ダッカ住民の地震に関するリスク認知と意識

京都大学0048新制・課程博士博士(地球環境学)甲第22105号地環博第191号新制||地環||37(附属図書館)京都大学大学院地球環境学舎地球環境学専攻(主査)教授 宇佐美 誠, 准教授 SINGER JANE, 准教授 吉野 章学位規則第4条第1項該当Doctor of Global Environmental StudiesKyoto UniversityDFA

Sparse structural equation models for causal inference in genetic studies of multiple phenotypes with next-generation sequencing data

Despite their differences in selection of specific methods for estimation, the widely used methods for genetic analysis of complex traits do not detect, distinguish and characterize the true biological, mediated and spurious pleiotropic effects and are unable unravel causal structures among multiple phenotype and genotype variants. Overcome these limitations, we develop sparse structural equation models (SEMs) as a general framework for a new paradigm of genetic analysis of multiple phenotypes. To incorporate both common and rare variants into the analysis, we further extend the sparse multivariate SEMs to sparse functional SEMs. To improve computational efficiency and reduce dimension of the data, functional data analysis techniques and thealternative direction methods of multiplier (ADMM) are used to develop a novel sparse two-stage least square estimation method for the structure and parameter estimation of the SEMs with the large size. Borrowing causal information from the SEMs and maximizing the power of marginal association analysis, we develop a novel statistic for testing association of genetic variants with multiple variants. By large scale simulations we show that the true network structure can be accurately recovered by our models and the new statistics has higher power than the PCA-based statistics.The proposed method is applied to exome sequence data from the NHLBI’s Exome Sequencing Project (ESP) with 11 phenotypes, which identify a network with140 genes connected to 11 phenotypes and 15 genes with pleiotropic genetic effects and demonstrate that the proposed statistic has smaller P-values than the PCA-based statistics for testing marginal associations

Modelling flyover induced travel demand in Dhaka, Bangladesh

This research evaluates induced travel demand with the construction of transport infrastructure in Dhaka, Bangladesh using flyovers as a case study. It examines whether transport infrastructure induces travel behaviour changes of individuals and explains that flyover users did not generate any induced travel kilometres. However, flyover users switched their travel mode, route, and residential location for travel time savings. The findings contribute to guide policies that include the effects of induced travel demand when constructing new roadway facilities, such as flyovers in Dhaka and other similar cities in developing countries

洋上風力・潮力ハイブリッド発電システム

京都大学0048新制・課程博士博士(エネルギー科学)甲第15686号エネ博第227号新制||エネ||50(附属図書館)28223京都大学大学院エネルギー科学研究科エネルギー応用科学専攻(主査)教授 白井 康之, 教授 平藤 哲司, 教授 手塚 哲央学位規則第4条第1項該当Doctor of Energy ScienceKyoto UniversityDA

The impacts of transport infrastructure development on travel route switch behavior in Bangladesh

A better understanding of individuals’ route switch behavior is required totake the best possible interventions to alleviate roadway traffic congestion. Theimpact of different transport infrastructure, including new roads, highways, andmotorways, on reducing traffic congestion and travel time savings was reported inthe literature. However, the effect of flyovers on travel route switch behaviorremains unexplored, particularly in developing countries. Therefore, this studyinvestigates individuals’ route switch behavior due to the construction of flyovers in Bangladesh. An intercept survey was conducted to collect data from flyover users in Dhaka. A chi-square test was used for categorical variables and one-way ANOVA was performed for continuous variables to compare participants’ socio-economic and travel characteristics with their route switch behavior. A multiple response set was used to determine why participants were not using the same or alternative travel route for regular trip purposes. Using a binary logit model, the study found a significant association between flyover users’ socio-economic and travel characteristics, and their travel route switch behavior. Flyover users who changed their route traveled more kilometers and generated more trips compared to flyover users who did not change their routes. Flyover users were also switched travel routes to save their travel time. Transport planners and practitioners should consider individuals’ route switch behavior when planning for new transport infrastructure to reduce traffic congestion, particularly in large cities such as Dhaka, Bangladesh. Future studies should also explore individuals’ route switch behavior in other urban settings

Modelling induced mode switch behaviour in Bangladesh: A multinomial logistic regression approach

This paper assesses induced mode switch behaviour with the construction of transport infrastructure using flyovers as a case study. Understanding travel mode switch behaviour is essential to identify the reasons for choosing one mode of transport over another. Travel mode switch behaviour needs to be considered for efficient transport infrastructure planning. However, very little is known about mode switch behaviour of individuals due to the construction of transport infrastructure such as flyovers on roadways particularly in the context of developing countries. This research examines whether the construction of flyover infrastructure induces travel mode switch behaviour of individuals. The study also considers a non-flyover road in order to have a comparison between results from flyover and non-flyover users. The objective of this research are: to measure induced mode switch behaviour caused by the construction of transport infrastructure; and to model induced mode switch behaviour. Using purposive sampling technique, the data was collected through an intercept survey and online questionnaire from 1060 vehicle users who used flyover and non-flyover roads based on the percentage of modal share in Dhaka. A Multinomial logistic regression model determined that flyovers have a significant impact on induced travel mode switch behaviour of individuals. Induced mode switch made by non-flyover road users are also reported. The study found that flyover users were three times more likely to shift their travel mode to private transport in order to save travel time compared to the flyover users who did not change their travel mode. This research suggests that the benefits of travel time savings for each travel mode should be taken into account when providing or evaluating new transport infrastructure. Otherwise, traffic congestion will return due to an increase of private transport, and will minimize the benefits of travel time savings

Modelling induced travel demand in a developing country: evidence from Dhaka, Bangladesh

This research evaluates induced travel demand with the construction of transport infrastructure, using flyovers as a case study. Induced travel demand is defined as an increase in travel as a result of any increase in the capacity of a transportation system. However, relatively little is known about the induced travel demand effects of flyover infrastructure in developing countries.This research endeavours to answer the question of whether the construction of flyover induces travel kilometers or induced trips. The objectives of this research are to estimate average travel distance and trip frequencies based on socio-economic and travel characteristics of flyover and non-flyover users; to measure induced travel kilometres and induced trips caused by construction of flyovers; and to model induced travel kilometres and induced trips. Using purposive sampling techniques, both an intercept survey and online questionnaire were conducted to collect the data from 1060 vehicle users who used flyover and non-flyover roads in Dhaka.An independent samples t-test estimated that there is a statistically significant difference between flyover and non-flyover users. Induced travel kilometres and induced trips made by these two groups are also reported. Using a linear multiple regression model, the study found that the number of trip frequency of flyover users is increased by 0.350 owing to a one-minute savings in their travel time. The findings of this research contribute to guide policies that include the effects of induced travel demand when constructing new roadway facilities, particularly in Dhaka and other cities in developing countries

Output power control of hybrid off-shore-wind and tidal turbine generation system with battery storage system

Generally, the wind-power output fluctuation is compensated by a rather large capacity battery system. In order to reduce the capacity of the battery, long term fluctuation component should be reduced. We have proposed a hybrid generation system which is composed of large scale off-shore wind farm with small scale tidal generation system (HOTT; Hybrid Off-shore and Tidal Turbine). The basic concept of HOTT generation system is to compensate wind power fluctuation by controlling the output of tidal generation system. If the tidal power compensates some long-term portion of the wind fluctuation, the battery capacity can be reduced. In this study, for coordinating compensation by the tidal generator and the battery, a control system was designed limiting compensating frequency range by using band pass filter and phase compensation. The characteristics of this system was investigated by simulation studies

Active Transport to School and School Neighbourhood Built Environment across Urbanisation Settings in Otago, New Zealand

The school neighbourhood built environment (BE) can facilitate active transport to school (ATS) in adolescents. Most previous studies examining ATS were conducted in large urban centres and focused on BE of home neighbourhoods. This study examined correlations between school-level ATS rates among adolescents, objectively measured school neighbourhood BE features, and adolescents’ perceptions of the school route across different urbanisation settings. Adolescents (n = 1260; 15.2 ± 1.4 years; 43.6% male) were recruited from 23 high schools located in large, medium, and small urban areas, and rural settings in Otago, New Zealand. Adolescents completed an online survey. School neighbourhood BE features were analysed using Geographic Information Systems. School neighbourhood intersection density, residential density and walkability index were higher in large urban areas compared to other urbanisation settings. School-level ATS rates (mean 38.1%; range: 27.8%–43.9%) were negatively correlated with school neighbourhood intersection density (r = −0.58), residential density (r = −0.60), and walkability index (r = −0.64; all p < 0.01). School-level ATS rates were also negatively associated with adolescents’ perceived safety concerns for walking (r = −0.76) and cycling (r = −0.78) to school, high traffic volume (r = −0.82), and presence of dangerous intersections (r = −0.75; all p < 0.01). Future initiatives to encourage ATS should focus on school neighbourhood BE features and minimise adolescents’ traffic safety related concerns