This study sets two research interests based on existing studies which have estimated high values of time (VOT) of cargoes. The first interest is the cause of such high VOT of cargoes. The second interest is that high VOT of cargoes can increase the buffer capacity of freight transport. Under these research interests, this study theoretically analyzes the relation between lead time and profit of consignee, and the relation between VOT of cargoes and buffer capacity of truck transport. The analysis finds the following theoretical implications. Other things being equal, VOT of cargoes can be higher when the travel distance is shorter or the consignee is small. Shortening travel time of trucks can reduce the buffer capacity of trucks, and thus can save the cost of trucking industry.
This paper analyzes changes in regional car kilometers traveled (CKT) per private passenger car under a reduction in CO2 emissions in Japan by using the Modified Laspeyres Index (MLI) Decomposition. The decomposition shows that the dominant factor in a decrease in CKT per car over the period 2003-2008 is a fuel price increase in both urban and rural regions under a reduction in household income; however, changes in CKT per mini car are small over the period. Whereas, the dominant factor in an increase in CKT per car over the period 2010-2013 is an increase in fuel expenses per household under the decrease in household income. Needs of the mini cars are increasing in place of the standard and small cars, particularly in the rural regions where transport mostly relies on private passenger cars.
This research focuses on the uses and management of the streets operated by the ‘Plaza Program’ in New York City. Plaza Program is one of the local governmental policies of New York City which has created more than 60 pedestrianized spaces for its neighborhoods and citizens since 2008. The Study aims to clarify how the past policies on streets influences the contents of the Program and to analyze the effects and issues of the current management system organized by both of public and private sectors from the view of community vitalization. As results, it points out the key factors for realizing the implementation of large numbers of plazas in a short term and advantages of Plaza Program compared with other means of pedestrianization such as construction of malls. This research was conducted with field surveys, document reviews, and interviews with the New York City Department of Transportation, non-profit organizations concerned with the Program and local private sector such as Business Improvement Districts. Consequently, the paper points out the key factors for implementation of plazas and their management: 1) the non-profit organizations with experts on place making and job training fosters the uses and maintenance of the streets by various types of local private organizations, by giving the technical supports and human resources, 2) cross-departmental teamwork inside the city government office and 3) comprehensive special planning of the plazas with efficient uses of existing facilities along the streets. Additionally, the research suggests the advantages of the Plaza Program system in the points of 1) small sized pedestrianization lightens the burden of private sectors with no experience of management, 2) flexible furniture and plans for visitors and event uses, 3) giving priority to the communities which are ready for pedestrianization and 4) clear role-sharing between public and private sectors.
This study aims to develop a traffic demand prediction model for national expressways based on user equilibrium assignment model. The proposed model consists of a nested logit model aiming at the improvement of prediction accuracy of the national expressway network, and the structure of simply presuming the log sum use of local roads in the conversion ratio calculation. Moreover, it examines the setting of route choice options in consideration of the difference of expressway use characteristics and the present toll discount policies by area. It is checked that the prediction accuracy of the model is good. Finally, the paper also proposes a model corresponding to toll free policy of the existing expressways with the OD data of the expressway use obtained from the application of a toll-free expressway pilot program in 2010 when a road traffic census was also conducted.
The heterogeneity of the deterioration rate of infrastructure is attributable to various factors. In this study, the authors propose a mixed Markov deterioration hazard model considering the heterogeneity of deterioration rate due to technical problems in construction and the heterogeneity due to management problems. In detail, an ideal deterioration process is expressed with a Markov deterioration hazard model excluding the effects of the deterioration caused by the management environment. In addition, the gap between the current deterioration process and the deterioration process that would become the best practice under certain technical conditions is expressed by using management efficiency parameters. Then, the effects of construction and management on deterioration rate are evaluated quantitatively, through the efficiency evaluation based on probabilistic frontier analysis. Lastly, the authors discuss the usefulness of the method proposed in this study, by carrying out the case study of the method to inspection data on sewer culverts.
In this study, the authors develop a deterioration prediction model with respect to deterioration management indicators by using continuous variables. Quite a few deterioration management indicators of infrastructure are observed as continuous values. It is possible to discretize these continuous values and predict deterioration with a Markov chain model, but in order to obtain more precise deterioration prediction results, it is desirable to develop a direct model of the time variation in continuous values. In this study, the authors formulate a continuous deterioration hazard model including characteristic variables that vary according to the structural characteristics and environmental conditions of infrastructure, and propose a Bayesian estimation method using the Markov Chain Monte Carlo method. Furthermore, the authors attempt to empirically analyze the applicability of the methodology proposed in this study.
This study develops a spatial computable general equilibrium model that considers agglomeration economies and mobility of production factors, including labor and capital. To this end, we extend the new economic geography models of industrial location and agglomeration with factor mobility. We then present parameter estimation and calibration procedures and an approach for obtaining the stable equilibrium that emerges with changes in structural parameters. Applying these methods, this study quantifies the effects of the trade cost reductions in Japan to clearly describe characteristics of the developed model.