The decisions on the collective evacuation order by the mayor for the municipality's citizen faced with disaster crisis can be formulated as meta-decisions on changes in decision modes from the normal mode to the crisis one. Given deep uncertainty of disaster processes, the disaster mitigation plan prepared in advance can only provide a benchmarking scenario on how the local citizen and government respond to the probable disaster scenarios, which is to be shared commonly by the people concerned. However, during the crisis period when the disaster is actually processed, the mayor is highly required to judge whether the on-going disaster process can be maneuvered by the set of predetermined rules described in the plan, or not. If not, she shall implement the contingent emergency rule for the on-going unforeseen disaster process. This paper proposes a model for designing the benchmarking evacuation rule for volcanic disasters, which also enables to detect systematically extraordinary contingencies where exceptional evacuation rules are necessary. In addition, the proposed model is applied to the actual case of Mt. Usu in Hokkaido, Japan.
Transfer scaling method utilises both a larger data from older time point and a smaller data from more recent time point. A use of only the smaller data from more recent time point, however, reportedly produced better forecasts than the transfer scaling. This study analyses usefulness of the transfer scaling focusing on data collection time points and the numbers of observations. In any combinations of time points and the numbers of observations, the transfer scaling never produced statistically significantly better forecasts than the model using data from only the more recent time point. The transfer scaling method has advantages in cases where the number of observations from the more recent time point is substantially small; it produced better forecasts on average with smaller variance, and it is less likely to produce poor estimates and forecasts.
Several approaches to reduce the social damages due to water suspension in disasters are classified roughly into the approaches of “demand side” and “supply side”. This study focused on the approaches of “demand side”. The approaches of “demand side” are a management to stabilize the water supply-demand balance by demand adjustment that corresponded with the water supply capacity degradation at the time of a disaster. In particular, this paper proposed a method of “Water Demand Management for Disaster Preparedness (WDMD)” through “risk communications”. First, the authors have become clear the structure of “water demand in disasters (WDD)”, which depends on the “water suspension tolerable limits (WTL)”. Next, to increase the WTL, namely, to manage the WDD, a psychological model to prompt the awareness, the understanding and the solutions of water suspension risk through communications by water supply utilities was constructed. Last, to verify the validity of the model, the authors conducted several communication experiments on 600 urban residents, and this experiments also indicated that the rate of increase of WTL changes due to the difference in communication methods and information contents. Furthermore, the success of the risk communications was indicated the possibility of being effective for fostering awareness of “mutual-help” (to share own tap water with residents in water suspension areas).
Theoretical studies of new economic geography models in one-dimensional geography such as racetrack and line segment have revealed two regularities for spatial distribution on population. First, population agglomerations are evenly spaced, i.e., spatial periods emerge. Second, a monotonic decrease in transportation costs results in a gradual increase of the spatial period which at last leads to a unimodal distribution. In this paper, these theoretical findings are quantitatively assessed by a spatial spectrum analysis of the Population Census data of Japan. An emergence of spatial periods in the population data at multiple time periods is detected by strong power spectra. By comparing the power spectra at different time periods, it is also shown that the spectrum for the unimodal pattern has monotonically grown over time. It is argued that these properties are consistent with theoretical prediction.
This study examines the effects of location-dependent parking fees and time-varying congestion tolls on the behavior of heterogeneous commuters and their commuting costs. To this end, we develop a model of departure time and parking location choices by heterogeneous commuters and characterize its equilibrium. By comparing the equilibrium with and without pricing policies, we obtain the following results: 1) without pricing policies, interactions among heterogeneous commuters yield an inefficient distribution of trip timing and parking locations; 2) imposing a parking fee and expanding parking capacity may concentrate the temporal distribution of traffic demand, thereby exacerbating traffic congestion and total commuting cost; 3) the social optimum is achieved by combining a parking fee with a congestion toll; and 4) the revenue obtained from pricing of parking and roads exactly equals the costs for optimal parking and bottleneck capacity; that is, the self-financing principle holds in the model.
This study conducts spatial computable general equilibrium (SCGE) analyses that consider agglomeration economies and workers' relocation. To this end, we modify the SCGE model developed by Takayama et al.1) to introduce intra-regional transportation costs. We then examine the effects of changes in transportation costs on the spatial distribution of workers in Japan and show that the prediction of the model is roughly consistent with the data. In addition, we demonstrate through an example that hysteresis phenomena can be observed in the model.
This study aims to quantify the influence of accessibility of outdoor play space on children's play behaviour by focusing on open space and frequency of two different types of play. A retrospective questionnaire survey on play environment in ages 9-10 was carried out on junior high school students. Correlation analyses between accessibility of open space and a) ball-game frequency and b) digital sports games frequency are conducted. Participants are classified by indoor-outdoor preference and physical-digital preference. The results were as follows: a) physical-digital preference is determined mainly by preference for active play and the appeal of digital play, b) accessibility of open space influences daily ball-game frequency in the indoor-digital preferring group, c) correlation between preference for ball-game and preference for digital sports game can be observed, d) digital sports game play increases as accessibility declines in the outdoor-physical preferring group.