NILIM News Letter

No. 66
2 019

Implementation of coastline monitoring technology utilizing satellite images forRiver Department, Coast Divisioncontinuous wide-area diagnosis of coastal erosion
In order to allow early adoption of coastal erosion control
measures, we are implementing a system to perform continuous
wide-area diagnosis of any coastline changes due to coastal
erosion, via the use of satellite images.

There is currently demand for technologies or systems to continuously andfrequently monitor changes caused by coastal erosion in wide areas of theJapanese coastline, which has a total length of over 30,000 km, without theneed for a large workforce or great expense. One technology that could
potentially facilitate this is SAR (Synthetic Aperture Radar: a sensor that emits
microwaves toward a target and then receives the backscattered signals), which
is cheaper than optical satellite imaging and is not affected by the weather,thus enabling surveillance both during day and night. NILIM plans to start
monitoring the coastline (initially for a length of around 400 km) in FY2019,building a system that employs SAR satellite imagery monitoring technology
developed as part of river erosion control technology R&D. Besides publishingthese results every year so that it is easy to understand the state of progressionof coastal erosion, we also plan to use the results when considering methods ofevaluating the effects of countermeasure and for clarification of the coastal
erosion mechanism.
Up until now, we have been able to verify that, as long as factors such as
photographing angle and sediment are satisfactory, it is possible to sample thecoastline from satellite images with sufficient accuracy to grasp long-term
regression tendencies, as shown in the pictures. From here on, we shallcontinue providing systems necessary for monitoring, while also improving
sampling methods so that coastline sampling can be performed even withimages under worse conditions. We are also considering lending such systems
to allow coastal inspectors to perform monitoring by themselves, if they sowish.

Murozumi coast

Comparison between sampled coastline (in blue) andcoastline actually measured (in red)
(Numbers show mean error in cross-shore direction)

Details ☛ Ministry of Land, Infrastructure, Transport and Tourism
homepage: “River erosion control technology R&D”
http://www.mlit.go.jp/river/gijutsu/kaigankadai/pdf/h28_report_ tajima.pdf

Debris flow detection sensor utilizing AI

Sabo Department, Sabo Planning Division
15 cm

A debris flow detection sensor utilizing AI was developed incollaboration with the National Institute of Advanced Industrial
Science and Technology (AIST). It is hoped that this will improvedetection accuracy and reduce cost.
With the wire sensors frequently used for debris flow detection, flow is
detected when the wire installed across a valley is cut by passing debris.
However, one major issue with this system is that debris flow cannot be
detected until the wire is replaced, after having been cut once. Although there
are also vibration sensors that detect debris flow from vibration, it is difficult
with such sensors to properly carry out adjustment in advance to the level ofvibration to be regarded as debris flow, and there is also the possibility oferroneously detecting vibrations other than from debris flow, which is why they
are not widely used.
With this in mind, in 2016 NILIM and AIST began collaborative research todevelop a new debris flow detection sensor utilizing AI and IoT. This sensor can
detect debris flow by having its AI learn the peculiarities of vibrations caused bydebris. After installing a prototype sensor in Sakurajima, Kagoshima, where
there is frequent debris flow, and performing continuous inspections based on
the AI’s machine learning, it became possible to detect debris flow with highaccuracy. Also, the sensor body uses fine processing technology with asemiconductor silicon board, which compared with conventional sensors ismuch smaller, less expensive and easier to install, making it possible to install
multiple sensors in the same location. Thus, by performing detection with

Fuji coast

Solar panel

Antenna
30 cm
Battery storage
Overview of the sensor prototype

multiple sensors instead of a single one, we can expect improved detection
accuracy and ensure a fail-safe system in case of sensors being damaged or washedaway. Going forwards, we are aiming to put the sensor to practical use, and we plan
to inspect its real-time detection accuracy using debris flow software, as well as its
durability under the harsh natural environments of mountain streams.
In the future, if this new sensor becomes widely accepted, we can look forward to
precise assessment of the conditions of sediment disasters, leading to prompt
provision of surveillance systems and evacuation measures.

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Report on research with Indonesia in field of road engineering

Planning and Research Administration Department, International Research Division

Here we introduce a journey that we have been taking for around10 years in collaborative research performed with the Indonesian
Institute of Road Engineering (IRE).
Based on the needs of the Institute of Road Engineering (IRE) in the Republic ofIndonesia, NILIM signed a memorandum of understanding in 2009, and sincethen has conducted collaborative research also involving the Public Works
Research Institute. The memorandum revised in 2014 targeted six fields –“roadside stations”, “traffic volume measurement”, “traffic safety”, “roadenvironment”, “paving”, and “tunnels and underground structures” – and it has
functioned to allow researchers of both countries to attain broader knowledge
via inspection of construction sites or infrastructure facilities, in addition tofacilitating discussions in collaborative workshops.
The main results obtained are presented below.
[Roadside stations] In Indonesia there is a shortage of rest stop areas for drivers.
Moreover, in order to address the expanding regional disparities that follow thecountry’s economical growth, regional development of rural areas has become apressing matter. As one possible solution for such issues, we have performed
collaborative investigation and research, as well as written guidelines, aiming tobuild facilities akin to Japan’s roadside stations.
[Traffic volume measurement] In Indonesia, although underground sensors
were common in traffic volume measurement, damage to devices was frequent,and inaccurate measurement of two-wheeled vehicles was also an issue. As asolution, research was conducted regarding the possibility of improving theWorkshopOn-site inspection

measurement accuracy of traffic volume based on image analysis, which made it
possible to obtain knowledge regarding the best methods for installing
cameras, for example.
Aside from this, we have also conducted repeated research and createdguidelines for paving technologies using “Asbuton”, a natural asphalt producedin Indonesia, and for supplementary construction methods of tunnels in poor
quality bedrock. After the revision of the agreement planned for this year, we
expect to begin tackling new issues while also contributing to reinforcement of
the cooperation between our two countries.

Details ☛ NILIM website: “International activities”
http://www.mlit.go.jp/river/gijutsu/kaigankadai/pdf/h28_report_ tajima.pdf“Cardboard bridge building contest” - an outreach activity that has lasted aPlanning and Research Administration Department, Planning Division
quarter-century
We held the 25th “Cardboard bridge building contest”. This time,
we implemented new initiatives celebrating the quarter-century
history of the contest.
NILIM has been holding the “Cardboard bridge building contest” for elementary
school children from 4th and 5th grades in the city of Tsukuba since 1994, withthe objective of teaching about the importance of civil engineering infrastructure
in our daily lives through handicrafts.
Although the conditions for project creation are strict, requiring two sheets (B3size) of handicraft cardboard to be used in making a 30 cm bridge that can
support 1 kg of weight, the contest normally sees the participation of over 700
children (around 20% of the eligible students in the city).
Upon inviting applications, many schools set the project as a summer holiday
assignment with the cooperation of Tsukuba city’s Board of Education. Each year
all submitted projects are exhibited on Civil Engineer’s Day, when the instituteopens its doors to the public, and we believe this continuous effort held for 25
years contributes to the strong interest shown by children and to the large
number of applications received.
Up until now this contest has seen around 8,000 project applications,handcrafted by more than 10,000 children. This time, two new initiatives wereintroduced to celebrate the quarter-century history of the contest and to express

our gratitude to all participants.
The first of these is the summer break course “Let’s build a bridge”, aimed atchildren. This course was composed of both theory and practical lessons frompaper craft experts regarding the basics of paper modeling (how to cut, fold andpaste paper), together with researchers from the NILIM introducing topics on
bridge building, including practical experiments.
The 60-student capacity was filled immediately after applications wereopened, and many of those who took the course also participated in thecontest.
The second initiative was a popularity poll held among visitors to theexhibition of all the submitted projects on Civil Engineer’s Day, when theinstitute opens its doors to the public. As a result of the poll, in addition to theprizes handed out based on the decisions of the panel (18 projects were given
awards, including a Grand Prize and a Structure Design Prize), the project withthe largest number of votes also received the Civil Engineer’s Day 2018 Prize”.
Children could be seen with their eyes fixated on the exhibits, trying to discovereach project’s strengths in order to vote in the poll, which led to the selection ofan outstanding project with a different flavor than those chosen by the panel ofexperts.
The “Cardboard bridge building contest” is formed through the collaborationof many children and all the people involved. We hope the children who
participated in this contest will continue to be involved in infrastructure facilities
projects in the next generation, and we would like to continue making efforts tofurther develop the contest so that it can last for 50, 100, or many more years tocome.

Details ☛ NILIM website: “Cardboard bridge building contest”
http://www.nilim.go.jp/lab/bbg/event/buridgecontest/2018/2018bridge.html

Projects that received awards (Grand Prize and Civil Engineer’s Day 2018 Prize)

2

“The 19th Tokyo Bay Symposium: New technologies & approaches to improve theCoastal, Marine and Disaster Prevention Department Marine Environment and Emergency Management Division
coastal area environment”
The 19th edition of this event was held on October 18, 2018 at the
Osanbashi International Passenger Terminal of Yokohama Port.
The Tokyo Bay Symposium is held every year with the aim of fostering thoughtboth for a better Tokyo Bay environment and a better future, gathering the most
up-to-date knowledge from research institutions, private companies, and NPOs,
and divulging such information to a wide range of people.
This time the event’s themes were “new technologies” (such as IT) that could be
employed to improve the coastal area environment, and “new approaches” thatwill become key in thinking about environment improvement going forwards,
and there were a total of 273 participants. Lectures were given by nine different
speakers on the topics of blue carbon (carbon captured by living organisms inoceans), environmental DNA, image analysis, artificial satellites, parasitic worms,
matters related to the Tokyo Olympic and Paralympic Games, soil originatedinland, use of IT in the fishing industry, SDGs for coastal areas, and other new
technologies and approaches. A poster session was organized during theinterval, in which students, researchers, enterprises, administrative bodies, andNPOs, etc. carried out lively exchanges of ideas about posters related to research,

A lecture at Tokyo Bay Symposium

technology, and activities for the revitalization of Tokyo Bay.
Also, on October 20 and 21, in order to generate greater interest in Tokyo Bay
the Tokyo Bay Great Thanks Festival was held by The Public-Private Cooperation
Forum for Tokyo Bay Restoration in places such as the Yokohama Red Brick
Warehouse, under the theme “Let’s start doing good actions for the ocean!” Thefestival was attended by 105,000 visitors, including many families.
As many visitors were able to enjoy discovering and experiencing the appeal
and blessings of Tokyo Bay through the Tokyo Bay Symposium and the Tokyo Bay
Great Thanks Festival, we believe this provided a great opportunity for actions
that will improve the Tokyo Bay environment. We hope to continue our efforts togenerate greater interest in the Tokyo Bay environment in the future.

Details ☛ NILIM website: “Tokyo Bay Symposium”
http://www.ysk.nilim.go.jp/kakubu/engan/kaiyou/kenkyu/tokyobay-sympo.html
Details ☛ Tokyo Bay Great Thanks Festival website:
http://tbsaisei.com/fes/

Tokyo Bay Great Thanks Festival(Source: Tokyo Bay Great Thanks Festival Board Secretariat)“Compact and smart urban planning” lecture held at the 16th Environmental
Urban Planning Department, Urban Planning Division
Research Symposium
We delivered a lecture at the 16th Environmental Research
Symposium regarding research to achieve urban sustainability
currently being carried out at NILIM.

In Japan, whose society is rushing into a fully-fledged population decline,
making cities that have spread due to low population density more compact(consolidating urban structures) has become an urgent matter. On the other
hand, as urban planning based on the provision of efficient urban services(making the city smarter) that make use of rapidly developing ICT becomes morefeasible, the fusion of compactness and smartness can be promising as a way ofmaking sustainable cities a reality.
As one of the efforts in the Environmental Research Promotion Headquarters
activities, NILIM participated in the 16th Environmental Research Symposium, an
event that facilitates the exchange of information on research results between
national research institutes and other bodies involved in environmental research.
This event (held on November 13) adopted the title “Smart Society andEnvironment: Aiming for Consideration of Both Rich Life and Environment”, andwe delivered a lecture on the related research that we are currently conducting.
In the lecture, as an example of studies on urban compactness, we introduced
on-going research on urban planning, such as for provision of livelihood services
and redevelopment of districts based on the results of objectively measuring thecity’s future image (future population, cost of infrastructure, etc.) at a districtlevel.
Also, as an example of studies of urban smartness, we introduced survey
technology that makes use of mobile phones to ascertain the flow of people

within a city, as well as survey technology to three-dimensionally grasp a city’s
green areas via airborne laser measurements.
Attended by various researchers and government officials, as well as othercitizens, the event was a good opportunity to fully introduce NILIM and to gather
opinions, via the lectures and other means.

Details ☛ The website of the 16th Environmental Research Symposium
http://kankyorenrakukai.org/symposium_16/index.html
Details ☛ NILIM website:“Environmental Research Promotion Headquarters”
http://www.nilim.go.jp/japanese/organization/k_honbu/indexkankyou.htm

A lecture at the Environmental Research Symposium3

● Publications (research achievements)
Download here

http://www.nilim.go.jp/lab/bcg/siryou/index.htm

NILIM Materials
Department/Division

Title

No.

1011 B-DASH Project No. 19 Guidelines for introducing an advanced reclaimed water system using ultrafiltration

Wastewater and Sludge
Management Division1012 B-DASH Project No. 20 Guideline for Introducing an Efficient Survey Technology for Force Mains Damaged by Sulfuric

Wastewater System Division1014 Materials on technologies concerning the use of greening with native wild grass1015 Collaborative research concerning the application to traffic planning of statistical data on people movement based

Landscape and Ecology Division

membranes and ultraviolet disinfection (Proposal)
Acid Corrosion (Proposal)

on operational data of mobile phone base stations
1016 Organization of the state of reconstruction/restoration since the Great East Japan Earthquake judged from the stateof harbor/coastal areas and facilities
1017 Analysis of worldwide container ship conditions and container freight flow (2017)

Coastal, Marine and Disaster
Prevention Department
Port Planning Division
Port Planning Division

1018 Trend analysis and estimation of the actual conditions of OD freight flow for transshipment containers in major

Port Planning Division1019 Organization of fundamental data on mooring facilities, such as structural types
1020 Basic research concerning simplified calculation method of seismic intensity for inspection of vertical pile-type piers
1021 Inspection of consideration of improvement methods based on depth increase and improvement of gravity-type

Port Planning Division

ports of Japan and South Korea

quay walls (Part 1)

タイトル

Port Planning Division
Port Planning Division1022 Consideration of simplification of construction documents to raise productivity

Port Construction Systems andManagement Division

1023 Analysis of deterioration tendencies in port facilities

Port Construction Systems andManagement Division

1024 Consideration of application of 3D data and other methods to promote i-Construction in ports

Port Construction Systems andManagement Division

1025 Basic analysis of transition in the number of foreigners visiting Japan in recent years
1026 Design guide for reorganization of downtown road space
1027 Report on the subcommittee meeting of the National Institute for Land and Infrastructure Management Committee

Airport Planning Division

for Research Evaluation in the fiscal year of 2017
1028 Materials concerning the inspection of dam operation regulations and other items to introduce flood control
methods that utilize dams to their maximum functionality
1030 Collaborative research concerning the applicability of measurement and non-destructive inspection techniques toimprove inspection efficiency of highway bridges, etc. (III)1031 Research into methods for setting the state of design of highway bridges
1032 Collection of annual reports on investigative research related to sewage systems in FY2016
1033 The 2017 report on development of sewage system technologies
1034 Considerations of factors influencing liquefaction damage on flat sections of roads

Landscape and Ecology Division
Research Administration and
Evaluation Division
Water Cycle Division
Bridge and Structures Division
Bridge and Structures Division
Wastewater System Division
Wastewater System Division

1035 Main points regarding resilient structures in coastal dikes against tidal wave overflow
1036 Materials on technologies concerning planning methods for green spaces in disaster prevention systems - Handbook

regarding decisions on basic planning for green spaces to improve disaster prevention capabilities of cities and other topics -1037 The 2017 annual report on road survey costs and other topics

Pavement and Earthworks
Division
Coast Division
Landscape and Ecology DivisionRoad Traffic Department, Road
Structures Department
Social Capital Management Research● Receive information on research performed at NILIM
・ NILIM email service

Twice a month, we deliver the latest information introducing various research activities conducted by NILIM andlecture meetings, etc. Register here (URL and QR code) ☛ http://www.nilim.go.jp/lab/bcg/mailmag/index.html

・ 2018 Annual Report of NILIM

This website introduces NILIM research activities and achievements, as well as details of the latest research activities
to be formally initiated in the future. Go to this website: ☛ http://www.nilim.go.jp/lab/bcg/siryou/2018report/index.htm

Please take our reader survey: http://www.nilim.go.jp/lab/bcg/siryou/newsletter/nwslttr.htm
National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure, Transport and Tourism
Asahi 1, Tsukuba, Ibaraki, 305-0804, Japan(Tachihara) Tachihara 1, Tsukuba, Ibaraki, 305-0802, JapanNo.
(Yokosuka) Nagase 3-1-1, Yokosuka, Kanagawa, 239-0826, Japan
2 019
TEL: +81-29-864-2675
FAX: +81-29-864-4322
Editing/Publishing National Institute for Land and Infrastructure Management
http://www.nilim.go.jp/

66

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NILIM News Letter