HTT09-01

会場:101A

時間:5 月 25 日 09:00-09:15

台湾における地すべりの規模と降雨条件に関する研究
Rainfall conditions and magnitude of landslides in Taiwan
陳 麒文 1∗ ; 小口 高 1
CHEN, Chiwen1∗ ; OGUCHI, Takashi1
1
1

東京大学自然環境学専攻
Department of Natural Environment Studies, The University of Tokyo

This study analyzed 172 landslides in Taiwan during 2006-2012. These landslides were compiled from the reports of theSoil and Water Conservation Bureau of Taiwan. The area of each landslide was mapped and calculated using FORMOSA-II
images. The volume and depth were also calculated according to the empirical formula. Comparing the landslide size with
rainfall conditions interpolated from data for surrounding rain gauges, this study found that deep landslides usually occurred due
to long duration and moderate intensity rainfall, whereas shallow landslides occurred due to short duration and high intensity
rainfall. This observation is consistent with some previous studies and is ascribable to the fact that deep landslides need a highground water level caused by a prolonged rainfall. Concerning the area of landslides, their frequency-area distribution correlates
well with a power-law relation having an exponent of ?1.1, over the range 6.3×102 m2 <A L <3.1×106 m2 . The slope of thepower-law relation for Taiwan is lower than those for other areas around the world. It indicates that for the same total areaor total number of landslides, the proportion of large landslides will be higher in Taiwan than in other areas. This study also
proposed a landslide-event magnitude scale m L = log V a , where V a is the average volume of landslides associated with an
event. The average m L for all landslides during 2006-2012 was estimated to be = 6.4. In conclusion, the power-law relation of
frequency-area distribution is valid for recognizing characteristics of landslides in a specific area and the magnitude scale can beused to assess historical landslide events.
Keywords: landslides, rainfall, frequency-area, power-law, magnitude

1/1

HTT09-02

会場:101A

時間:5 月 25 日 09:15-09:30

Representation of landslide events and DEM sensitivity in relation to landslide susceptibility analysis
Representation of landslide events and DEM sensitivity in relation to landslide susceptibility analysis
PAUDEL, Uttam1∗ ; OGUCHI, Takashi2 ; HAYAKAWA, Yuichi S.2
PAUDEL, Uttam1∗ ; OGUCHI, Takashi2 ; HAYAKAWA, Yuichi S.2
1

Graduate School of Frontier Sciences, The University of Tokyo, 2 Center for Spatial Information Sciences, The University ofTokyo
1Graduate School of Frontier Sciences, The University of Tokyo, 2 Center for Spatial Information Sciences, The University ofTokyo
Landslides are naturally occurring complex geological phenomena that cause significant damages in mountainous regions
receiving heavy rainfall. Landslide susceptibility mapping is an important approach to mitigating such disasters. This study
highlights two important issues related to landslide susceptibility modelling. The first issue concerns the scale of a DEM.
We found that a single scale of topographic data does not correctly represent all the landslide conditioning factors making alandslide susceptibility model very sensitive to the scale in terms of DEM resolution. The second issue is related to the representation of landslide events for a susceptibility study. We found this important because all the raster cells in a landslide are
not equally responsible for its occurrence; neither can any single cell be representative. This consideration is often ignored in
the studies of landslide susceptibility. We analyzed five different approaches of landslide representation concerning seed-cells,
landslide-polygons and landslide-points and found that the seed cells around the landslide perimeter best represent the landslidecharacteristics. The inferences were made from landslide susceptibility studies at Niigata and Shikoku in Japan using a Random
Forest model, together with the landslide inventory collected by the National Research Institute for Earth Science and Disaster
Prevention (NIED) and the 10 m DEM from the Geospatial Information Authority of Japan (GSI).
キーワード: Landslide, susceptibility, DEM, Random Forest
Keywords: Landslide, susceptibility, DEM, Random Forest

1/1

HTT09-03

会場:101A

時間:5 月 25 日 09:30-09:45

Analysis of the landslides in Hiroshima caused by the typhoon-12 based on bivariate statistical landslide susceptibility
Analysis of the landslides in Hiroshima caused by the typhoon-12 based on bivariate statistical landslide susceptibility竇 傑 1∗ ; Paudel Uttam1 ; Oguchi Takashi2 ; Hayakawa Yuichi S.2
DOU, Jie1∗ ; PAUDEL, Uttam1 ; OGUCHI, Takashi2 ; HAYAKAWA, Yuichi S.2
1

Department of Natural Environmental Studies, The University of Tokyo, 2 Center for Spatial Information Science, The University of Tokyo1
Department of Natural Environmental Studies, The University of Tokyo, 2 Center for Spatial Information Science, The University of Tokyo
Following the heavy rainfall caused by the typhoon-12 on 20th August 2014, Hiroshima city in Japan was struck by a series oflandslides including numerous mudslides and debris flows. The landslides affected several suburban residential areas mostly in
the Asaminami and Asakita wards causing a great loss of property and the death of 74 residents. This study concerns a bivariate
statistical approach to analyse if a landslide susceptibility study would have been able to identify the vulnerable areas beforehand.
Firstly, we prepared a landslide susceptibility map (LSM) using a 10 m DEM, geological information and past occurrences oflandslides. The landslides after the typhoon event were later used to access the accuracy of the LSM. The inventory of landslides
before and after the typhoon event was interpreted from the high-resolution satellite images. The results show that a similarlandslide susceptibility study could have identified vulnerable areas and helped in mitigating the disaster.
Keywords: Hiroshima, landslide susceptibility mapping, typhoon, rainfall

1/1

HTT09-04

会場:101A

時間:5 月 25 日 09:45-10:00

Delineation of karst depressions using different digital elevation models
Delineation of karst depressions using different digital elevation models
CHEN, Hao1∗ ; OGUCHI, Takashi2 ; WU, Pan3
CHEN, Hao1∗ ; OGUCHI, Takashi2 ; WU, Pan3
1

Department of Natural Environment Studies, The University of Tokyo, 2 Center for Spatial Information Science, The Universityof Tokyo, 3 College of Resources and Environmental Engineering, Guizhou University, China
1
Department of Natural Environment Studies, The University of Tokyo, 2 Center for Spatial Information Science, The Universityof Tokyo, 3 College of Resources and Environmental Engineering, Guizhou University, China

The objective of this study is to investigate the effectiveness of DEMs derived from ASTER images, SRTM data and topographic maps to detect and quantify natural depressions in a karst area of Zhijin County, southwest China. Two methodologies
were implemented. The first method is a semi-automated approach for stepwise identification of the depressions using DEMs: 1)
DEM acquisition or arrangement; 2) filling sinks; 3) sink depth calculation using the difference between the original and sink-free
DEMs; and 4) removal of spurious depressions based on a threshold value of sink depth, morphometric parameters and TPI (Topographic Position Index). The second method is the traditional visual interpretation of depressions using high-resolution aerial
photographs and topographic maps. The threshold values of the depression area, shape, depth and TPI appropriate for identifying
true depressions were determined based on the comparison between the maps from the semi-automatic method and the visualinterpretation. The results show that the best performance of the semi-automatic method was achieved when the DEM derived
from the topographic maps was used along with the thresholds of area = 60 m2 , ellipticity = 0.2 and TPI = 0. The accuracy ofthe best method ranges from 0.78 to 0.95 when the DEM spatial resolution varies from 75 to 2.5 m.
キーワード: Karst depression, DEM analysis, Remote sensing, GIS
Keywords: Karst depression, DEM analysis, Remote sensing, GIS

1/1

HTT09-05

会場:101A

時間:5 月 25 日 10:00-10:15

Automated measurement of sand dune migration rates using multi-temporal LiDAR data
and GIS
Automated measurement of sand dune migration rates using multi-temporal LiDAR data
and GIS
DONG, Pinliang1∗
DONG, Pinliang1∗
11

Department of Geography, University of North Texas, USA
Department of Geography, University of North Texas, USA

Understanding how sand dunes form and migrate has long been a research topic in Earth and planetary surface processes.
An automated method was developed for measuring sand dune migration rates along the prevailing wind direction using multitemporal light detection and ranging (LiDAR) data and geographic information systems (GIS). Compared with traditional methods which involve labor-intensive and time-consuming measurements at individual locations, the new method allows for automated measurement of sand dune migration rates at hundreds or thousands of locations in a study area, and generation ofcontinuous raster datasets showing the spatial pattern of sand dune migration rates. Multi-temporal LiDAR data from White
Sands, New Mexico (USA) were used to demonstrate the application of the new method.
キーワード: Multi-temporal LiDAR, GIS, Digital elevation model, Sand dune migration, White Sands
Keywords: Multi-temporal LiDAR, GIS, Digital elevation model, Sand dune migration, White Sands

1/1

HTT09-06

会場:101A

時間:5 月 25 日 10:15-10:30

Evaluation of Erosion Rates on a Global Scale
Evaluation of Erosion Rates on a Global Scale
HECHT, Hagar1∗ ; OGUCHI, Takashi2
HECHT, Hagar1∗ ; OGUCHI, Takashi2
1

Department of Natural Environmental Studies, The University of Tokyo, 2 Center for Spatial Information Science, The University of Tokyo1
Department of Natural Environmental Studies, The University of Tokyo, 2 Center for Spatial Information Science, The University of Tokyo
Understanding the mechanisms and controlling factors of erosion rates is of great importance as it is a vital component ofboth geochemical and sediment mass balance studies, and a deep understanding of these processes will enable us to develop
accurate landscape evolution models. During the past decades scientists have been studying and measuring erosion rates using
different methods. Some examples use sediment yield, measure the rates of active surface processes, and estimate exhumation
rates through fission tracks, denudation rates using cosmogenic isotopes and even erosion rates through mass land wasting. A
major objective of these studies is to try and discover what the controlling factors of erosion rates are. Although most scientists
think that the two most important factors are climate and relief, no clear cut conclusion has been unanimously agreed upon in thescientific community.
Although erosion rates and sediment yield on a global scale have been studied before in relation to topographic conditions,due to lack of available data in the past, the analysis was relatively basic. Thanks to abundant newly obtained erosion rates data,
mainly using cosmogenic isotopes, combined with new DEM data, a more complete and comprehensive analysis can be made,and a correlation of erosion rates with factors such as basin morphometry or tectonic plate movement can be made. This paper
presents some results from the analysis.

キーワード: GIS, erosion rates, basin morphometry
Keywords: GIS, erosion rates, basin morphometry

1/1

HTT09-07

会場:101A

時間:5 月 25 日 10:30-10:45

フィリピンの災害対応を目的とする空間データ共有・可視化システムの開発
Developing a system of geospatial data sharing and visualization for disaster managementin the Philippines
小口 高 1∗ ; 小林 博樹 1 ; 早川 裕弌 1 ; 瀬戸 寿一 1 ; 近藤 康久 2 ; Mendoza Rene3
OGUCHI, Takashi1∗ ; KOBAYASHI, Hiroki1 ; HAYAKAWA, Yuichi S.1 ; SETO, Toshikazu1 ; KONDO, Yasuhisa2 ;MENDOZA, Rene3
1
1

東京大学・空間情報科学研究センター, 2 総合地球科学研究所, 3 フィリピン高度科学技術研究所
CSIS, Univ. Tokyo, 2 Res. Inst. for Humanity and Nature, 3 DOST-ASTI, Philippines

We have been conducting a collaborative research of Japanese and Philippine researchers to construct a system for disastermanagement in the Philippines. We focus on climatological data from numerous sensors with special attention to heavy rainfall.
We also construct a database including various geospatial data for natural and social environments, and develop a prototype
of data sharing and visualization system, which effectively connects the database and GIS (geographical information systems)
and can be used for disaster management. The Japanese researchers contribute mainly to the applications of GIS and open
source software based on their expertise. The Philippine researchers contribute to the applications of network and hardware
based on their knowledge on information technology. The system, after further development for practical usage, will be used for
preparation and mitigation of natural disasters in the Philippines.
Keywords: data sharing, data visualization, natural disasters, Philippines

1/1

HTT09-08

会場:101A

時間:5 月 25 日 11:00-11:15

Tsunami Vertical Evacuation Potential Analysis in the Shizuoka Metropolitan Area
Tsunami Vertical Evacuation Potential Analysis in the Shizuoka Metropolitan Area
VOULGARIS, Gerasimos1∗
VOULGARIS, Gerasimos1∗
1
1

University of Tsukuba, Spatial Information Science
University of Tsukuba, Spatial Information Science

The City of Shizuoka directly faces the Nankai Trough which has given two M8.1 earthquakes in modern history (1944 and1946), which were tsunamigenic. After the great Tohoku earthquake the Japanese government updated its worst case scenario
for a tsunami from the Nankai trough, which is expected to have a maximum run-up of 34m. This study aims to use GIS inorder to locate vertical evacuation sites in the City of Shizuoka within the existing urban structure, and to assess their potential in
supporting the citys population for immediate evacuation under variable tsunami inundation scenarios (34m, 20m, 10m and 5m
run up). A building population estimation model was applied to estimate the daytime and nighttime population of the buildings in
the city in order to determine the affected people and potential empty structures for evacuation. For the 34m inundation scenario
599,367 people are estimated to be in buildings touched by water in the nighttime and 326,554 people in the daytime. For the
weakest scenario of 5m run-up, 78,503 people are estimated to be in buildings affected by tsunami waters in the nighttime and54,264 people in the daytime. Inundation ratio analysis was conducted for all four scenarios. The inundation ratio shows thepercentage of a buildings height that is flooded in a certain scenario. Results show the largest amount of buildings to be flooded
by 75% or more in the case of the 34, scenario with numbers dropping significantly with the scenario severity.
キーワード: Shizuoka City, Vertical Evacuation, Nankai Trough, Tsunami, Population Estimation
Keywords: Shizuoka City, Vertical Evacuation, Nankai Trough, Tsunami, Population Estimation

1/1

HTT09-09

会場:101A

時間:5 月 25 日 11:15-11:30

Simulating Urban Heat Island Effects by Rapid Urbanization: A Case Study of Shanghai,
China
Simulating Urban Heat Island Effects by Rapid Urbanization: A Case Study of Shanghai,
China
GONG, Hao1∗ ; KUSAKA, Hiroyuki1 ; MURAYAMA, Yuji1
GONG, Hao1∗ ; KUSAKA, Hiroyuki1 ; MURAYAMA, Yuji1
1
1

Graduate School of Life and Environmental Sciences, University of Tsukuba
Graduate School of Life and Environmental Sciences, University of Tsukuba

As one of the most concerned urban climate events, to accurate represent the urban heat island phenomena from the pastscenario to the future scenario is my purpose. To achieve this task, a surface-atmospheric coupled model system was established,which included the image classification, urban growth model simulation, calculation of satellite retrieved LST data, calculationof anthropogenic heat flux density and atmospheric model simulation process.
On the other hand, in order to verify the surface-atmospheric coupled model system, as one of the most changing cities in
the world, Shanghai was selected to test the coupled model. As one of the mainly objective of this study was achieved with thedemonstration of the successful coupling two model system to simulate the urban heat island phenomena for Shanghai in threeselected study periods since the 1990s, when is the start year for Chinese economic reform in Shanghai.
For the results of the model simulation, the urban heat island phenomena in Shanghai can be excellently represented with thecoupled model. Furthermore, the coupled model can provide a spatial-temporal continuity solution to represent the urban heatisland during 30. Through these analyses, the availability of the methodology was proved. Finally, an attempt is made to utilize
the verified coupled model to evaluate and estimate the urban heat island effect of other mega cities or metropolitan areas.
キーワード: coupled model, land surface temperature, LULC, OBIA, urban growth model, urban heat island
Keywords: coupled model, land surface temperature, LULC, OBIA, urban growth model, urban heat island

1/1

HTT09-10

会場:101A

時間:5 月 25 日 11:30-11:45

Investigation Between Urban Traffic Accidents and Urban Structures from Spatial Perspective
Investigation Between Urban Traffic Accidents and Urban Structures from Spatial Perspective
HAJI MIRZA AGHASI, Niloofar1∗
HAJI MIRZA AGHASI, Niloofar1∗
1
1

Department of Geoenvironmental Sciences,University of Tsukub
Department of Geoenvironmental Sciences,University of Tsukub

Urban Traffic Accidents have been and continuing to be a major contributor of human and economic costs to requiring concerted multi-disciplinary efforts for sustainable effective prevention. Traffic accidents rank in the top ten causes of the global
burden of disease and injury, and will probably be in third place by 2020, when measured in disability-adjusted life years lost
(WHO, 2013). Urban structure and urban activities in a city or metropolitan area, make a significant involvement in generatinginteractions and accidents. Investigation of traffic accidents and urban structures such as road networks, land use patterns, public
facilities, etc. from spatial perspective is important for future urban planning processes The urban interactions and activities canhappen between districts or within a district, on different roads and different time and space.
The study area of this study is Tehran city which include 22 districts. Tehran is the largest city in Iran and also its capital. Its
population is close to 12 million during day time and over 8.5 million people at night. The analysis in this study is based on dataobtained from the Police Department of the Islamic Republic of Iran, Tehran. The main database contains information about allpolice-reported urban traffic accidents that occurred in 2011 in Tehran. Tehran has experienced a rapid growth of urban population. With the expansion of the city boundaries, even though there is an occurrence of urban transportation and large usage of cars
for daily urban trips and large number of accidents, make the Tehran accident problem more serious. The Tehran spatial structure
has a high density structure combined with a several central pattern. The lack of strong and unique essence, as easily as the spatial distribution of employment, are mostly associated with the build-up density and accidents but less dangerous accidents. The
current spatial structure of Tehran, which is a high density city unaccompanied by influential Central Business District (CBD)
creates several limitations, so that we can see the distribution of the accidents whole of the city. A rapid and continued rise inliving accommodations and land costs is expected in cities with transportation improvements and rapid economic and population
growth. Humans, nations, regions and the world would be seriously limited in development without transportation, which is acentral element for physical and economic growth. Urban growth occurred as physical and functional changes took place, due
to the transition of the rural landscape to urban forms, which has been studied by various researchers (Thapa and Murayama,2010). These changes as well influence the urban density, which would be the increase of the growth rate in several dimensions.
Transportation network systems, urban construction and urban traffic accidents are interdependent each other. Urbanization istaking place at a rapid pace in Tehran, and this expanding city is changing the urban structure. Land use is one of the mostimportant pillars in creating urban areas, and thus, creating transportation and road patterns have a direct impact on urban traffic
accidents. The combination of high population and growth of land use causes the increase of daily trips that produce urban
traffic accidents in the city. Agreeing to this varying communication between land use and the road network, which is causing
traffic accidents, also calls for an agreement on how the land use is associated with urban traffic accidents. An explanation of
the connection between the several land uses and occurrence of urban traffic accidents in Tehran’s metropolitan area indicatesthat land use generates different kinds of causes, which are brought about by various actions. It is necessary therefore to havean understanding structure of urban and accidents for improving safety on the roads which will be done with GIS as GIS is acomprehensive management tool for traffic safety.
キーワード: Urban structure, Urban Traffic Accidents, Spatial Analysis, GIS
Keywords: Urban structure, Urban Traffic Accidents, Spatial Analysis, GIS

1/1

HTT09-11

会場:101A

時間:5 月 25 日 11:45-12:00

Geospatial analysis of urban landscape patterns in four hill stations of Southeast Asia
Geospatial analysis of urban landscape patterns in four hill stations of Southeast Asia
ESTOQUE, Ronald C.1∗ ; MURAYAMA, Yuji1
ESTOQUE, Ronald C.1∗ ; MURAYAMA, Yuji1
1
1

Faculty of Life and Environmental Sciences, University of Tsukuba, Japan
Faculty of Life and Environmental Sciences, University of Tsukuba, Japan

Hill stations are commonly used to refer to a town or city in the tropics founded by a Western colonial power during thenineteenth and early twentieth centuries. Most hill stations are located in mountain regions at an altitude between 1000 and2500 m above sea level, and thus enjoy relatively moderate temperatures than those recorded in the surrounding lowlands. Hill
stations are known for their relatively good natural environments, which generate valuable ecosystem services that benefit the
local population. In recent years, there has been a resurgence of interest in hill stations for ’quality environment’ and othersocioeconomic development-related activities, resulting in the rapid urbanization of some. However, rapid urbanization affects
the fragile natural environment and threatens the sustainability of these areas. That said, not much is known about the landscapepatterns of these areas. Hence, this study aims to contribute to our understanding of some of these areas by examining the urban
landscape patterns of four notable hill stations in Southeast Asia, namely Baguio City (Philippines), Bogor (Indonesia), Dalat(Vietnam) and Pyin Oo Lwin (Myanmar). Geospatial tools and techniques, including remote sensing and GIS, will be used tofacilitate the analysis.
キーワード: hill station, geospatial analysis, land use, land cover, GIS, remote sensing
Keywords: hill station, geospatial analysis, land use, land cover, GIS, remote sensing

1/1

HTT09-12

会場:101A

時間:5 月 25 日 12:00-12:15

Spatial Analysis of Land Use/Cover Changes and Urban Expansion in Lusaka City, Zambia
Spatial Analysis of Land Use/Cover Changes and Urban Expansion in Lusaka City, Zambia
SIMWANDA, Matamyo1∗
SIMWANDA, Matamyo1∗
1
1

Graduate School of Life and Environmental Sciences; University of Tsukuba
Graduate School of Life and Environmental Sciences; University of Tsukuba

Major cities in Sub-Saharan Africa have experienced an unprecedented rate of urban expansion, including Lusaka, the capital
city of Zambia. Urban expansion has increased the exploitation of natural resources and has changed Land Use and Land Cover(LULC) patterns. In this study, Geographical Information Systems (GISs) and Remote Sensing (RS) were used to spatially analyze the LULC changes in Lusaka City as a determinant of urban expansion. Muti-temporal Landsat Thematic Mapper (TM)and Enhance Thematic Mapper Plus (ETM+) images from 1990, 2000 and 2010 were classified into three categories (Built,
Non-Built and Water) and the magnitude of LULC changes are presented. The results show that there has been rapid increase in
the built up area of Lusaka City especially between the periods 2000 and 2010. It was observed that the expansion in the built up
area is highly characterized by increase in unplanned (slum) settlements. The study has also utilized Census data from the year
2000 to 2010 to determine the driving forces of Urban Growth and express the social economic profile of the city.
キーワード: Spatial Analysis, Land Use/Cover, Urban Expansion, Lusaka City
Keywords: Spatial Analysis, Land Use/Cover, Urban Expansion, Lusaka City

1/1

HTT09-13

会場:101A

時間:5 月 25 日 12:15-12:30

A WebGIS Platform for Repository, Processing and Disseminating Urban Land-Use/Cover
Maps
A WebGIS Platform for Repository, Processing and Disseminating Urban Land-Use/Cover
Maps
MURAYAMA, Yuji1 ; ESTOQUE, Ronald C.1 ; SIRIWARDANA, Halgamage malinda1∗
MURAYAMA, Yuji1 ; ESTOQUE, Ronald C.1 ; SIRIWARDANA, Halgamage malinda1∗
1
1

Graduate School of Life and Environmental Sciences,University of Tuskuba
Graduate School of Life and Environmental Sciences,University of Tuskuba

This paper discusses a WebGIS designed to open up an ample opportunity for researchers and information holders to store,
maintain and disseminate remote sensing-derived urban land-use/cover maps. The WebGIS platform consists of the acquisitionengine, repository engine, processing engine and service engine, visualizing engine, and the disseminator engine. Firstly, theacquisition engine uses the input server to acquire classified images and other relevant source imageries and then passes it to therepository engine. The repository engine manages the data storage by extracting metadata related to imageries and by keywords,
together with other metadata related to users. The repository engine also checks if there are any classified images currently stored
in the system related to the same geographic location and time period. If the image is a derived work from an existing image
then an image stack is created and stored with the new set of metadata. The processing, aggregation and comparison of images
are done and stored in the system therefore another person can examine, use and improve with further modifications. The open
source modules are created to provide visualization of urbanization process as a by-product by acquiring and processing datafrom the repository. Based on the classified data in the repository, the system gives a service to any website or user to display andvisualize the urbanization process of any particular geographic location. The goal of the research is to establish a self-evolving
WebGIS platform for repository, processing and distribution of remote sensing-derived urban land-use/cover maps for the purpose of visualizing urbanization process and other relevant geospatial analyses.
キーワード: Geo-data Repository, Geospatial Analysis, Land-Use/Cover, Remote Sensing, Urbanization, WebGIS
Keywords: Geo-data Repository, Geospatial Analysis, Land-Use/Cover, Remote Sensing, Urbanization, WebGIS

1/1

HTT09-14

会場:101A

時間:5 月 25 日 12:30-12:45

Functional and Morphological Dynamics: Colombo city, Sri Lanka
Functional and Morphological Dynamics: Colombo city, Sri Lanka
SUBASINGHE, Shyamantha1∗
SUBASINGHE, Shyamantha1∗
11Graduate School of Life and Environmental Sciences, University of Tsukuba
Graduate School of Life and Environmental Sciences, University of Tsukuba

The urban functions and urban morphology of Colombo city has been dramatically changing over last decades. Main objectiveof this study is to fundamentally analyze the spatiotemporal changes of urban morphology of Colombo city and explains therelationship between urban morphology changes and functional changes in Colombo city. Three methods are used to achieve
its objective. First, the Landsat imageries 1992, 2005 and 2014 are classified to represent the urban and non-urban areas using
Random Forest (RF) approach in Remote Sensing (RS). Second, the accuracy of the classification results is assessed. Third, thehorizontal changes of urban morphology is analyzed in quantitatively using Geographical Information System (GIS). Moreover,the study analyzes how the socioeconomic functions of Colombo city has changed in different time period and its relationshipwith urban morphology changes, in order to understand the causes of spatial pattern of changes of Colombo city. The outcomeof the study can be used to model the urban morphology changes in horizontal manner but vertical expansion should be detected
in order to model it in a comprehensive manner in future.
キーワード: GIS, Random Forest, RS, Urban morphology
Keywords: GIS, Random Forest, RS, Urban morphology

1/1HTT09-15

会場:101A

時間:5 月 25 日 14:15-14:30

ヘドニック回帰モデルに基づく新築住宅の価格に関する研究―中国西安市を事例に
Hedonic Price Modeling of New Residential Property Values in Xi’an City,China
LIU Kai1∗
LIU, Kai1∗
1
1

筑波大学大学院生命環境科学研究科地球環境科学専攻
Master’s Program in Geoscience in the Graduate School of Geoenvironmental Science,Tsukuba University

With the urban growth in Chinese cities, residential property values have become one of the most important determinants
measuring urban economic development. However, it is complicated to carry out quantitative analyses focusing on residential
property values in a whole city. This thesis estimates the implicit premium of several location influence factors affecting newresidential property values in Xi’an, using hedonic pricing technique. Three types of given explanatory variables are createdor collected to measure the location characteristic, characteristics specific to the housing itself and neighborhood characteristics
from a 378-samples database. Hedonic pricing model is employed to estimate the capitalization effects of these influence factors
in new residential property values. The empirical results show that the accessibility indices such as distance to CBD have wellbeen capitalized into the residential property values. In particular, results indicate that a within-zone housing unit is sold 9.4%
more than if it was outside the attendance zone of a Key Primary School. Besides, this study educed a specific threshold value(825 meters) about the residence inside a Key Primary School’s attendance zone from several repeating regression processes inorder to achieve the target with statistical significance at 5% level. An attempt is made to quantize the premium on the residential
property from the influence of educational resources, i.e. home buyers have willingness-to-pay for the high-quality educational
resource. In addition, we get a corollary that it is distinctive comparing with other metropolises that the accessibility to subway
stations has not well and significantly been capitalized into residential property values in the real estate market of Xi’an City until
April 2014. In other words, advantages of rail transportation had not yet adequately been brought into full play in Xi’an City.
Then, it is verified that spatial local singularities caused by unobserved variables or estimation bias can be associated with
Multi-regression errors. This thesis has explored an unconventional viewpoint to residual error problem, which combines thespatial particularity related to location differences (Coming from the aspect of real world) and the spatial distributions of singularities (Feedback from the aspect of data).
Furthermore, this thesis classifies the new residences in Xi’an City into 5 agglomerations and aims to prove some hypotheses that following with results of the residual analysis, which can reveal the trend of housing price and the real estate market
prospects of new residential properties within each region of Xi’an City.
The author takes Xi’an City, which is thought as a comparatively un-modernized city, as the study area, which can provide
one new research example of hedonic pricing model comparing with the other metropolises in China. Besides it is effective toprovide scientific basis of decision-making for the real estate investors and planners.
キーワード: クラスター分析, ヘドニック回帰モデリング, 新築住宅の価格, 残差, 「学区房」
Keywords: Cluster analysis, Hedonic price modeling, New residential property values, Residuals, School’s attendace zone

1/1

HTT09-16

会場:101A

時間:5 月 25 日 14:30-14:45

Evaluating Walkability through Neighborhood Design Qualities using GIS: A Case Studyof Suburban Areas in Tokyo
Evaluating Walkability through Neighborhood Design Qualities using GIS: A Case Studyof Suburban Areas in Tokyo
HOU, Hao1∗
HOU, Hao1∗
1
1

Graduate School of Life and Environmental Sciences, University of Tsukuba
Graduate School of Life and Environmental Sciences, University of Tsukuba

Suburbanization leads to a new neighborhood structure compared with traditional ones which have plenty of spaces anddestinations for residents to walk. This new structure consists of residential dwellings mostly with only few places for daily
activities such as shopping or working. Such a neighborhood is considered as a low ? walkability neighborhood which causes
physical inactivity. Walkability is a measure of effectiveness of neighborhood design in promoting walking and improvement of
walkability has been found as a solution to achieve healthy life style. The purpose of this study is to figure out important factors
for evaluating walkability in such areas and find a proper model with these factors to calculate walkability of suburban areas inTokyo.
Six main factors (dwelling density, road accessibility, land use diversity, public transportation facilities, aesthetics and safety)
are selected and GIS methods, combined with questionnaires, are used for collecting and analyzing data. Dwelling density, roadaccessibility and public transportation facilities are evaluated by census data while land use diversity, aesthetics and safety areevaluated by data from both questionnaires and census. Zonal analysis is used to include the effects from the surround cellvalues. Then in order to detect the importance of each factor, expert opinion in Analytic Hierarchy Process (AHP) analysis isused by giving weights to each factor. Subsequently, all the six factors are shown with their own weights through map layers
and these map layers are overlaid to get the final walkability map in the study area. Based on the final walkability map and fielddata obtained, powerful factors and weak factors are summarized with the characteristics of each study area. Possible ways inpromoting walkability is concluded according to the walkability map and questionnaire results.

キーワード: GIS, walkability, neighborhood design, suburban areas, physical activity
Keywords: GIS, walkability, neighborhood design, suburban areas, physical activity

1/1

HTT09-P01

会場:コンベンションホール

時間:5 月 25 日 18:15-19:30

降雨強度データを用いた機械学習による簡易水害リスク評価手法の構築
Simple Evaluation Method for Flood Risk Using Rainfall Intensity Data and Machine
Learning
佐藤 李菜 1∗ ; 小口 高 2
SATO, Rina1∗ ; OGUCHI, Takashi21
1

東京大学大学院新領域創成科学研究科, 2 東京大学空間情報科学研究センター
Graduate School of Frontier Science, The University of Tokyo, 2 CSIS, The University of Tokyo

Floods especially pluvial flooding, is a major disaster in Japanese urban areas. Simulations are often used to assess flood risk,
but such approaches tend to be highly complicated. Therefore, some simple methods using topographical indices, land use andrainfall data with statistical approach have been proposed. However, the accuracy of such methods is still low. This study aims
to analyze the characteristics of flooded areas in the 23 wards of Tokyo and construct a simple method for evaluating flood risk
using rainfall intensity data and machine learning. Radar rainfall data from the Japan Meteorological Agency were analyzed
using Random Forest, a method of machine learning. The accuracy of the models constructed by Random Forest for flooded
areas is almost 100% in many districts, but the accuracy for non-flooded areas are low. It means that the models can well predictflood occurrence, but many non-flooded areas are estimated as flooded areas. Therefore, it is necessary to improve the model.

キーワード: 水害, 降雨強度, 機械学習, GIS
Keywords: flood, rainfall inrensity, machine learning, GIS

1/1

HTT09-P02

会場:コンベンションホール

時間:5 月 25 日 18:15-19:30

航空機 LiDAR 点群データによる山地河川の粗度の計測
Survey on grain roughness in a mountain river by using airborne LiDAR point cloud data
蒋 香旭 1 ; 清水 武志 1∗ ; 藤村 直樹 1 ; 石塚 忠範 1
JIANG, Xiangxu1 ; SHIMIZU, Takeshi1∗ ; FUJIMURA, Naoki1 ; ISHIZUKA, Tadanori1
1
1

国立研究開発法人 土木研究所
Public Works Research Institute

Small-scale topographic features are commonly found on a mountain river. One of the important features is grain roughness for
affecting the water flow or debris flow resistance of the mountain channel. One of the difficulties is to measure grain roughness
in a mountain river because a lot of grains and rocks are larger than a few meter diameter.
In this study, we use a point-cloud data earned by airborne LiDAR to calculate simple statistical indexes of the roughness
in the lattice bins covered with the objective region of the mountain river. The results comparative with the in-situ grain size
distribution earned by the grid count method show relatively good relationship.

キーワード: 山地河川, 粗度, 航空機 LiDAR
Keywords: mountain river, grain roughness, airborne LiDAR

1/1

HTT09-P03

会場:コンベンションホール

時間:5 月 25 日 18:15-19:30

The annual net ecosystem exchange in a subtropical broadleaf plantation in southern Taiwan.
The annual net ecosystem exchange in a subtropical broadleaf plantation in southern Taiwan.
LAI, Yenjen1∗ ; YU, Jui-chu1 ; CHANG, Cheng-sheng1 ; CHEN, Jiquan2 ; TSAI, Ming-jer3 ; WANG, Ya-nan3
LAI, Yenjen1∗ ; YU, Jui-chu1 ; CHANG, Cheng-sheng1 ; CHEN, Jiquan2 ; TSAI, Ming-jer3 ; WANG, Ya-nan3
1

The Experimental Forest, National Taiwan University, Taiwan, 2 IceMe, Nanjing University of Information Science & Technology, China; and University of Toledo, USA, 3 School of Forestry and Resource Conservation, National Taiwan University, Taiwan
1
The Experimental Forest, National Taiwan University, Taiwan, 2 IceMe, Nanjing University of Information Science & Technology, China; and University of Toledo, USA, 3 School of Forestry and Resource Conservation, National Taiwan University, Taiwan
Carbon flux of regenerating vegetation is considered as a major factor in determining the sequestration strength and associateduncertainty of terrestrial ecosystems and its role in slowing down the increase of atmospheric CO2 concentration. In the purposeto quantify the long-term net exchanges of carbon, water, and energy between the broadleaf plantation and the atmosphere, thisstudy picked an existed reforested sugar cane farm which was reforested by multiple broadleaf species from 2002 to 2005 in
Pingdong, southern Taiwan as a field site and installed an open-path eddy-covariance tower since 2008. The tower-based annual
net ecosystem exchange (NEE) were -1.0, 1.3, 0.5, and -1.0 Mg C ha−1 yr−1 for 2009-2012, respectively. However, these results were conflicted with biometric investigation. A further study using Hsieh’s footprint model (Hsieh et al., 2000) combinedwith geographic information system (GIS) showed most of the flux sources were within the range of 250 m and monsoon andperiodic winds existed clearly. The tower-based NEE could be mis-explained because the daytime and nighttime flux sources
actually came from different plantations/species. The tower-based Re (ecosystem respiration) was over-estimated about 0.56
umol m−2 s−1 . The annual mean NEE in plot no.10 and no.11 was -3.12, -0.87, -1.58, -3.09 Mg C ha−1 yr−1 for 2009 to 2012,
respectively after a simple revision.
キーワード: carbon dioxide flux, eddy covariance, net ecosystem exchange (NEE), plantations of multiple broadleaf species,
footprint
Keywords: carbon dioxide flux, eddy covariance, net ecosystem exchange (NEE), plantations of multiple broadleaf species,
footprint

1/1