NTT Technical Review

August 2019 Vol. 17 No. 8
Front-line Researchers

Shingo Tsukada, NTT Fellow, NTT Basic Research Laboratories

NTT Technology Report for Smart World Technology Report for Smart World
Regular Articles
Electron Spin Resonance Spectroscopy Using a Superconducting Flux Qubit

Global Standardization Activities


Activities of ITU-T Study Group 5 (Environment, Climate Change and Circular Economy) andDiscussion Results

Practical Field Information about Telecommunication Technologies
Countermeasures against Insect Damage to User Equipment—Repellent Sheet and Repellent
SpiralExternal Awards/Papers Published in Technical Journals and Conference Proceedings

Front-line Researchers

By Utilizing the “Swing-by Model,”We Can Convert the Environment
around Us to a Source of Power
Shingo Tsukada
NTT Fellow, NTT Basic ResearchLaboratories
Overview
Japan is a so-called super-aging society, with people aged 65
and older accounting for over 25% of its population. The needs forearly detection of diseases and care for elderly people living alone
at home are increasing, and it is urgently needed to establish highprecision measurement of biological signals and a platform forprocessing biological information. In the meantime, society is
rapidly globalizing. We asked NTT Fellow Shingo Tsukada of
NTT Basic Research Laboratories what kind of stance researchers
should take as they tackle research in such an era.
Keywords: hitoe, bioelectrode, interdisciplinary research

Taking up the challenges of medical diagnosis,
health promotion, and the sports field from theviewpoint and insight of a former clinician—Tell us about your current research.
My current research involves the application of asensing fabric called hitoeTM in three areas: medical
diagnosis and treatment, sports and health promotion,and safety management and monitoring. On the basisof my experience as a clinician, I have been keenly
aware of the need for technologies that help treat diseases that are difficult to cure and technologies forfinding diseases faster, so I have been involved inbasic research on those themes. As my research progressed, I focused on the bioelectrodes used to connect weak signals in the body to an electronic circuit,and I thought that PEDOT-PSS,* a conductive polyNTT Technical Review

Vol. 17 No. 8 Aug. 2019mer being studied at NTT Basic Research Laboratories at that time, would be suitable for bioelectrodes.
PEDOT-PSS is very fragile when it gets wet on contact with water, and that fragility is a major barrier
regarding bioelectrodes used in wet environments.
However, we overcame this problem by coating
PEDOT-PSS onto surgical silk sutures, so it can now
be used for bioelectrodes. After that, in collaboration
with Toray Industries, Inc., we replaced the silk fibers
with polyester nanofibers (700 nm in diameter),which we developed and commercialized as the sensing fabric hitoe.
Although hitoe has been practically applied, it continues to be researched. Its usefulness will only berealized when it becomes popular. To ensure that*

PEDOT-PSS: poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate)1Front-line Researchers

happens, it is also necessary to deal with it as a business. Since hitoe was developed, wearable productswith similar functions—such as smart watches thatcan measure heart rate—have hit the market one after
another, and they have rapidly gained popularity as
simple heart-rate measurement devices. However,measurements taken in a person’s daily life or when aperson is exercising tend to increase distortion, loss,
and noise in the measurement data, but using suchmeasurements in medical examinations such as electrocardiograms requires very high precision. Fields
that require high-precision measurements that are difficult to handle with such common wearable products
are areas in which hitoe is being actively applied.
In collaboration with medical institutions and otherpartners, we are currently focusing on promoting the
spread of hitoe in the medical, sports, health-promotion, safety-management, and elderly-care fields. In
the sports field in particular, with an eye on the major
event to be held in Tokyo in 2020, efforts to strengthen athletes are underway, and we expect hitoe to be
utilized in such programs.
—I heard that you took up the challenge of measuring
a race car driver’s vital signs during an IndyCar
Series race, the highest peak of formula racing inNorth America.
When it first came out that we wanted to measurevital data of racing drivers, it was half a year before
the IndyCar Series racing season started. We had no
idea that an IndyCar race takes place in such a harshenvironment, and we did not have the necessary
information concerning the car, so we were gropingin the dark. I made some time between my other tasks
and handcrafted a wearable sensor based on a
research prototype. However, it looked as if I
wouldn’t make it in time. I did everything I could bymyself from processing the surface of a fireproofing
garment to wiring and attaching transmitters. Eventually, I had to go to the site and check it, so I went to
Indianapolis. On the international flight there, I
sewed the wearable sensor into the garment to beworn by the driver.
We were able to get the cooperation of the famous
IndyCar driver Tony Kanaan and some excellent
engineers. In addition, we obtained valuable information that could not be understood unless on site. We
then went through a series of trial and error experiments, at the end of which, we managed to make it intime for the actual IndyCar race.
A major factor in our success was that the special
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Vol. 17 No. 8 Aug. 2019

areas of responsibility of each party were combined
skillfully—like the pieces of a jigsaw puzzle—tomake the project a success. To be honest, the project
would not have been a success if those members were
not involved (Fig. 1). Although both the level of skills
required and the schedule were tough, it was a greatcollaborative effort. We leveraged this experience tocarry out measurements at other motor races, and it
seemed that everyone was surprised at the quality ofour technology.
What I have reaffirmed through such experiences is
the importance of going to the site and working
directly on manufacturing. If the manufacturing work
is left entirely to others, it will soon become a virtualworld with a poor sense of reality. Some people at thefactory, including people at our partner companies,
are doing hard physical work, while others are coding
and solving bugs in programs. If you get involved in
the actual work as much as possible, you will understand their hard work, and you will feel the sense ofreality of the research itself. Probably because I’mclumsy, I tend to make a lot of mistakes when I try to
do things in an easier way, so I inevitably go by trial
and error. By going through trial and error, you get toknow what processes are time-consuming, and if you
fail you can see why.
Interdisciplinary research has become common.
Constantly check your competence in a
global society.
—You recognize that the world has largely shiftedfrom the conventional style of research.
As for the environment surrounding research, theframework of research has changed dramaticallybetween the 20th and the 21st centuries. Those who
can respond to this change are likely to increase theirchances of success in the future. If we look back at
the state of scientific research from the early 20th
century to the middle of the 20th century, it seems
that many of the initial important tasks in each field
were tackled by a handful of experts. Then, in thesecond half of the 20th century, applied research anddevelopment (R&D) became the main force, and thenumber of people involved in it increased as theamount of information grew exponentially. Since thetime when there were only a few specialists in a particular area who led in that field of specialization, we
have entered an era in which the overwhelming
amount of information obtained through the collaboration of many researchers does the leading; in other2

Front-line Researchers

ECG from hitoeTM

noise

noise

HR 181 BPM
Breaking (341 km – 137 km/h)

ECG: electrocardiogram
HR: heart rate

Fig. 1. Initial members and a driver of the IndyCar Series race project with hitoeTM and the results of biosignal measurement.

words, the information itself has power.
In response to this explosion in the amount of information, signal processing that handles a large amountof data—as represented by machine learning—has
made remarkable progress, and various fields are facing upheavals. At the same time, interdisciplinary
research is advancing internationally at a speed
beyond imagination. It is fine for researchers to focus
on a single area of expertise in the conventional manner. However, the environment surrounding research
has also changed with the times, and it may seem as
if it has become difficult to continue research in one
area or specific subject for a long period of time.
Since we have entered such an era, I think it is important to study themes beyond one’s specialized fieldfrom time to time and to learn the external situation
through cross-disciplinary exchanges. It may become
more common to expand one’s research area andwork across multiple areas.
—It seems that researchers must change their own
way of thinking.
I feel that creating something original in today’s
highly globalized environment is tough for researchers. Immediately after the introduction of hitoe, wearable sensors appeared one after another around the
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Vol. 17 No. 8 Aug. 2019

world, and many products similar to hitoe were marketed. However, the boom in wearable sensors has
ended, and we have now entered the age of culling ofsome of them. In this globalized world, as soon as abreakthrough or research result is noticed, rivals—
sometimes even challengers from all over theworld—emerge.
Future innovations may need to have the impact ofchanging existing values. Society does not notice theimprovement level in which something a little moreconvenient is made. And even if we struggle to bringa new technology to the world, we don’t always taste
success. Multiple hurdles must be overcome before
we can spread it in society and earn a stable income.
With the emergence of rivals and rapid commoditization of technology, we are conducting R&D that
focuses on what can only be done with hitoe.
For example, we are promoting a project to apply
hitoe in the area of rehabilitation at Fujita Health
University Hospital (Fig. 2). In this case, hitoe isbeing used to monitor the status of exercise andrecovery from the amount of activity and the heart
rate of patients in the hospital. Compared with themonitoring of healthy young people, monitoring ofelderly hospitalized patients—who have small pulse
signals—is problematic because those signals are difficult to measure with a normal optical-pulse-wave
3

Front-line Researchers

Data management
and notification

ViewerIn-hospital network
ReportSmartphone

Relay device

Gateway(smartphoneless)Feedback to patient

DoctorUse data for high-quality research and instructions.

hitoe
transmitter

hitoe wear
for rehabilitation

hitoe
transmitter

Therapist
Design an activity schedule with a deep understandingof the rehabilitation efforts of patients.
Nurse
Correctly understand the actual conditions of patientssuch as sleep status (waking up at night).

Rehabilitation ECG and acceleration data
room etc.

Hospitalroom etc.

Benefits for healthcare workers

Fig. 2. Activity estimation and data-relay technology for rehabilitation support.

meter. That being said, accurate values must be used
as an evaluation index for rehabilitation. Under thatsevere condition, the strength of hitoe, which measures heart rate from cardiac potential, is utilized. It
can meet the expectations of experts, and it is configured so that people who wear it will not feel inconvenienced. For that reason, hitoe is currently in thephase of being optimized for specialized areas thatcan make use of its features.
The speed and fierceness of competition due toglobalization is enough to make researchers cry.
When I studied abroad, I felt that research was truly a“global professional society” in a world where
research professionals were competing on the worldstage just as the world’s athletes will compete inTokyo in 2020. It is thus necessary to train oneself,
create an environment, and prepare the necessary
conditions to win. However, the style of Japanese
researchers sometimes seems to be far from the
speedy research style of their Western counterparts. It
is likely that some researchers only focus on the topics of the research areas to which they are related anddo not pay attention to changes in the environmentand society surrounding their research. It is better toevaluate where you are in relation to the global environment by applying objective measures from time totime.
I am trying to recognize the need for that evaluationand to do it myself. That evaluation involves not only
NTT Technical Review

Vol. 17 No. 8 Aug. 2019evaluating one’s output of published papers andamount of knowledge but also focusing on a comprehensive evaluation that includes skills, researchstyles, and one’s philosophy of research. In particular,
Japanese workers should maintain an awareness oftime and deadlines and also pay attention to work
efficiency. Compared with other nationalities, Japanese people, including those involved in research
activities, tend to set vague deadlines, so it may beunsurprising that they often work endlessly without
setting time limits. Since we lack a sense of completing tasks before key deadlines, we may feel like weare passing time vaguely and will somehow manage
because we still have tomorrow.
Only a “handyman” has the chance to grasp real
intentions, so go out and meet people!
—What kind of consciousness do you have when confronting such a great change?
I’m aware of my own sense of time, so I try to be as
quick as possible. Even if one has such awareness,others do not necessarily have the same awareness.
As with athletes at sporting events, it is important for
researchers to set a time goal when achieving results,
because no matter how good the results are before orafter the tournament, they won’t be evaluated positively. This is because people (the evaluators) tend to4

Front-line Researchers

focus on the main event such as a race, rather than allof the practice sessions before and after it. I am
always trying to be aware of issues related to time andto finish tasks as quickly as possible.
Because I’m clumsy, I’m often taking detours.
Although I sometimes waste time, I try to be aware of
how I can work efficiently in a focused manner. And
I think above all else, the most important thing is totake action. Whether it is called agile development or
not, we do not completely set specifications from the
beginning; instead, we plan our R&D activities tobetter meet the needs of our customers, including
those needs concerning technologies and specifications.
In the area of medical care, that situation might beclose to the treatment given to an emergency patienton their initial medical examination. In the case ofnon-emergency medical care, treatment progresses as
test results are reviewed, so diagnostic treatment canbe performed systematically. In contrast, in emergency care with a patient transported by ambulance,
it is necessary to judge the patient’s condition immediately from a limited amount of information and test
values. Sometimes emergency surgery is required, so
it is necessary to be responsive. In regard to R&D as
well, I think we should get out into the field as muchas possible, meet face-to-face with customers andpeople in charge, find out their true needs, gather
necessary technologies, and start R&D promptly.
Moreover, instead of just listening to requests in thefield, we are constantly striving to increase theamount of technology, knowledge, and tools that we
can apply so that we can respond promptly to various
requests. I must admit though, if I do too much, things
get out of hand, and I forget what my specialty is.
Customers may think of me as a “handyman.” I
think that people feel free to talk to such a “jack of all
trades” so they speak their mind. As a result, we cangather more down-to-earth information and get newideas from the motivation obtained on the spot. Andin parallel with the work of gathering the needs of themarket, we will work on development while sharing
efforts in collaboration with experts knowledgeable
in matching seeds. If you work in collaboration withexperts in each area, you will be involved with people
in more fields, and that involvement will make thatwork more significant. I always try to put all myeffort into solving problems that our customers talked
to us about. Sometimes I do too much as a handyman
and exceed my workload limit. As a researcher, I try
to ensure that I take rests and spare as much time as
possible to scientifically explore the subject.
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Vol. 17 No. 8 Aug. 2019

The swing-by model can correct the trajectory of
R&D and accelerate it in the direction in which it
can proceed.
—How will you conduct research activities going
forward?
I have two dreams. One is the development ofadvanced medical devices. I have a desire to create
products that are evaluated positively by experts. For
example, I’d like to make a new electrode for cardiac
pacemakers with Japanese technology. It is one of themost difficult medical devices to fabricate, and presently it is mostly made outside Japan. The other is totry to detect signs of the onset of sickness and serious
symptoms. The first stage of sensing technology has
almost reached its goal; however, the second stage,
which is signal processing, is very difficult. Although
we are struggling at this stage, we are resolutely
developing new methods while enjoying the challenge.
—What would you like to say to young researchers?
First, you should build up your basic strength. I
think it is important to steadily build up your own
specialized area from the basics. For example, in thecase of informatics, I think that it is possible to properly evaluate the validity of the currently popularmachine learning only by learning the basics of mathematics, statistics, and neuroscience behind the technology and by utilizing that knowledge in practice. I
hope that you gain a solid foundational strength thatenables you to grasp, analyze, apply, and build things
correctly, and gain on-site experience. Second, youmust grasp your position on a global scale. Although
it is also my personal commandment, receiving
objective and international assessments on a regularbasis is a very tough but necessary one. To that end,
I’d like you to write a research paper, make a presentation at a conference, and interact with researchers.
This is an age when it is easy to develop such activities across borders, so I hope that you can go out fromNTT and deepen exchanges with other researchers,
regardless of your skill in English.
If I may digress, I’m interested in the asteroid
explorer Hayabusa. Many planet probes such as
Japan’s Hayabusa and those of NASA use the “swingby” principle to reach target planets. Swing-by is ameans of navigation to reach a planet; that is, as aspacecraft traverses the solar system and approaches
a certain planet, it is accelerated by the gravity and5Front-line Researchers

motion of the planet, so its trajectory is altered. Then,by repeating the fly-by with other planets, the spacecraft can travel to its destination planet by expending
less energy.
Actually, I thought that our R&D was progressingin the same swing-by manner, so I named it the“swing-by model.” When the seed (i.e., a research
theme = a small satellite) approaches the area of
attraction (i.e., the need = a planet), its trajectory is
directed toward the planet (the need), the development is then accelerated by the attraction of theplanet, and its trajectory can be corrected (i.e., thedirectionality of the development is determined). By
repeating the swing-by, you can further increase yourspeed and boost your amount of experience. If you
have a distant destination that is slow to reach at firstand you cannot reach it by yourself, take advantage ofthe chance to approach nearby planets, and if you
courageously take one step toward your needs (planets), you will be able to accelerate, gain valuable
experience (kinetic energy), and get a chance to fly
far.
If you are worried that you are not the type of person who’d make the first move, the first step is to try
it and start small by yourself. Or if you don’t have thecourage, you can do it as a hobby. Try your favorite
things in your own time. I’m presently searching fora method of biosignal processing. Although I think
my pace is rather slow from the viewpoint of a specialized teacher, I’m enjoying increasing my knowl-

NTT Technical Review

Vol. 17 No. 8 Aug. 2019edge outside my field as I read textbooks for highschool and university students. It’s also fun to buy
electronic parts and handicraft materials and makethings on your own. Being a little adventurous willlead to the first step.

Interviewee profile
Shingo Tsukada
NTT Fellow, NTT Basic Research Laboratories.
He received an M.D. from Toyama Medical andPharmaceutical University and a medical license
in 1990. He received a Ph.D. in medicine from the
University of Tsukuba, Ibaraki, in 2003. He wasa visiting researcher at the University of California
at San Diego from 2003 to 2005. He joined NTT
Basic Research Laboratories in 2010 as a
Research Specialist. He has been studying themechanism and activity control of signal transduction of brain cells. His current interests
include the detection of biomedical signals usingnovel wearable-type and implant-type bioelectrodes based on the composites of conductive
polymers with various fibers and textiles. He is amember of the Physiological Society of Japan,
the Japan Society of Applied Physics, theJapanese Circulation Society, and the Japanese
Orthopaedic Association.

6

NTT Technology Report for Smart World

Technology Report for Smart World
Yasushi Matsuno
Abstract

NTT Research and Development Planning Department has selected 11 key technologies for realizing
a smart world based on social trends for the next 7 to 10 years and published “NTT Technology Reportfor Smart World.” This article introduces a summary of these 11 technologies and the social changes thatwill be brought about by such technologies.
Keywords: smart world, technology trend, social trend

The Smart World is Inevitable
The Smart World is not just some imaginary ideal.
It is a future that will inevitably arrive. The more thattechnology advances, the more data, work, people,
and industries that were once separate will become
intertwined and “smart.” Collaborative connections
will enable new co-creation that could not haveoccurred before, accelerating the Smart World evenmore.
The term Smart World refers to many different
things, as smart technology is introduced in fields
including smart cities, smart mobility, smart manufacturing, smart entertainment and smart healthcare.
For example in the manufacturing sector, work isunderway on an industry-wide platform to tap into
the knowledge of skilled workers and construct a connected value chain, and investments are being madein a variety of AI and speech recognition, sensing,and networking technologies.
Building the Smart World is a vital step for solving
many of the social challenges confronting society
today. Contemporary social issues such as food waste
and environmental destruction span a wide range offields, and cannot be solved simply by reforming one
company. In order to solve social issues and create aricher society, we should strive for a smart world thatenables co-creation across corporate and industry
boundaries.
We have been working for some time on a “B2B2X”
business model that will accelerate the creation of theSmart World. This model aims to create new value by
having major industry players take advantage of new
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Vol. 17 No. 8 Aug. 2019

technologies that we have developed together with
our partner companies. We want to accelerate thenecessary transition to the Smart World in order toachieve a more sustainable world and richer lives.
Technology Must Be Natural
In the Smart World, it is essential that people of allages, genders, occupations and ethnicities benefit
from technology. This is why technology must be
natural. Using current cutting-edge technologies suchas virtual reality (VR) requires clear awareness, andsometimes specialized knowledge. This leads to disparities between those who can benefit from technology and those who cannot. Accordingly, technology
must become so natural that people are unaware of its
presence.
The advent of natural technology also promises lessstressful lives. AI that can converse naturally likehuman beings would make it possible to communicate beyond simple questions and answers, whilemore natural everyday devices could eliminate theneed to worry about various settings and operations.
Natural technology is a crucial concept for eliminating stress in all fields and for people to live comfortably.
In the past, we have understood technology as
something in conflict with humanistic things andnature. Accordingly it has sometimes been seen as
lacking humanity or warmth. However, as technology
grows more natural in the future, it will overcome this
opposition and become integrated into what we havethought of as human values and emotions, contributing
7

NTT Technology Report for Smart World

to a good environment for both the Earth and humanbeings.
As technology becomes more natural, it shouldgrow better at supporting human activities on a
deeper level. Technology must be natural in order forhuman beings to display their creativity and increase
their own value—to truly expand human potential
and unleash groundbreaking innovation.
11 Technologies for the Smart WorldWe are focusing our energy on 11 technologies thatwill contribute to natural technology and the SmartWorld—from maturing technologies beginning to be
being implemented in a wide range of fields toemerging technologies that should flourish in the
future.
Learn how these 11 technologies will bring about
the Smart World.
1. Artificial Intelligence
Technology that is tolerant and sincere
The basic abilities of artificial intelligence (AI) tosee, listen, and speak are reaching practical levels.
However, this only means that separate functions canderive standardized outputs, and are still unsuited todealing with complex problems. AI is being developed that can handle more complex problems bystreamlining learning and creating “white box” algorithms. In addition, we believe that AI needs to beable to process human values. AI that can present a
number of options tailored to diverse values will
deepen human thought by offering multiple solutions,even for more complex problems. AI that can “think”
in accordance with people’s values is technology withthe tolerance to accept diversity, and the sincerity torespond to different ways of thinking.
2. Virtual Reality / Augmented Reality
Creating moving experiences across time andspace
Virtual reality and augmented reality (VR/AR)
have already been released as part of various services,
products, and content, but we want to naturally introduce this technology into an even wider range offields in the future. For that purpose, we are focusing
our VR/AR research not only on enriching qualitative
expression but also speeding up processing. Our
research includes technology that stimulates senses
beyond vision such as hearing, touch, force, and temperature, in addition to technologies such as “Kirari!”that can transmit entire spaces over distance via realNTT Technical Review

Vol. 17 No. 8 Aug. 2019

time high-speed data processing. By reducing latency, Kirari! 2.0 will even overcome time. People’s
experiences in the Smart World may evolve into
something completely different from today.
3. Human-Machine Interface
Deeply understanding humans to naturally integrate with robotics
The Smart World will not only bring updates to
products, systems and services. In the future, humanmachine interfaces (HMI) will also extend the humanbody. Brain wave analysis and other methods haveunraveled mysteries of brain function, which coupledwith much-improved understanding of the mechanisms of the human body, should lead to the creationof more sophisticated and complex interfaces.
Through our HMI research such as Point of Atmosphere (PoA), we aim to naturally integrate humans
with their environment and robotic devices. With the
new technology we envision, people will be able tosubstitute lost bodily functions and make use of information that natural senses cannot detect. Just as virtual and augmented reality expand the human senses,
human-machine interface (HMI) expands the body’s
potential—indeed, the very body itself.
4. Cyber Security
Shifting to active defense
As the spread of networks and IoT increases therisk of cyber terrorism, existing passive cyber security technology tends to result in a back-and-forthbattle against constantly evolving attackers. In order
overcome this situation, a shift towards active security centered on the use of AI is underway around theworld. Stronger security is essential to our vision of
the Smart World where everything is networked. In
addition to developing security technologies adapted
to a wide range of applications including mobility,
plant systems, and healthcare, we are focusing on
active defense that actively deals with cyber attacks.
The Smart World will show its true value only withthe establishment of new security technologies that
can head off cyber attacks.
5. Information Processing Infrastructure
Making strides in real-time, scalable processing
infrastructure
Next-generation information processing technology could be called the infrastructure of the SmartWorld. Thus, effective utilization of rapidly evolving
technology requires building out information processing infrastructure. Attention in this field is
8

NTT Technology Report for Smart Worldfocused on technology that can overcome the tradeoffs between performance and flexibility or power
consumption. We are also hard at work developing
new information processing platforms that surpass
conventional limitations. Projects currently underway include scalable data processing technology toprocess large amounts of information in real time,and highly efficient data management technology topromote use of data across industries. Of course, we
are also making efforts to improve hardware itself
and develop new technology that can overcome
Moore’s Law. The fruits of this research are leading
to the emergence of new infrastructure.
6. Networks
Creating a breakthrough all-photonic network
New networks are key to realizing the Smart World,
where rich flows of data will connect numerous
actors and products across industries. We are embarking on the creation of new networks that surpass the
5G technology entering use in the near future. These
networks must be higher capacity, lower latency,
stronger and more flexible, as well as energy efficientin order to address the explosive increase in energy
consumption. That is why we are working hard toconvert to an all-optical network and pursuing creation of new networks. We will lead the way to a newworld as these new networks spur innovative collaboration.
7. Energy
Realizing an intelligent energy network
As various advanced technologies enter practicaluse and the world’s population increases in the future,
the energy needed to power systems in every industry
is a key part of the social infrastructure of the SmartWorld. In order to meet growing energy demand
while also managing environmental issues, research
institutions around the world are trying to improvehigh-capacity storage batteries. To create this newsocial infrastructure, we are also hard at work developing energy that is not only environmentally friendly and high capacity, but able to be freely distributed
as if it has intelligence. Accordingly, we are conducting efficient energy distribution through virtual
power plants that virtually manage dispersed energy,
while also embarking on research into new hybrid
energy networks. In the Smart World that we arebuilding, energy will evolve into something smartthat can circulate almost as if intelligent.

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8. Quantum Computing
Innovation with post-Moore’s Law technology
Quantum computing technology, which is expected
to vastly outperform conventional computers, islikely to be used in nearly every industry. Quantum
computing is often discussed in relation to solving
optimization problems that require the testing of endless numbers of choices, but in the future it may also
result in breakthroughs in the energy and drug discovery fields. Our quantum computing research has
made remarkable progress in recent years, with technologies such as LASOLV introducing new concepts
distinct from conventional quantum computing
including gate type and annealing type. At the sametime, we are also pursuing research on quantum computer hardware utilizing quantum gates, and significant advances in both software and hardware are
expected in the future. Quantum computing does not
merely provide extremely fast computing technology,
but has the potential to transform information processing itself. In the Smart World, quantum technology will change the way information is handled.
9. Biotechnology / Medical Care
Evolution of biosensing leads to precision medicine
Hand-in-hand with advances in biology and chemistry, biotechnology is also steadily evolving. Biotechnology is mainly being introduced in medicine,
as well as agriculture, forestry and fisheries, but amid
the changing nature of information today, biotechnology actually reveals new possibilities for communication. We are also approaching biotechnology froma number of directions spanning the fields of chemistry, biology and physics. In particular, research is
ramping up in recent years in the field of biomedicalcare. In addition to our development of functional
materials such as “hitoe,” in 2019 we entered into
research partnerships with Australian institutions
including Deakin University and Western Sydney
University. We will accelerate our activities going
forward as part of our vision of “a society where
elderly people can live independently and safely.”
10. Advanced Materials
Innovative production expands the concept ofmaterials
In the future, instead of conventional fixed materials, multifunctional materials that change flexibly inresponse to the environment will become commonplace. In fact, research into new materials such as
nanomaterials is making steady progress, and numerous
9NTT Technology Report for Smart World

materials are beginning to enter practical use. In orderto further advance research and development of newmaterials, we are using AI and other methods to speed
up the development process. In order to build the
Smart World, rapid development of materials isessential to meet demand for development of personal functions tailored to people’s diverse needs. We
plan to pursue development of these new materials,
and are already making progress with some technologies such as advanced thin films that will be used tocreate more flexible and functional materials.
11. Additive Manufacturing
Personalized production in every field
Additive manufacturing, frequently symbolized by
3D printing, will become an indispensable technology in the Smart World by enabling greater personalization. Additive manufacturing makes possible morethan just items such as industrial products and building materials. In the future, even parts of the humanbody including bones and organs are expected to be
manufactured at will. Currently, interest is growing in
the field of bioprinting. We are also working on
research and development of artificial cells in a layered structure. Another technology to watch is 4D
printing, which could incorporate information onchanges in time and condition to enable self-healing.
As this technology evolves, it will be possible tomanufacture more personal products.
A booklet entitled “NTT Technology Report for
Smart World” that describes these 11 technology
trends and NTT R&D initiatives was published [1].
We hope that this report will be useful in communicating with customers.
Reference[1]

NTT Technology Report for Smart World, http://www.ntt.co.jp/RD/e/techtrend/index.html

Yasushi Matsuno

Manager, R&D Planning, NTT Research andDevelopment Planning Department.

NTT Technical Review

Vol. 17 No. 8 Aug. 201910

Regular Articles

Electron Spin Resonance
Spectroscopy Using a
Superconducting Flux Qubit
Hiraku Toida, Kosuke Kakuyanagi, William J. Munro,
Hiroshi Yamaguchi, and Shiro Saito
Abstract

We use a superconducting flux qubit for the sensing application of electron spin resonance (ESR)
spectroscopy. The superconducting flux qubit is a highly sensitive magnetometer with micrometer-scalespatial resolution. The sensitivity of our spectrometer is 400 spins/√Hz, and the sensing volume is 0.05
pL. This high sensitivity and high spatial resolution enable us to investigate a small number of electron
spins in a microscale area. The spectrometer also obtains a wider ESR spectrum range with twoparameter (frequency and magnetic field) scanning. This enables us to refine the material parameters.
Keywords: superconducting flux qubit, electron spin resonance, sensing

1. Electron spin resonance
The spin resonance phenomenon occurs in various
actions undertaken in ordinary life, for example,
when visualizing the properties of a human bodyusing magnetic resonance imaging (MRI). The targetof MRI is nuclear spins in atoms (nuclear magnetic
resonance: NMR), but electron spins are also goodtargets for the spin resonance technique. Historically,
the proof-of-principle experiment of electron spinresonance (ESR) occurred earlier than NMR.
ESR is a commonly used tool to investigate theelectron properties in materials. An electron spin canbe considered as a small magnet. When an external
magnetic field is applied, the electron spin has different energy depending on its orientation to the external
magnetic field. The parallel spin is more stable (lower
energy) than the antiparallel one (Fig. 1). To detect
this energy splitting as an X-band microwave
response, a magnetic field of around 300 mT is usually applied to the spin. The energy splitting can thenbe investigated by measuring the microwave transmittance because if the spins resonate with the microwave, the spin resonance will appear as microwave
NTT Technical Review

Vol. 17 No. 8 Aug. 2019absorption. This microwave response of the spin contains information on the target material, and the spectrum is considered to be a fingerprint of the material,
which can be used to identify the material.
In standard ESR spectrometers, microwave cavities(metal boxes) are utilized as a sensor to detect theelectron spins. The target sample is enclosed in thecavity, and the microwave transmittance of the cavity
is measured as a function of an external magnetic
field. However, we use a magnetometer to sense thestate of the spins because if the spins resonate withthe microwave, the spin resonance can also be detected as a change in the magnetic field generated by thespins. In this work, we have developed an ESR spectrometer with a superconducting flux qubit thatworks as a magnetometer with a micrometer-scalespatial resolution.
2. ESR spectrometer with a superconducting
flux qubit
We investigated a magnetometer based ESR spectrometer using a superconducting quantum interference device (SQUID) [1, 2]. The sensitivity was
11Regular Articles

Antiparallel(Higher energy)

B=0

Ma
gn
eti

cf

iel

Energyd,
B

Microwave

B>0

Parallel(Lower energy)

Superconducting flux qubit

Microwave line

Microwave line

Fig. 1. Energy diagram of an electron spin under a magnetic field B. Energy degeneracy is lifted by applying an external
magnetic field to the spin. This energy splitting can be investigated by applying a resonant microwave signal.

10 µm
Readout circuit for a superconducting flux qubit(Connected to room temperature electronics)

Fig. 2. Scanning microscope image of the superconducting flux qubit. The blue loop is the superconducting flux qubit. Purple
patterns are microwave lines to excite the superconducting flux qubit and spins. Green patterns are an on-chip
readout circuit for the flux qubit connected to room temperature electronics.

improved from 106 spins/√Hz to 15,000 spins/√Hz by
improving the magnetic sensitivity of the SQUID
magnetometers using a faster readout method of the
SQUID.
Here, we use a superconducting flux qubit as a sensitive magnetometer to sense the magnetic field generated by electron spins to further improve the sensitivity [3]. A scanning electron microscope image ofthe device is shown in Fig. 2. The superconducting
flux qubit (blue false-colored area) senses a magnetic
field through the loop structure.
The experimental setup of our ESR spectrometer isshown in Fig. 3. We prepare the superconducting flux
qubit on a silicon substrate. The target sample isdirectly attached on top of the substrate. Magnetic
fields are applied in two directions. An out-of-planemagnetic field is applied to control the flux qubit,
NTT Technical Review

Vol. 17 No. 8 Aug. 2019

while an in-plane magnetic field is applied to polarize
the spins in the target sample. A microwave line near
the flux qubit is used for two purposes: for the spectroscopy of the flux qubit and for exciting the spins inthe sample. In the experiment, only one line of the
purple false-colored area in Fig. 2 is used. The stateof the flux qubit is read by the readout circuit fabricated on the same chip (green false-colored area in
Fig. 2) which is connected to room temperature electronics. The experiment is performed below 20 mK
using a dry dilution refrigerator.
The principle to detect a magnetic field using a
superconducting flux qubit is depicted in Fig. 4. The
flux qubit is the artificial atom whose energy structure (Fig. 4) is controllable by an external magnetic
field. If an external magnetic field is applied to theflux qubit, the energy level curve shifts from the blue
12

Regular Articles

SampleQubit readout circuit(Room temperature)

Qubit
controlB

Qubit excitation
it

b
Qu

B||
Spin polarization

ine

el

av

ow

cr
Mi

S

ate

str

ub

ns

o
ilic

Spin excitaion

Resonance frequency of a qubit

Fig. 3. Experimental setup. A target spin ensemble (yellow) is directly attached to the flux qubit substrate. Two magnetic
fields—in-plane (red) and out-of-plane (blue)—are applied to the sample to control the spins and the flux qubit,
respectively. Microwave tones to excite the flux qubit and the spins are mixed in the room temperature electronics
and sent to the same on-chip microwave line.

Depolarized(No magnetic field)
ƒq

Response of a qubitMagnetic field from spins

Polarized(Finite magnetic field)

Operation point
Magnetic field applied to a qubit

Fig. 4. T he principle to detect a magnetic field using a superconducting flux qubit. The blue (red) curve corresponds to thespectrum of the superconducting flux qubit with (without) a magnetic field from the spins. When the operation pointof the flux qubit is fixed at a specific point (green), the magnetic field signal is converted to the change in theresonance frequency of the flux qubit.

one to the red one. This change in the magnetic field
can be converted to the change in the qubit resonancefrequency by fixing the operation point of the qubit ata specific point (green dashed line). Thus, we canmeasure the magnetic field shift by monitoring thequbit resonance frequency. In our experiment, thedetected magnetic field shift is caused by the change
in the electron spin alignment, namely, the polarization ratio (Fig. 4).
To excite the spin ensemble, we use a microwave
line near the flux qubit. When a microwave signal isapplied to the line, electron spin near the line isexcited, and this changes the magnetic field when theenergy splitting of the spin resonates with the microwave energy. We detect this change in the magnetic
NTT Technical Review

Vol. 17 No. 8 Aug. 2019

field generated by the spin system using the flux
qubit. In the experiment, we sweep the microwave
frequency of the spin excitation to obtain the ESR
spectrum of the target material.
3. ESR spectroscopy ofnitrogen-vacancy centers
We use nitrogen-vacancy (NV) centers in diamond[4] as a target sample of ESR spectroscopy. A measured ESR spectrum under the fixed in-plane magnetic field of 5.8 mT is shown in Fig. 5(a). The two
sharp dips at around 2.8 GHz and 3.0 GHz appear toreflect the electron spin properties of the NV centersbecause NV centers have a three-level structure
13

Regular Articles

(b)

(a)
50

−1.5

45

−2.0
−2.5

Switching probability (%)−1.0|0| + 1

−0.5

40

−3.0
2.7

2.8
2.9
3.0
Spin excitation frequency (GHz)Spin resonance frequency (GHz)

3.05

0.0
|0| − 1Magnetic flux shift (m0)

0.5

3.00
2.95

2.85

|0

2.80
2.75

3.1

| ± 1

2.90

0

2

4

6

In-plane magnetic field (mT)Fig. 5. ESR spectrum of NV centers in diamond. (a) ESR spectrum measured under a fixed magnetic field of 5.8 mT. The
magnetic field is applied along the [100] direction of the diamond crystal. The arrows indicate the position of theresonances. A measured magnetic field shift is converted to a magnetic flux shift through the qubit loop. (b) ESR
spectrum as a function of an in-plane magnetic field. The symbols are experimental data, and the lines are fitted
curve. ((b) inset) Energy level structure of NV centers in diamond.

(Fig. 5(b) inset). After repeating this measurement
for various magnetic fields, we plot the peak positionof the spectrum as a function of the in-plane magnetic field (Fig. 5(b)). The positions of the peaks split
into two branches starting from the position of thezero field splitting of 2.88 GHz. The material parameters of the NV center can be extracted by fitting theexperimental data. The resulting g-factor and zero
field splitting were respectively determined to be
1.996 ± 0.013 and 2.88071 ± 0.00087 GHz. These
results agree well with the values from the literature[4] within the range of the error bars. It is worth mentioning that our spectrometer can sweep two parameters—magnetic field and spin excitation frequency—while standard ESR spectrometers can only
sweep the magnetic field. This wider range of parameter sweep enables us to refine the material parameters. It is especially powerful in investigating low
frequency spin transitions where the features ofhyperfine and quadrupole interactions appear.
4. Sensitivity and sensing volume
We estimate figures of merit of our ESR spectrometer: sensitivity and sensing volume. The sensing
volume is calculated by multiplying the sensing area
and the effective sensing height. The sensing area of
our magnetometer is limited to the loop structure of
47.2 μm2, and only the spins within a height of ~1 μm
NTT Technical Review

Vol. 17 No. 8 Aug. 2019can be detected [5]. Thus, the sensing volume is calculated to be ~0.05 pL. The sensitivity is estimated byanalyzing the noise of the magnetometer signal output. By measuring the noise for an integration time of
one second and converting the noise to the number of
spins using experimentally determined parameters,
we estimate the sensitivity to 400 spins/√Hz. Thisvalue is comparable to state-of-the-art ESR spectrometers using superconducting technologies [6, 7].
5. Future work
We plan to improve the sensitivity and the spatial
resolution of the spectrometer by refining the designof the superconducting flux qubit and the measurement system. We will also fabricate a flux qubit arrayto obtain spatial distribution of the materials. In thisarticle, we have only focused on solid-state spins.
However, the application area of our ESR spectrometer is not limited to such spins, and we are planning
to measure soft materials such as bio-related materials.
References[1]

H. Toida, Y. Matsuzaki, K. Kakuyanagi, X. Zhu, W. J. Munro, K.
Nemoto, H. Yamaguchi, and S. Saito, “Electron Paramagnetic
Resonance Spectroscopy Using a Direct Current-SQUID
Magnetometer Directly Coupled to an Electron Spin Ensemble,”Appl. Phys. Lett., Vol. 108, 052601, 2016.

14

Regular Articles

[2]

[3]

[4]
[5]

R. P. Budoyo, K. Kakuyanagi, H. Toida, Y. Matsuzaki, W. J. Munro,
H. Yamaguchi, and S. Saito, “Electron Paramagnetic Resonance
Spectroscopy of Er 3+ :Y 2 SiO 5 Using a Josephson Bifurcation
Amplifier: Observation of Hyperfine and Quadrupole Structures,”Phys. Rev. Materials, Vol. 2, 011403, 2018.
H. Toida, Y. Matsuzaki, K. Kakuyanagi, X. Zhu, W. J. Munro, H.
Yamaguchi, and S. Saito, “Electron Paramagnetic Resonance
Spectroscopy Using a Single Artificial Atom,” Commun. Phys., Vol.
2, 33, 2019.
J. H. N. Loubser and J. A.v. Wyk, “Electron Spin Resonance in the
Study of Diamond,” Rep. Prog. Phys., Vol. 41, No. 8, pp. 1201–1248,
1978.
D. Marcos, M. Wubs, J. M. Taylor, R. Aguado, M. D. Lukin, and A. S.

Hiraku Toida

[6]

[7]

Sørensen, “Coupling Nitrogen-vacancy Centers in Diamond to
Superconducting Flux Qubits,” Phys. Rev. Lett., Vol. 105, No. 21,
210501, 2010.
A. Bienfait, J. J. Pla, Y. Kubo, M. Stern, X. Zhou, C. C. Lo, C. D.Weis,
T. Schenkel, M. L. W. Thewalt, D. Vion, D. Esteve, B. Julsgaard, K.
Mølmer, J. J. L. Morton, and P. Bertet, “Reaching the Quantum Limitof Sensitivity in Electron Spin Resonance,” Nat. Nanotechnol., Vol.
11, No. 3, pp. 253–257, 2016.
S. Probst, A. Bienfait, P. Campagne-Ibarcq, J. J. Pla, B. Albanese, J. F.
Da Silva Barbosa, T. Schenkel, D. Vion, D. Esteve, K. Mølmer, J. J. L.
Morton, R. Heeres, and P. Bertet, “Inductive-detection Electron-spin
Resonance Spectroscopy with 65 Spins/√Hz Sensitivity,” Appl. Phys.
Lett., Vol. 111, No. 20, 202604, 2017.

Hiroshi Yamaguchi

Research Scientist, Superconducting Quantum
Circuit Research Group, Physical Science Laboratory, NTT Basic Research Laboratories.
He received a B.A., M.A., and Ph.D. in basic
science from the University of Tokyo in 2008,2010, and 2013. He joined NTT Basic ResearchLaboratories in 2013. Since then, his researchinterests have focused on interaction between aspin and a superconducting quantum device. He
is a member of the Physical Society of Japan(JPS) and the Japan Society of Applied Physics(JSAP).

Senior Distinguished Researcher and Group
Leader of Nanomechanics Research Group, NTT
Basic Research Laboratories.
He received a B.S. and M.S. in physics and a
Ph.D. in engineering from Osaka University in
1984, 1986, and 1993. He joined NTT Basic
Research Laboratories in 1986. His current interests are micro/nanomechanical devices using
semiconductor heterostructures. He has been aguest professor at Tohoku University, Miyagi,
since 2006. He is a fellow of the Institute of Physics and JSAP, and a member of JPS, APS, and theInstitute of Electrical and Electronics Engineers(IEEE).

Kosuke Kakuyanagi

Shiro Saito

Senior Research Scientist, Superconducting
Quantum Circuit Research Group, NTT Basic
Research Laboratories.
He received a B.S., M.S., and Ph.D. in sciencefrom Hokkaido University in 2000, 2002, and2005. He joined NTT Basic Research Laboratories in 2005 and has been studying superconducting qubits. He is currently engaged in an experimental study of physics on superconducting
quantum circuits. He is a member of JPS and
JSAP.

William J. Munro

Distinguished Researcher and Group Leader ofSuperconducting Quantum Circuit ResearchGroup, NTT Basic Research Laboratories.
He received a B.E., M.E., and Dr. Eng. inapplied physics from the University of Tokyo in
1995, 1997, and 2000. In 2000, he joined NTT
Basic Research Laboratories. He has since been
engaged in quantum information processing
using superconducting circuits. He was a guest
researcher at Delft University of Technology in
the Netherlands in 2005–2006. He has been aguest associate professor at Tokyo University of
Science since 2012. He was appointed a Distinguished Researcher of NTT in 2012. He received
the Young Scientist Award from JSAP in 2004.
He is a member of JPS and JSAP.

Senior Distinguished Researcher and Group
Leader of Theoretical Quantum Physics ResearchGroup, NTT Basic Research Laboratories.
He received a B.Sc in chemistry and an M.Sc
and D.Phil in physics from the University ofWaikato, New Zealand, in 1989, 1991, and 1995.
He was a research fellow at the University of
Queensland, Australia, from 1997 to 2000 before
becoming a permanent staff scientist at Hewlett
Packard Laboratories in Bristol, UK (2000–
2010). He joined NTT Basic Research Laboratories in 2010 as a research specialist before
becoming a Senior Distinguished Researcher in
2016. He is currently a visiting professor at the
National Institute of Informatics in Japan(2006–) and at the University of Queensland inAustralia (2012–). He was made a fellow of theInstitute of Physics (UK) in 2009, the American
Physical Society (APS) in 2013, and the OpticalSociety (OSA) in 2014.

NTT Technical Review

Vol. 17 No. 8 Aug. 201915

Global Standardization Activities

Activities of ITU-T Study Group 5(Environment, Climate Change andCircular Economy) and Discussion
Results
Naomichi Nakamura, Xiaoxi Zhang,and Yuichiro Okugawa
Abstract

The NTT Group participates in the development of international standards by the International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) with a view to protecting
telecommunication equipment from electromagnetic interference and lightning surges, assessing theimpact of information and communication technology on climate change, promoting a circular economy
conducive to sustainable development, enhancing the reliability of telecommunication services, andreducing the environmental load of the Group’s business activities. This article reports on the main discussion results of the ITU-T Study Group 5 meeting held in September 2018.
Keywords: ITU-T SG5, climate change, circular economy

1. Introduction

2. WP1 discussion results

The International Telecommunication Union Telecommunication Standardization Sector (ITU-T)
Study Group 5 (SG5) is responsible for studying
issues related to the environment, climate change,
and the circular economy and consists of two working parties (WPs) as shown in Fig. 1 [1]. WP1 studies
five Questions relating to protection of informationand communication technology (ICT) infrastructure
against electromagnetic surges, electromagnetic
compatibility (EMC), and human exposure to electro­
magnetic fields (EMFs). WP2 tackles three Questions
relating to energy efficiency, the circular economy,
and assessment of the environmental impact of ICT.
In this article, we report on the main results of dis­cussions in the SG5 meeting held in Geneva, Switzerland, September 11–21, 2018. An executive summaryof this meeting is posted on the ITU-T website [2].

WP1 addresses Questions 1 through 5. The contents of each question are explained in this section.

NTT Technical Review

Vol. 17 No. 8 Aug. 2019

2.1 Question 1
Question 1 concerns lightning strikes, earthing(grounding), and protection of communication systems against electromagnetic surges caused by powersystems. A proposal was made at this meeting to
expand the scope of a new Recommendation on protection of small-size telecommunication installations
with poor earthing conditions to include systems
without earthing ports or high-voltage direct current
systems. The meeting discussion included the idea ofapplying an isolation transformer (with limitations on
the length of the cable in the secondary winding anda requirement to indicate the danger of electric shock)to a system without earthing ports. Consent wasreached on a draft as Recommendation (K.134).
16

Global Standardization Activities

ITU-T SG5 (Environment, climate change and circular economy)
Q8 (Guides and terminology on environment and climate change)
WP1 (EMC, lightning protection, EMF)
Q1 (Protection of information and communication technology (ICT) infrastructurefrom electromagnetic surges)
Q2 (Equipment resistibility and protective components)
Q3 (Human exposure to electromagnetic fields (EMFs) from information andcommunication technologies (ICTs))
Q4 (Electromagnetic compatibility (EMC) issues arising in the telecommunication environment)
Q5 (Security and reliability of information and communication technology (ICT) systems
from electromagnetic and particle radiation)
WP2 (Environment, energy efficiency and the circular economy)
Q6 (Achieving energy efficiency and smart energy)
Q7 (Circular economy including e-waste)
Q9 (Climate change and assessment of information and communication technology (ICT)in the framework of the Sustainable Development Goals (SDGs)
Q: Question

Fig. 1. Questions and organization of ITU-T SG5.

2.2 Question 2
Question 2 concerns test methods and requirementsfor overvoltage protection devices such as varistors
and lightning arrestors. A comment on grounding of
direct current (DC) power lines was submitted. This
comment was related to existing Recommendation
revisions that had been discussed and given consent
at the previous meeting. They include K.20 and K.21,
which respectively specify overvoltage-related
requirements for systems installed in telecommunication buildings and those for systems installed in customer premises, and K.44, which specifies basic
requirements regarding overvoltages and overcurrents in telecommunication equipment. The meeting
participants agreed to issue a document on internal
DC powering interface surge testing factors as asupplement to K.20, K.21, and K.44.
NTT has been leading the development of K.spdsafe, which serves as guidance on safety relating to
the use of surge protective devices and surge protective components in customer buildings and accessnetworks. The meeting participants agreed to add tothis draft Recommendation information about safety
NTT Technical Review

Vol. 17 No. 8 Aug. 2019

for cases where high voltage occurs suddenly on telecommunication lines when the power system malfunctions, and for cases where an overvoltage occurs
on internal line ports. This draft Recommendation
will be consented to when International Electrotechnical Commission (IEC) Technical Committee 108
arrives at a basic understanding of it.
The participants also discussed K.135, a new Recommendation on technical parameters for residualcurrent-operated protective devices with an automatic
reclosing feature for telecom applications, and theyreached consent on it with some editorial changes.
2.3 Question 3
Question 3 concerns management, measurement,
and guidelines regarding human exposure to EMFs
from telecommunication equipment such as wirelessaccess systems. NTT DOCOMO and the National
Institute of Information and Communications Technology, both based in Japan, submitted evaluation
data on human exposure to EMFs in the vicinity of amaintenance hole (manhole)-installed base station. It
was found at the meeting that such data had not
17

Global Standardization Activities

previously existed and that the data were very usefulfor member countries. The data were added to K.91
(Guidance for assessment and monitoring of human
exposure to radio frequency EMFs), an existing Recommendation, as Appendix VIII. Four version-one
draft Recommendations were also discussed andagreed to, including K.workers, which concerns theassessment and management of restrictions regarding
exposure of wireless equipment workers to EMFs.
2.4 Question 4
Question 4 pertains to EMC-related requirements
for new telecommunication equipment, telecommunication services, and wireless systems. The meetingmembers discussed two new Recommendations(K.136 and K.137) related to EMC-related requirements for wireless and wireline equipment, specified
their scopes of application, reviewed the compatibility of these Recommendations with existing standards, and consented to their final drafts. NTT proposed adding specifications on acceptable values for
conducted interference waves below 150 kHz to
K.123, an existing Recommendation on EMC-related
requirements for electrical equipment within a telecommunication building. This proposal was based on
NTT technical requirements [3], which NTT revisedin fiscal year 2018. Consensus was reached on that
proposal. The final draft was discussed and consented
at the next meeting, which was held in May 2019.
2.5 Question 5
Question 5 concerns soft errors in telecommunication equipment caused by particle radiation, andelectromagnetic security. Japan proposed the fourth
version of a new draft Recommendation on methods
for estimating quality from soft error test results, andguidelines for application of these methods. The
meeting members discussed definitions of terms andspecification grounds and consented to the final draftfor K.138. Similarly, consent was reached on the final
draft for a new Recommendation (K.139) on reliability requirements for telecommunication equipment tocounter soft errors, which Japan was proposing tostudy, after minor revisions.
In the coming years, WP1 will develop new Recommendations on requirements for measures against
soft errors in semiconductor devices used in telecommunication equipment, and will revise K.78, an existing Recommendation on protection of telecommunication equipment from high-altitude electromagnetic
pulses, which has recently been the subject of considerable discussion, by incorporating the latest IEC
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Vol. 17 No. 8 Aug. 2019

standards and study results.
3. WP2 discussion results
WP2 deals with Questions 6, 7, and 9, the topics ofwhich are explained here.
3.1 Question 6
Question 6 pertains to the energy efficiency of telecommunication equipment and datacenters. It was
proposed to include main battery technologies andcharacteristics, a selection of battery technologies
suitable for individual applications, and battery evaluation and test methods in L.1220, an existing Recommendation on energy storage technology, as Part
2. Part 2 will be based on Part 1 of L.1220, which
describes general methods for selecting and evaluating storage system technology. The meeting members
consented to the final draft (L.1221). They also discussed the criteria and methods for measuring energy
efficiency of functional components such as virtual
network functions and network functions virtualization (NFV) infrastructure in an NFV environment inconnection with L.mmNFV, a new Recommendationon the measurement method for measuring the energy
efficiency of NFV. The members consented to thefinal draft (L.1361).
3.2 Question 7
Question 7 concerns the circular economy including e-waste (electrical and electronic devices thathave been disposed of). The Connect 2020 Agenda*
is aimed at achieving a 50% reduction in e-waste by
2020. It was proposed to create a guidance documentthat specifies three steps: (1) creation of a comprehensive e-waste inventory; (2) development of a sustainable e-waste management system; and (3) introduction of support measures to promote the use of
said management system. The meeting members consented to the final draft (L.1031). They also studied
L.CEM, a new Recommendation on criteria for evaluating the environmental impact of mobile phones.
Criteria for this assessment, which takes into consideration the entire life cycle of a product, from design
through production and use to end of life, and is basedon the contents of L.Suppl.32 (supplementary document) and UL Standards (electric product safety
standards in the US), such as UL110. The meetingmembers consented to the final draft (L.1015).
*

Connect 2020 Agenda defines ITU’s policies on ICT-related activities up to 2020.

18

Global Standardization Activities

3.3 Question 9
Question 9 pertains to methods for assessing thesustainability impacts of ICT in order to promote theUnited Nations Sustainable Development Goals.
Both the assessment procedure part and the futureforecast part of L.MAE, a new Recommendation on
methodology for assessing the environmental impactof the ICT sector, were revised at the meeting in order
to incorporate received comments, and agreement
was reached on the final draft (L.1450).
A proposal was made and accepted to create, as asupplementary document to this Recommendation,
greenhouse gas (GHG) emissions trajectories for the
ICT sector compatible with the United Nations
Framework Convention on Climate Change Paris
Agreement. This supplementary document will be
developed in collaboration with the Global e-Sustainability Initiative. The collaboration will be extended
to include the Science Based Targets Initiative.
Discussions on L.MAAP, a new Recommendation
on methods for assessing the positive impact of ICT
on sector level, have been ongoing since 2017. The
currently proposed method is a bottom-up method. It
aggregates GHG emissions from each component tobe assessed. At this meeting, NTT proposed a topdown method to assess the impact of ICT use on theenvironment and economy based on an Input-output
Table, which represents nation-level inter-industry

Naomichi Nakamura

Senior Research Engineer, EMC Technology
Group, Environmental Technology and Management Project, NTT Network Technology Laboratories.
He received a B.E. in physics from Nihon
University, Tokyo, in 2004 and an M.E. in nanoscience and nanoengineering from Waseda University, Tokyo, in 2006. He joined NTT Energy
and Environment Systems Laboratories in 2006
and studied EMC technology for telecommunication. He has been researching and developing
methods of lightning protection and grounding
for telecommunication systems. He is a memberof the Institute of Electronics, Information andCommunication Engineers (IEICE).

trade. The meeting members agreed to include NTT’s
proposal in the draft Recommendation.
4. Conclusion
We have introduced the latest standardization
activities of ITU-T SG5. Communication technology
is advancing on a daily basis, as is manifested by the
emergence of 5G (fifth-generation mobile communications), the Internet of Things, and virtualization.
We will promote timely standardization in order toenable rapid response to changes in the environment
surrounding telecommunication facilities and to contribute to enhancing the quality and reliability oftelecommunication services while reducing theirenvironmental load.
References
[1]
[2]

[3]

ITU-T SG5 Study Group Structure, https://www.itu.int/net4/ITU-T/
lists/sgstructure.aspx?Group=5&Period=16
Executive Summary of the ITU-T Study Group 5 Meeting “Environment, Climate Change and Circular Economy” (Geneva, 11–21 September 2018).
https://www.itu.int/en/ITU-T/studygroups/2017-2020/05/Pages/
exec-sum-201809.aspx
Website of NTT, Technical Requirements, http://www.ntt.co.jp/
ontime/e/policy/tr/

Yuichiro Okugawa

Senior Research Engineer, EMC Technology
Group, Environmental Technology and Management Project, NTT Network Technology Laboratories.
He received a B.E. and M.E. in electrical engineering from Tokyo University of Science in2002 and 2004. He joined NTT Energy and Environment Systems Laboratories in 2004 andstudied EMC technology for telecommunication.
He is currently studying soft error test methods
and high-altitude electromagnetic pulse attacks
on telecommunication equipment.

Xiaoxi Zhang

Research Engineer, Environmental Assessment
Technology Group, Environmental Technology
and Management Project, NTT Network Technology Laboratories.
She received a B.S. and M.S. in social engineering from Tokyo Institute of Technology in2007 and 2009. Since joining NTT in 2009, she
has been engaged in research on risk-based management of telecommunication infrastructures.
She is currently researching methods of assessing environmental impacts of ICT use. She is amember of IEICE.

NTT Technical Review

Vol. 17 No. 8 Aug. 201919

Practical Field Information about
Telecommunication Technologies
Practical Field Information about Telecommunication Technologies

Countermeasures against Insect
Damage to User Equipment—
Repellent Sheet and Repellent SpiralTechnical Assistance and Support Center, NTT EAST
Abstract

Telecommunication equipment can malfunction if it is damaged by insects. It is therefore necessary todevelop measures to prevent such damage. This article presents examples of the damage that can occur
when cockroaches nest inside equipment and introduces two products designed to stop them fromaccessing the equipment. This is the fifty-third article in a series on telecommunication technologies.
Keywords: insect damage, repellent, cockroach

1. Introduction
Telecommunication equipment is installed in various environments, and it therefore must coexist withany creatures living there. Equipment installed outdoors or at a customer’s premises is usually exposed
to living things, and that exposure often leads to damage to the equipment. This report introduces the characteristic damage that occurs to telephones and communication equipment such as home gateways caused
by insects such as cockroaches—about which theTechnical Assistance and Support Center has received
many inquiries from all over the country—anddescribes our countermeasures against such damage.
2. Characteristics of damage due to cockroaches
If cockroaches invade and nest inside communication equipment such as a telephone and home gateway at a customer’s premises, they may chew thesubstrate and wiring, or their habitation may cause a
malfunction such as substrate shorting due to theirexcrement (Photo 1). In the field, although the equipment can be repaired or replaced, if the surrounding
environment does not change, it is likely that the
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Vol. 17 No. 8 Aug. 2019

cockroaches will crawl into and nest in repaired or
new equipment again and again, and the malfunctions
will keep reoccurring.
The results of investigations into the cause of malfunctions that occurred due to cockroaches revealed
that the intruding cockroaches are 3 to 12 mm inlength. Their brown body and pale back led to theconclusion that they are the species called German
cockroaches (Blattella germanica) [1]. The German
cockroach inhabits all regions of Japan and prefers
warm and dark places; accordingly, it is often foundin air-conditioned environments such as restaurants.
Since the interior of communication equipment isalways warm and dark, it is considered a convenientenvironment for the cockroaches to nest in.
Previous measures against cockroach damage
involved asking customers to remove the cockroaches
and block places that serve as cockroach entrances tocommunication devices. However, such countermeasures were difficult to implement since radical extermination was difficult, and not all entry points to theequipment could be closed off.

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Practical Field Information about Telecommunication Technologies

Photo 1. Cockroaches nesting inside a telephone (imagesof cockroaches are blurred).

Photo 3. Inside a core-wire housing containing broken
fibers (images of ants are blurred).

Photo 2. Repellent tape.

Photo 4. Interior of metal terminal box in which core-wireinsulation is broken.

3. New countermeasures based on
insect repellent

other, and that contact caused insulation failure(Photo 4). Implementing measures using repellent
tape makes it possible to prevent ants nesting in optical closures and metal terminal boxes (Photo 5).
As a result of the examinations described above, we
devised a repellent sheet and a repellent spiral—bothof which use the same repellent agent—as a new
countermeasure against cockroach damage (Photo 6).

In the meantime, the Technical Assistance and Support Center has been examining damage to accessequipment caused by insects such as ants. We havealso been collaborating with pharmaceutical companies to promote measures to prevent such damage.
These measures include producing a type of tape that
contains a repellent composed primarily of a pyrethroid*1, which has a repellent effect against insects(Photo 2).
Damage by ants to access equipment was mainly
caused by ants nesting in the optical closures of overhead equipment. The ants often chewed throughoptical-fiber core wires inside core-wire housings,
disconnecting them (Photo 3). Moreover, inside
metal terminal boxes, the ants chewed the outer
sheaths of the core wires. The effect of formic acid*2
caused the core wires to come into contact with each
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*1 Pyrethroid: A generic term for substances related to pyrethrins,
which are the active ingredient of the flower pyrethrum chrysanthemum. Insects are repelled from surfaces treated with a pyrethroid because when it penetrates their skin and mouth, it acts on
their nerves in a manner that numbs them. Pyrethroid-containing
substances have no effect if they enter the body of warm-blooded
animals such as mammals and birds because they are quickly
broken down and excreted. Moreover, pyrethroids are not affected by moisture or water droplets, so their efficacy does not decrease if they get wet.
*2 Formic acid: Strongly acidic component secreted by ants when
they lay markings to attract companions or when they attack enemies.

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Practical Field Information about Telecommunication Technologies

Optical closure

Metal terminal box

Photo 5. Installation of repellent tape.

Repellent sheet

Repellent spiral

Photo 6. Cockroach prevention measures.

The repellent sheet is an A4-size sheet that has arepellent coated on its surface. The sheet is placed
under communication equipment to stop cockroaches
entering from the bottom of the equipment. The
repellent sheet has a three-layer structure consistingof repellent, polyester sheet (semi-transparent), andnon-slip coating. As well as having a repellent effect,
the non-slip coating prevents movement of the sheet
while the equipment is in use.
The repellent spiral is made of a polyester material,with repellent agent applied to the inner and outersurfaces of the spiral. This prevents insects frominvading communication equipment via electricalcables. The spiral has an inner diameter of 12 mm anda length of about 30 cm. It is simply wrapped aroundpower supply cords, local area network cables, andthe like.
The repellent sheet can simply be placed under themain units of communication equipment, and therepellent spiral can simply be wrapped around power
supply cords and cables by workers in a quick andeasy manner (Photo 7). Moreover, the period during
which the repellent effect of these countermeasureproducts lasts is about 10 years (for equipment
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installed in dark places). Although it is necessary to
avoid exposure of these products to direct sunlightsince ultraviolet (UV) rays reduce the repellent effect,
we know that about 80% of the insect-repellent effectis maintained after two years if the usage environment is under UV light at the level produced byindoor fluorescent light.
4. Verification of effectivenessof countermeasures
We conducted the following experiment in collaboration with a pharmaceutical company in order toevaluate the repellent effect of the repellent sheet andthe repellent spiral in relation to cockroaches. A
phone fitted with both the sheet and the spiral and aphone without either of them were set up in a largecase used for the experiment. About 50 cockroaches
were left in the test case for six days, after which we
checked whether any cockroaches were nesting ineither of the phones. The result of this experiment
was that after six days, cockroaches had invaded andnested in the phone without the repellent products; incontrast, no cockroaches had nested inside the phone22

Practical Field Information about Telecommunication Technologies

TelephoneHome gateway

Photo 7. Installation image of countermeasure products.

fitted with the products.
We also implemented the countermeasures in thefollowing example of an on-site application. In thisexample, cockroaches had intruded into a telephone
installed in a restaurant, and the phone had repeatedly
malfunctioned due to cockroach damage.
At the restaurant, there were regular incidents of thephone malfunctioning (about once every threemonths) and not being able to be used. The phone was
replaced after each incident. The malfunctions werelater found to be due to cockroach damage. Consequently, the Technical Assistance and Support Center
received a request to conduct research on biologicaldamage to equipment and countermeasures against
such damage. We then decided to implement countermeasures at the restaurant using the repellent sheet
and repellent spiral. First, to prevent cockroaches getting into the phone, we installed the repellent sheet
under the phone and attached the repellent spiral tothe cables connected to the phone. At this writing, it
has been about six months since the countermeasures
were implemented, and the phone has not malfunctioned since then. We thus believe that it will be possible to prevent cockroaches nesting inside phones byapplying these countermeasures in the future. We are
currently working on the commercialization of these

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countermeasures as products that can also be purchased by companies outside the NTT Group that
construct telecommunication facilities.
5. Concluding remarks
This report focused on biological damage to user
equipment and specifically introduced measures toprevent damage caused by cockroaches. These countermeasures are easy to implement and are expected
to help our customers reduce such damage in thefield. The Technical Assistance and Support Center,
including our predecessor the Technical Cooperation
Department, has provided on-site assistance throughtechnical cooperation activities for over 50 years. We
will continue to apply the knowledge and experience
we have accumulated so far as well as to develop newtechnologies in our efforts to reduce the number ofmalfunctions that occur and improve the reliability ofcommunication equipment.
Reference[1]“Encyclopedia of Insects I,” Sekai Bunka Publishing Inc., 2004 (inJapanese).

23External Awards
International Standard Development Award
Winner: Noboru Harada, NTT Media Intelligence Laboratories
Date: April 25, 2019
Organization: Information Technology Standards Commission ofJapan (ITSCJ), Information Processing Society of Japan (IPSJ)
For his contribution to the development of international standards
on lossless audio coding by the International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC).

Contribution Award for Standardization
Winner: Shinya Shimizu, NTT Media Intelligence Laboratories
Date: May 21, 2019
Organization: ITSCJ, IPSJ
For his contribution to standardization activities in ISO/IEC Joint
Technical Committee 1/Subcommittee 29/Working Group 11.

Papers Published in Technical Journals andConference Proceedings
One-way Transfer of Quantum States via Decoherence
Y. Matsuzaki, V. M. Bastidas, Y. Takeuchi, W. J. Munro, and S.
Saito
Proc. of the 20th Anniversary of Superconductiong Qubits, P-61,
Tsukuba, Ibaraki, Japan, May 2019.
Quantum state transfer is an important technique in quantum information processing. The standard way to transfer the quantum state is
to use a unitary evolution and/or a measurement feedforward operation. A sequential implementation of SWAP gates can transfer thequantum states from the initial site to the target site. Implementationsof control-phase gate and subsequent measurement feed-forwards
can perform quantum teleportation. Unitary evolution due to the flipflop interaction induces oscillations of quantum states between sites,
and an appropriate turn on/off of the interaction can implement aquantum state transfer. However, such approaches need to switch on/
off the interaction between quantum systems with accurate timing,
which could induce time jittering error. Here, we propose an alternative way to implement a directional transfer of the quantum state via
decoherence from the tailored environment.

Kirari! for Arena: Real-time Remote Reproduction of
4-directional Views with Depth Perception
J. Nagao, H. Miyashita, T. Sano, K. Hasegawa, and T. Isaka
Journal of the Imaging Society of Japan, Vol. 58, No. 3, pp. 306–
315, June 2019.
This paper describes the “Kirari! for Arena” system, which is an
integral combination of NTT’s immersive telepresence technology“Kirari!”. This system transports events such as sports and entertainment to remote locations in real time and reproduces the scene in four
directions with depth perception. At the capture site, it shoots videos
from four directions, scans the positions of objects, performs image
extraction and tracking of objects, and transmits the information to

NTT Technical Review

Vol. 17 No. 8 Aug. 2019the remote locations in real time. At the reproduction site, it transforms the videos to add depth perception and projects them to a special four-sided display device.

Word-based Japanese Typed Dependency Parsing with
Grammatical Function Analysis
T. Tanaka and M. Nagata
Journal of Natural Language Processing, Vol. 26, No. 2, pp. 441–
481, June 2019.
We present a novel scheme for word-based Japanese typed dependency parsing which integrates syntactic structure analysis and grammatical function analysis such as predicate-argument structure analysis. Compared to bunsetsu-based dependency parsing, which is predominantly used in Japanese NLP, it provides a natural way of
extracting syntactic constituents. This makes it possible to jointly
decide dependency and predicate-argument structure, which is usually implemented as two separate steps. By using grammatical functions as dependency types, we can obtain the detailed syntactic
information from parsing results, while keeping the converted bunsetsu-based dependency accuracy as high as CaboCha, one of thestate-of-the-art dependency parsers.

Sound Event Localization and Detection Using FOA
Domain Spatial Augmentation
L. Mazzon, M. Yasuda, Y. Koizumi, and N. Harada
The Fifth Edition of the IEEE AASP Challenge on Detection andClassification of Acoustic Scenes and Events (DCASE 2019 Challenge), New York, USA, Mar.–June 2019.
This technical report describes the system used in the DCASE
2019 Task 3: Sound Event Localization and Detection challenge. The

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Papers Published in Technical Journals and Conference Proceedings

system consists of a convolutional recurrent neural network (CRNN)
reinforced by a ResNet structure. A two-stage training strategy withlabel masking is adopted. The main advancement of the proposed
method is a data augmentation method based on rotation in the firstorder Ambisonics (FOA) domain. The proposed spatial augmentation
enables us to augment direction of arrival (DOA) labels without losing physical relationships between steering vectors and observations.
Evaluation results of the development dataset show that even though
the proposed method did not use any ensemble method in thisexperiment, (i) the proposed method outperformed a state-of-the-art
system published before the submission deadline and (ii) the DOA
error has significantly decreased: 2:73° better than the state-of-the-art
system.

An Experimental Demonstration of Secure Quantum Sensing
P. Yin, Y. Takeuchi, W. Zhang, Y. Matsuzaki, and G. Chen
Gordon Research Conference, Hong Kong, China, June 2019.
In a previous work, we theoretically proposed a secure delegatedquantum sensing protocol. In this presentation, we give results of a
proof-of-principle experiment of our delegated quantum sensing
protocol. From the experiment, we have confirmed that our protocol
is secure.

Quantum Computational Universality of HypergraphStates with Pauli-X and Z Basis Measurements
Y. Takeuchi, T. Morimae, and M. Hayashi
Quantum Information and String Theory 2019, Kyoto, Japan,
May/June 2019.
Measurement-based quantum computing is one of the most promising quantum computing models. Although various universal
resource states have been proposed so far, it was open whether only
two Pauli bases are enough for both universal measurement-based
quantum computing and its verification. In this talk, we construct auniversal hypergraph state that only requires adaptive Pauli X andZ-basis measurements for universal measurement-based quantum

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Vol. 17 No. 8 Aug. 2019

computing. We also show that universal measurement-based quantum computing on our hypergraph state can be verified in polynomial time using only non-adaptive X and Z-basis measurements.

A Pilot Study on Consumer IoT Device Vulnerability Disclosure and Patch Release in Japan and the United States
A. Nakajima, T. Watanabe, E. Shioji, M. Akiyama, and M. Woo
The 14th ACM ASIA Conference on Information, Computer andCommunications Security (ACM ASIACCS 2019), Auckland, New
Zealand, July 2019.
With our ever-increasing dependence on computers, many governments around the world have started to investigate strengthening theregulations on vulnerabilities and their lifecycle management.
Although many previous works have studied this problem space formainstream software packages and web applications, relatively few
have studied this for consumer IoT devices. As a first step towards
filling this void, this paper presents a pilot study on the vulnerability
disclosures and patch release behaviors related to three prominent
consumer IoT vendors in Japan and three in the United States. The
goals of this study include (i) characterizing trends and risks using
accurate data that spans a long period, and (ii) identifying problems,
challenges, and potential approaches for future studies of this problem space. To this end, we collected all published vulnerabilities andtheir patches for the consumer IoT products by these vendors
between 2006 and 2017; then, we analyzed them from multiple perspectives such as the timing of patch releases with respect to disclosures and exploits as well as the severity of the vulnerabilities. Our
work has uncovered several important findings that may informfuture studies. These findings include (i) a stark contrast in the vulnerability disclosures in the two included countries, (ii) multiple
alarming practices by the included vendors that may pose significant
risks of 1-day exploits, and (iii) challenges in data collection including crawling automation and long-term data availability. For each ofthese findings, we also provide discussions on its consequences and/or potential migrations or solutions.

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