The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Research Highlights
 Hierarchical Opportunistic Routing with Moderate Clustering for Ad Hoc Networks
 Kerr-lens mode-locked Tm doped sesquioxides laser in-band pumped by an Er:Yb fiber MOPA 1.6 μm
 Geospatial information extraction from SNS: Who said what from where!
 Information science offers insights into the performance of pianist: Efficiently reading piano musical scores byanalyzing geometrical information in musical notes

Researcher Video Profiles
 Eriko Aiba, Assistant Professor, Department of Mechanical and Intelligent System Engineering Hideyuki Fujita, Assistant Professor, Graduate School Informatics and Computer Engineering Masaki Tokurakawa, Assistant Professor, Institute for Laser Science Ryo Yamamoto, Assistant Professor, School of Informatics and Engineering

News and Events
 UEC signs general agreement with VNU-UET, Vietnam
 Opening Ceremony of the UEC China Research and Education Center The Irago Conference 2017 held at UEC, Tokyo

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Hierarchical Opportunistic Routing with Moderate Clustering for Ad Hoc
Networks
The self-organizing nature of ad hoc networks generally has an advantage that the networks are free fromfixed infrastructures such as APs (Access points). However, this also has a disadvantage that the networks are
unstable and unreliable compared with wired and fixed communication.
Although there are a lot of routing protocols to overcome the drawbacks of ad hoc networks, route-based
packet forwarding of the protocols suffer from the adaptation problem due to dynamic topology changes.
Ryo Yamamoto and colleagues at The University of Electro-Communications、Tokyo, describe a novel
routing paradigm called Opportunistic Routing (OR), which is broadcast-based forwarding scheme and does
not rely on a specific route to improve route diversity and end-to-end reliability.
The main difficulty of OR adaptation in ad hoc networks is its forwarding decision done by each node since
the eligibility confirmation might be difficult in autonomous and distributed environment. Thus, we introduce
a concept of clustering and hierarchization into OR to make Cluster Heads (CHs) as a guide to forward
packets toward destination nodes.

Forwarding procedure of the proposed method (CHOR).

Computer simulations reveal that the proposed method could utilize the advantages of OR concept eliminating
its drawbacks. Namely, it could achieve higher delivery ratio with less packet forwarding compared withexisting conventional ORs.
The results also imply the proposed method could be utilized in various kinds of environment if the guide
could be found properly.
The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Reference
・Authors: Ryo Yamamoto, Satoshi Ohzahata, and Toshihiko Kato.
・Title of original paper: A Hierarchical Opportunistic Routing with Moderate
Clustering for Ad Hoc Networks.
・Journal, volume, pages and year: IEICE Transaction on Communications,
Vol.E100-B, No.1, pp.54-66, Jan. 2017.
・Digital Object Identifier (DOI): 10.1587/transcom.2016CQP0007
・Affiliations: Graduate School of Informatics and Engineering, The University ofElectro-Communications.
・Department website: http://kjk.office.uec.ac.jp/Profiles/67/0006622/prof_e.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Kerr-lens mode-locked Tm doped sesquioxides laser in-band pumped by an
Er:Yb fiber MOPA 1.6 μm
Highly efficient high power short pulse lasers at the wavelength range of 2 µm based on Tm3+ doped materials
have a variety of applications such as material processing, LiDAR, mid-infrared OPOs for wavelengths up to
12 μm, or mid-infrared supercontinuum generation. They also would enable direct coherent soft X-ray
generation by high order harmonics generation.
For these applications, a light source with much higher conversion efficiency, average power, pulse energy,
and shorter pulse duration is desirable.
Now, Masaki Tokurakawa and colleagues at Institute for Laser Science, University ofElectro-communications, Tokyo, have developed novel 2 µm high power short pulse lasers based on newtechnique of fiber laser in-band pumping and Kerr-lens mode locking with a new Tm doped gain medium
provided from University of Hamburg, Dr. Christian Kränkel.
Pulses as short as 115 fs and output power of 420 mW with conversion efficiency of ~20% were obtained.
Compared with prior SESAM mode-locked Tm doped lasers pumped by Ti:Al2O3 lasers, this new method
enabled generation of much higher output power and shorter pulse duration with higher conversion efficiency(Fig.1).

Fig.1. Output powers of Tm doped short pulse laser as a function of pulse duration.

This is the first Kerr-lens mode-locking at a wavelength of 2 μm and it opens up possibilities for new highly
efficient high power short pulse lasers at 2 μm. In the future, sub 50 fs pulse generation at this wavelength
range would be possible.

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Reference
1. M. Tokurakawa, E. Fujita, and C. Kränkel, "Kerr-lens mode-locked Tm3+:Sc2O3
single-crystal laser in-band pumped by an Er:Yb fiber MOPA at 1611 nm," Optics
Letters, 42, 3185-3188 (2017).
2. E. Fujita, Y. Mashiko, S. Asaya, M. Musha, and M. Tokurakawa, "High power
narrow-linewidth linearly-polarized 1610 nm Er:Yb all-fiber MOPA," Optics
Express 24, 26255-26260 (2016).

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Geospatial information extraction from SNS: Who said what from where!
Social media is expected to be a good source of data for analyzing human behavior and statuses of locations. It
is possible to provide location-based information simply by geospatially filtering archived data.
However, this naive approach causes problems for practical applications. For example, with Twitter, ingeneral, the location from which a tweet is posted is attached to a geotagged tweet. Specifically, the location
coordinates attached to the geotagged tweet, "Heavy rain in Miura Peninsula" by NHK (Japan's publicbroadcaster) are not those of the Miura Peninsula, but of Shibuya in Tokyo, where NHK is located. Therefore,
the tweet is be found by a spatial search around the Miura Peninsula or even Kanagawa Prefecture, where theMiura Peninsula is located.
Hideyuki Fujita at the University of Electro-Communications, Tokyo has proposed a new framework thatconsiders the relationships between data meaning and their spatial structures.

From where (orange) about what place (blue) people in Tokyo post.

In this research, Fujita particularly focused on the distinction between locations of interest (LoI) and locationsof activity (LoA). In example above, Miura Peninsula is LoI and Shibuya is LoA. Fujita proposed a method
for automatically classifying tweet locations into LoI and LoA.
The evaluation experiment that used 600,000 tweets showed good results about the precision and recall of theclassification. The method was also successfully applied to extract frequently mentioned locations whileclassifying them into those which were globally mentioned and those locally mentioned.
The results imply that this method could be applied to analyzing the relationships between location names andthe signified locations.
The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Reference
・Authors: Hideyuki Fujita.
・Title of original paper: Information extraction and visualization from Twitterconsidering spatial structure.
・Journal, volume, pages and year: Cartographica 52-2, 178 (2017).
・Digital Object Identifier (DOI): 10.3138/cart.52.2.3875
・Affiliations: Graduate School of Informatics and Engineering, The University ofElectro-Communications.
・Department website: http://www.uec.ac.jp/

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Information science offers insights into the performance of pianist: Efficiently
reading piano musical scores by analyzing geometrical information in musicalnotes
Musical scores for piano usually have a large number of notes and instructions, such as marks indicating
expression, articulation, and accidentals. When pianists sight-read sheet music, they must decode suchinformation instantly and transform it into finger actions and movement. However, it is still not clear how
pianists are able to achieve such fast decoding.
Now, Eriko Aiba and Yutaka Sakaguchi at the University of Electrocommunications, Tokyo (UEC, Tokyo)
have investigated the kinds of clues used by professional pianists for the efficient score reading that isnecessary to play complex musical arrangements eloquently and without mistakes. Aiba and colleagues
hypothesized that the common patterns of multiple notes--for example, octave, chord, scale and arpeggio--andgeometrical information--distance between two notes--are more useful compared with logical information,such as the number of ledger lines (Figure 1).

Figure 1: Example of the hypotheses.

Sixteen professional pianists participated in the experiment with the task of answering the target notes
presented on a display by striking the corresponding keys on a hybrid piano. The target notes were of three
types: a single note, an octave interval, and a seventh interval. The seventh interval played a role as aperturbation stimulus to avoid that the participants realize all target notes including two notes are the octave
interval. The target notes were presented as quarter notes on a one-bar length grand staff at the second beatposition of a four-four time measure (Figure 2).

Figure 2: Experimental procedure in one trial.

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

The experiments showed that the pianists could read octave intervals for a wider range of key positions
compared to single notes.
All the other results suggested the existence of a strong connection between the geometric information andpianists' actions, which may be presumably have been formed through long-term training.

Reference
・Authors: Eriko Aiba, and Yutaka Sakaguchi.
・Title of original paper: Visual information for efficient score reading by pianists.
・Journal, volume, pages and year: Proceedings of International Symposium on
Performance Science 2017 (ISPS2017), 46, 2017.
・Digital Object Identifier (DOI):
・Affiliations: Department of Mechanical and Intelligent Systems Engineering,
Graduate School of Informatics and Engineering, University ofElectro-Communications..
・Department website: http://www.uec.ac.jp/eng/education/ie_graduate/m/index.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Eriko Aiba, Assistant Professor, Department of Mechanical and Intelligent
System Engineering
How the brains of musicians work while playing musical instruments and multimodal information
processing.
Eriko Aiba, Assistant Professor, Department of Mechanical andIntelligent System Engineering
Assistant Professor Aiba is studying how the brains of musicians work
while playing musical instruments and their strategies for processing
huge amounts of multimodal information in parallel. In particular,
musicians who use sight reading must process enormous amounts of information. Specifically, they must readthe score, interpret the music, and search for the correct keys to play while planning the motion and control of
their fingers. So one of the important areas of research is understanding how professional musicians complete
such complicated information processing.
Furthermore, musicians have their own strategy in playing, even though it may appear that they all playing the
piano in the same way. Notably, Eriko Aiba thinks that the strategies of musicians are not completely different,
because many musicians display common traits. "In the future I would like to categorize professionalmusicians based on the type of information processing strategy used by their brains," says Aiba. "It may helpmusicians to find their own suitable ways of learning to play musical instruments."
This research is expected to contribute to many areas of research areas in exploring expertise andperformance.
Further information
Eriko Aiba, Assistant Professor, Ph. D. (Musicology)
Department of Human Media Systems, Graduate School of Information Systems
The University of Electro-Communications, Tokyo.
Website:https://sites.google.com/site/aebaeriko/
Research Highlight:
http://www.ru.uec.ac.jp/e-bulletin/research-highlights/2017/information-science-offers-insights-into-the-perfo
rmance-of-pianist.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Hideyuki Fujita, Assistant Professor, Graduate School Informatics andComputer Engineering.
Development of interactive software using geospatial information
Hideyuki Fujita, Assistant Professor, Graduate School Informatics andComputer Engineering.
Hideyuki Fujita is an expert on the development of interactive software
using geospatial information. His motivation is to analyze data fromconsumer generated media to understand locations and human behavior.
In a recent project, he has mapped geotagged photographs to arrows indicating from where to where eachphoto was taken. In this framework, he has proposed new methods for creating street view animation, spatial
search based on spatial relationships, and geospatial storytelling environment. "We will put more focus on thespatial and semantic structures of geospatial information," says Fujita.
Further information
Hideyuki Fujita
Assistant Professor, Graduate School Informatics and Computer Engineering.
The University of Electro-Communications, Tokyo.
Website:http://www.is.uec.ac.jp/staff/list/fs/fujita-hideyuki.html
Research Highlight:
http://www.ru.uec.ac.jp/e-bulletin/research-highlights/2017/geospatial-information-extraction-from-sns.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Masaki Tokurakawa, Assistant Professor, Institute for Laser Science.
Controlling light and atoms: Development of new short pulse lasers in the wavelength range of two
micrometers
Masaki Tokurakawa, Assistant Professor, Institute for Laser Science.
Masaki Tokurakawa is aiming to control 'light and atoms'. His research
is focused on laser physics, laser engineering and atomic optics, with
one specific research topic being the development of new short pulse
lasers in the wavelength range of two micrometers. This wavelength
range of short pulse lasers have potential applications including laser welding of polymer materials, three
dimensional processing of silicon materials, generation of mid-infra-red coherent pulses by nonlinear
frequency conversion, and generation of coherent soft X-rays by high order harmonics generation. For theseapplications it is necessary to improve the conversion efficiency, average power, and pulse duration of thelasers. "Recently, we have developed a new thulium (Tm) doped solid state laser with a new laser gain
medium and Kerr-lens mode-locking," says Tokurakawa. "This device has a much shorter pulse duration andhigher output power than previous reports."
Further information
Masaki Tokurakawa, Assistant Professor, Institute for Laser Science,
The University of Electro-Communications, Tokyo.
Website:http://www.ils.uec.ac.jp/~tokura/index.html
Research Highlight:
http://www.ru.uec.ac.jp/e-bulletin/research-highlights/2017/kerr-lens-mode-locked-tm-doped-sesquioxides-las
er-in-band-pumped-by-an-er.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Ryo Yamamoto, Assistant Professor, School of Informatics and Engineering
Wireless communication and wireless multi-hop networks with inter-device communication to deliver
messages to destinations
Ryo Yamamoto, Assistant Professor, School of Informatics andEngineering
Ryo Yamamoto's research is centered on wireless communication, withemphasis on so-called wireless multi-hop networks. Generally,
wireless communication is considered to be communicating byconnecting via an access point or base station like wifi, wireless LAN, or cell phone. However, in Yamamoto's
research on wireless multi-hop networks, devices relay communications with each other, and deliver them tothe destination. "I think that most people are not familiar with this form of communication. However, it isconsidered very useful for technology such as internet of things IoT," says Yamamoto. Yamamoto is mainly
studying routing technology, in particular how to make a route, who will relay it and so on.
Further information
Ryo Yamamoto, Assistant Professor, School of Informatics and Engineering,
The University of Electro-Communications, Tokyo.
Website:http://www.is.uec.ac.jp/staff/list/ns/yamamoto-ryo.html
Research Highlight:
http://www.ru.uec.ac.jp/e-bulletin/research-highlights/2017/hierarchical-opportunistic-routing-with-moderateclustering-for-ad-hoc-networks.html

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

UEC signs general agreement with VNU-UET, Vietnam
On 29 November, 2017, The University of Electro-Communications (UEC) singed general agreement withVNU University of Engineering and Technology (VNU-UET), Vietnam to promote further international
collaboration.
The signing ceremony took place at UEC and Prof. Nguyen Viet Ha, the Rector of VNU-UET, Dr. Fukuda,
the President of UEC, Dr. Nakano and Dr. Tanaka, the executive board members of UEC, Prof. Abe, the vicepresident, Prof. Ishibashi, and Prof. Pham the professors of UEC attended the ceremony. The meeting was
initiated by the welcome speech of President Fukuda. Followed by Prof. Ishibashi's research presentation, theactive discussions were made on that topic and on promoting research collaboration and student exchange
between the two universities.
VNU-UET is one the seven universities of VNU which has
affirmed its position as Vietnam's top comprehensive
multi-disciplinary academic and research center of excellence
based on international standards.
UEC believes the conclusion of the agreement is a valuable
opportunity to promote deeper and wider cooperation withexcellent researchers of VNU-UET leading UEC to further
internationalization and strengthening the quality of its
education and research.

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

Opening Ceremony of the UEC China Research and Education Center
On October 1,2017, UEC opened the UEC China Research and
Education Center in Beijing to consolidate and further strengthen
the education and research collaboration with universities,
institutions and companies in China. We held an opening ceremony
at the Beijing Friendship Hotel on October 19, and had
distinguished guests from Shanghai Jiao Tong University (SJTU),
Shenyang University of Institute (SUT), Beijing Institute ofTechnology (BIT), Nankai University (NKU), Chinese Academy

At the Academic Meetingof Sciences and the UEC Alumni Association MEGUROKAI.
The roles of this Center are as followings;
・Promote the Joint Education Projects
・Invite excellent students and researches
・Organize researcher and student exchanges
・Promote for Collaborative Project・Provide support to apply for exchange programs among China andJapan

President Fukuda at the UEC China
Research and Education Center

The meeting call of this opening ceremony was initiated by the Member of the Board of directors of UEC, Dr.
Nakano, and President of UEC, Dr. Fukuda gave a greeting address. Then, our honored guest Prof. Zhihong
YANG from BIT gave a congratulatory address and Prof. Yokoi presentedhistories and results of ourcollaboration and explained about the purpose and works of this center. Prof. Shi from BIT gave explanation
about the Beijing Advanced Innovation Center for Intelligent Robots and Sytems (BAICIRS) where this center
is located. After this, the Vice President of UEC Prof. Abe gave a closing talk.
In the Reception, President Prof. Fukuda gave opening remarks, and Deputy Director of BAICIRS Prof.
Huang gave a congratulatory speech from the guest of honor, and the Director of R&D Center for Green
Energy Automotive Electronics, Prof. Chen gave a toast. Furthermore, The Chairman of the UEC Alumni
Association MEGUROKAI Mr. Nonomura gave an introduction of Megurokai and expressed support for thiscenter. The reception was closed by a speech from Dr. Tanaka, the Member of the Board of directors and theVice President of UEC.

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

The Irago Conference 2017 held at UEC, Tokyo
The Irago Conference 2017 was held 1-2 November 2017 at the UEC,
Tokyo Auditorium. This was the 7th in this series of conferences focusedon providing a platform for networking between scientists, graduate
students, and policy makers to interact and share ideas to find solutions forsome the major issues of the 21st century.
This core theme of this year's conference was "Challenges in Materials
Science", and the proceedings included 16 invited speakers; 5 contributedGroup photograph of participants
during the morning session on 1
November 2017.

oral talks; short, 5 minute talks by the 9 participants of the Premium
Poster Session; 17 talks during the lunch time Graduate Student Session;and 77 poster presentations. A total of 150 participants attended theconference over the two days including the invited speakers from Beijing,
Germany, Italy, UK, Singapore, and Japan.
In addition to the scientists and graduate students, high students from Seiko
Gakuin High School in Kanagawa Prefecture, also participated in theconference, giving a poster presentation and actively asking questions

Students from Seiko Gakuin HighSchool describing their research during
the poster session.

during the sessions.
During the evening of the 1st November, the participants moved to the Keio
Plaza Hotel in Shinjuku, for the "AAAS Science Fall Meeting 2017／Irago
Conference 2017 Evening Session". This session included talks by guests
from MEXT, the headmaster of Seiko Gakuin High School, representatives
from Science Magazine, and the director of a sake brewer from Akita who
described the process of producing fine Japanese sake.
Irago Conference 2018 is schedule for 1-2 November 2018 at the UEC,

Takashi FUKUDA, President of UEC,
Tokyo gives a speech at the "AAAS
Science Fall Meeting 2017／The Irago
Conference 2017 Evening Session".

Tokyo Auditorium.

The University of Electro-Communications 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585© 2017 The University of Electro-Communications.

The University of Electro-Communications (UEC) in Tokyo
is a small, luminous university at the forefront of pure and applied sciences, engineering, andtechnology research. Its roots go back to the Technical Institute for Wireless Commutations,which was established in 1918 by the Wireless Association to train so-called wireless engineers
in maritime communications in response to the Titanic disaster in 1912. In 1949, the UEC wasestablished as a national university by the Japanese Ministry of Education, and moved in 1957
from Meguro to its current Chofu campus Tokyo.
With approximately 4,000 students and 350 faculty, UEC is regarded as a small university, butwith particular expertise in wireless communications, laser science, robotics, informatics, andmaterial science, to name just a few areas of research.
The UEC was selected for the Ministry of Education, Culture, Sports, Science and Technology (MEXT)
Program for Promoting the Enhancement of Research Universities as a result of its strengths inthree main areas: optics and photonics research, where we are number one for the numberof joint publications with foreign researchers; wireless communications, which reflects ourroots; and materials-based research, particularly on fuel cells.
International Public Relations
The University of Electro-Communications
1-5-1 Chofugaoka, Chofu, Tokyo 182-8585
E-mail : kokusai-k@office.uec.ac.jp
Website : http://www.uec.ac.jp/eng/

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182-8585 © 2017 The University of Electro-Communications.