the influencesof route choice behavior, which is considered important in traffic control, on
the propagation of failures. The obtained results imply that the slight difference of the network topology has big influences and it sometimes helps toavoid gridlock naturally but it can also accelerate cascading failure and gridlock state can be achieved much faster. Furthermore, we show that the routechoice behavior strongly influences the effect of the risk management.
Chapter 5, based on the results obtained in the previous chapters, discusses the interdisciplinary fusion of concepts qualitatively and also discusses
the future direction. First of all, with regard to chapter 2, we show that static
analysis methods in complex networks have been mainly applied to transportation networks. Also we show that edge betweenness centrality in complex networks has been extended in considering with the dynamic aspects ofpublic transportation networks. Next, based on the results obtained in chapters 3 and 4, it is pointed out that the vulnerability of heterogeneous networks, which are mainly focused on in complex networks, can be strongly
dominated by the network topology. This implies that the natures of such
heterogeneous networked systems are less likely to be lost even if the modelof network flow is simplified. The vulnerability of highly homogeneous networks like road networks has not been studied in complex networks, so it isexpected that concept application from transportation field to complex networks can contribute in this respect. Finally, we describe the universalitythat cascade size distribution of various cascading events follow power-law
with similar avalanche exponents and we mention the possibility that such
universality governs transportation systems as well.
Chapter 6 concludes this dissertation describing the achievements andrelated future tasks.