Road roughness condition information is very important for the maintenance planning and management of road infrastructure. Collecting such information is time and resource consuming because it usually requires either, if not all, skillful manpower, substantial budget, and sophisticated equipment. Therefore, collecting and updating road roughness condition is viewed as a big challenge for many road authorities. The final goal of our research is to explore for a low cost and easy to use approach for the aforementioned purpose by using Android smartphones to estimate road roughness and traffic conditions. In this study we develop a model based on a relationship function of smartphone sensor data and road roughness condition. The relationship function is drawn from our experiment in Vientiane, Laos, in which we have found that the acceleration data from smartphones has a linear relationship with road roughness condition and the significant of the relationship also partly depends on speed. The most important and unique feature of the model is the ability to estimate road roughness condition using data obtained from anonymous drivers. Preliminary numerical examples and simulations using real sensor data have been carried out whereas the findings show that performance of the model and results are very promising.
政策形成や計画策定の過程では多様な価値観や利害を有する関係者間の調整が行われるが，近年，都市・環境政策分野の研究と実務で，ファシリテーターなどの調整役が注目されている．この調整の実態を探索的に理解する方法論として，「実践のプロファイリング（Profiles of Practitioners）」手法を本研究ではレビューした．現場で起きたことがらをストーリーとして聞き取り，その書き起こしの分析を通じ，合意形成の技法に関する規範的な議論や評価では表出しない実態を捉える手法である．本研究は，合意形成を研究する上で重要な手法として，同手法の特徴と位置づけを明らかにすることを目的としている．
企業間の業務交通が産業集積の一因であることは古くから指摘されている．そこで本研究では，パーソントリップ（PT）調査の業務交通トリップデータを用いて産業集積の度合いを計測することを試みる．具体的には，小ゾーン単位の東京都市圏PT調査の産業分類別打合せ・会議トリップに空間スキャン統計量（spatial scan statistics）を適用することで，東京23区における産業分類別の打合せ行動の空間的な集積やその変化を考察する．また，当該集積パターンと産業分類別従業員数の空間集積パターンを比較し，後者が前者を必ずしも拿捕し得るものではないことを指摘する．本研究の結果は，08年東京PT調査では対象外とされた業務交通トリップに関する調査が，face to faceのコミュニケーションの定量化のための有用な基礎資料と成り得ることを実証的に示すものである．
Sustainable transport systems are increasingly required for Asian developing cities where economic growth causes further burden to the environment from urban transport. However, environmental performance is hardly prioritized for their transport policies, and it is therefore necessary to make such transport systems more attractive. This study is aimed at quantitatively evaluating the attractiveness of transport mode in Asian developing cities. With data of a questionnaire survey in Bangkok, it measures the levels of preferences for various attractiveness factors in travel, classifying them into convenience, comfort and safety elements. Using the parameters of preferences, the attractiveness of travel is evaluated for car, conventional bus, and mass rapid transit both for a current situation and potential improvement. The results show that, while the attractiveness varies by income and age, public transport can be as attractive as car by improving the quality of mass rapid transit.
Given the limitations of new urban railway construction in the Tokyo metropolitan area, a time-varying fare policy is expected to be one of the most effective measures to spread the concentrated peak demand. This paper presents an empirical study that examined the theoretical time-varying marginal utility model introduced by Vickrey (1973), using data on urban rail commuters in Tokyo. Then, the departure-time-choice model, under deterministic user equilibrium, was proposed by integration with the empirically identified time-varying marginal utility model. The outputs of the equilibrium model were compared with the results from the traditional constant marginal utility model; our results indicated that the former outputs would be more suitable for a commuting pattern with longer travel distance, similar to the Tokyo case. The equilibrium scheduling pattern and the first-best pricing strategy were examined; our study showed that the time-varying marginal utility model was capable of capturing the marginal external cost more precisely for travelers with a relatively flexible arrival time.