List of Dissertation Abstract (Department of Information Environment)
NameSupervisor

Hasanvand

Kenta Ozeki

Morteza

Title
Coloring of planar graphs and its
relations to hypergraph coloring

MURAKAMITOMOHARU

A Study on Information Extraction

SATOSHI

NAGAO

from Manga Images and Its
Applications

Abstract
In this thesis, we investigate coloring of planar graphs andcomplete colroing of hypergraphs and use the idea of complete
facial coloring of planar graphs for the second purpose. Moreprecisely, we first show that every planar graph with maximum
degree at most Δ has the 3-distance chromatic number at most(6+o(1))Δ. In addition, we show that every subcubic planargraph has the 3-distance chromatic number at most 17 andconjecture that this number can be improved to 12. In the nextstep, we show the interpolation property of complete colroing
fails for all uniform hypergraphs; in particular, 3-uniform
hypergraphs. In our construction, planar triangulations play animportant role. As a consequence, we solve several open
problems in this concept.
This study applies CNN-based classification and detection tocomic images, which contain a complex mixture of images andtext.
First, we describe a super-resolution enlargement system usinga CNN that can enlarge all style of page images in an e-bookwhile simultaneously reducing image compression noise.
Next, a system was built to detect inappropriate objects (limitedto exposed breasts) within each frame extracted by a frameextractor, a new method capable of extracting frames within apage using CNN with accurate geometry, and the results wereshown in operation at an e-book production site.

List of Dissertation Abstract (Department of Information Environment)
NameArai Yu

Supervisor

Title

Abstract

Tsutomu

Research on the Appropriate Use ofDevelopments in machine learning have advanced everyday

Matsumoto

Machine Learning in Cyber Security

technologies such as smartphones, and their applications are

Domainwide-ranging. In cybersecurity, however, the use of thistechnology has been limited to complementing existing
methods. This study explores the potential for more active useof machine learning in cybersecurity and proposes an automatic
detection system for crime-related sites on the Dark Web. We
also identify shortcomings of machine learning in existing
antivirus products and develop workarounds. This will enablefurther appropriate use of machine learning.

Kuzuya Naoki

Tomoharu

A Study on Neural Networks for Fast

In this research, we propose a method for constructing anNagao

Inference in Embedded Systems Using

efficient neural network that replaces the conventional neuralB-spline Functions

network’s computation nodes with more efficient ones in termsof accuracy and execution time on the embedded CPUs.

List of Dissertation Abstract (Department of Information Environment)
NameSupervisor

Oyu KodaiAtsushi NomaTitle

Abstract

The maximal ideal cycles and theIn the study of normal surface singularities, the problem offundamental cycles for normal surface

comparing maximal ideal cycles with fundamental cycles is an

singularities branched over analytically important topic. This paper investigates whether the two cycles
irreducible singular plane curves

coincide on the minimal resolution of a normal surface
singularity defined by z^n=f(x, y) with irreducible f(x, y). As aresult, we proved that the two cycles coincide when n=3, and
we also calculated the fundamental genera. Furthermore, we
showed several examples where the two cycles do not coincide
when n = 4 or more.

Nakano Hiroki

Tsutomu

A Study on Impact of User-generated

The development of the Internet has led to the proliferation ofMatsumoto

Content on Cybersecurity

user-generated content (UGC) and the diversification ofinformation sharing, as well as cybersecurity issues.
This paper investigates the impact of UGC on cybersecurity
and clarifies its impact on vulnerabilities of Android
applications, the reality of attacks across multiple platforms,
and the effectiveness of shared threat information.
These results indicate that proper management of UGC byplatform operators and appropriate discarding of informationby users themselves are extremely important.

List of Dissertation Abstract (Department of Information Environment)
Name
Hamano Ryoki

Supervisor

Title

Abstract

Shinichi

A Study on Evolutionary Computation

This study targets mixed-integer black-box optimization andShirakawa

for Mixed-Integer and Mixed-Category mixed-category black-box optimization problems and develops
evolutionary computation methods for these simultaneousBlack-Box Optimization
optimization problems. The Covariance Matrix Adaptation
Evolution Strategy (CMA-ES) is one of the most promisingevolutionary computation methods, but it can only handle
continuous variables. This study establishes a simultaneous
optimization method by improving CMA-ES to a method that
can also handle discrete variables.

Gay Camille

TsutomuController Area Network Message

Automotive systems, typically consisting of a network ofMatsumotoTimestamp Analysis and its

Electronic Control Units

Applications for Automotive Security(ECUs) connected with the Controller Area Network (CAN)

Technologies

protocol, are increasingly exposed to cyber-attacks. Malware
targeting ECUs may become widespread in the future.
We identified flaws in previously proposed security
technologies and proposed various improvements andalternatives. We explored the methods that malware canemploy to detect that it is being executed in an ECU network
simulation instead of a real vehicle, and developed anenvironment that can reproduce CAN traffic with the same
properties as a real vehicle. It could be used as a malware
analysis platform or as a testbed to evaluate ECU technologies.