ACCESS TIME OF EMERGENCY VEHICLES UNDER THE CONDITION OF STREET BLOCKAGES AFTER A LARGE EARTHQUAKE

The previous studies have been carried out on accessibility in daily life. However it is an important issue to improve the accessibility of emergency vehicles after a large earthquake. In this paper, we analyzed the accessibility of firefighters by using a microscopic simulation model immediately after a large earthquake. More specifically, we constructed the simulation model, which describes the property damage, such as collapsed buildings, street blockages, outbreaks of fires, and fire spreading, and the movement of firefighters from fire stations to the locations of fires in a large-scale earthquake. Using this model, we analyzed the influence of the street-blockage on the access time of firefighters. In case streets are blocked according to property damage simulation, the result showed the average access time is more than 10 minutes in the outskirts of the 23 wards of Tokyo, and there are some firefighters arrive over 20 minutes at most. Additionally, we focused on the alternative routes and proposed that volunteers collect information on street blockages to improve the accessibility of firefighters. Finally we demonstrated that access time of firefighters can be reduced to the same level as the case no streets were blocked if 0.3% of residents collected information in 10 minutes

APPLICATION OF CELL PHONE STATISTICS FOR ESTIMATING STRANDED PEOPLE BEHAVIOR AFTER SEVERE EARTHQUAKE IN TOKYO

In this paper, we present a walking home simulation as anticipated after a large earthquake, and analyze people’s behaviors, walking and stopping, including the crowding of facilities by those unable to walk all the way home. For creating the necessary data for this simulation, we construct a method to estimate the spatiotemporal distribution of people with detailed individual information such as sex-age classification, and home location, by assembling population distribution data (Mobile Spatial Statistics and Person Trip survey data). The walking home simulation results verified significant variations in the crowding of facilities for stranded people due to differences in the day of the week and the time of the earthquake. Locations in Tokyo with insufficient numbers of facilities for stranded people were identified and some spatiotemporal characteristics of crowding, such as changes in crowding with time elapsed since the earthquake, were described

INFLUENCE OF WORD-OF-MOUTH COMMUNICATION ON LARGE-SCALE EVACUATION AFTER A SEVERE EARTHQUAKE

Physical disaster in a serious earthquake (fires and street blockages), word-of-mouth communication (WOMC) among evacuees, and evacuation behaviors are modeled, and an evacuation behavior simulation is carried out. The influences of WOMC regarding the information about disaster and the locations of evacuation areas on a large-scale evacuation are observed. The simulation results demonstrate some new findings and highlight the importance of providing guides in tourist areas, where there are many people who have limited local geographical information. It is also shown that once false information has appeared in the process of WOMC among the wanderers, especially in locations with a high density of wanderers, the false information will spread quickly among the evacuees by WOMC and can negatively influence a large-scale evacuation

ACCESSIBILITY ASSESSMENT OF EMERGENCY VEHICLES IN TOKYO METROPOLITAN AREA AFTER A LARGE EARTHQUAKE

At the time of a large earthquake, property collapse (e.g., building collapse and street blockage) will obstruct emergency activities (e.g., firefighting activity and ambulance service) and cause the expansion of secondary damage. For reducing the secondary damage of a large earthquake, it is important to assess the accessibility of emergency activity under property collapse. However, the accessibility index, which can evaluate the emergency activity considering the effect of property collapse, is not developed nor applied in actual urban area. In this paper, we propose the street network accessibility: indices of assessing the movement of emergency vehicles. Then, we construct a simulation model that describes property collapse and the movement of emergency vehicles. Performing the simulation in Tokyo Metropolitan Area, we evaluate the damage of each building/street and assess the street network accessibility after a large earthquake. Finally, analysing the relationships among indices, we indicate that it is important to evaluate the street network accessibility from multiple viewpoints

Classification Methods for Spatial Data Representation

In the process of representing quantitative spatial data on a map, it is necessary to classify attribute values into some class divisions. When a number of classes are employed, the characteristics of spatial distribution of original data can be expressed faithfully. However, its legends might become rather complicated and the delicate color differences in the represented map would be difficult to distinguish. On the other hand, when employing a few classes, the information such as small vibrating factors or local peaks might be ignored, namely, much information of original data will be lost. Hence, we should discuss how many classes are necessary to represent spatial data. Furthermore, even if the same spatial data are represented using the same number of classes, we might obtain the quite different maps according to the choice of classification methods incorporated in existing geographic information systems. Namely, the characteristics of the original data might be overlooked, or there might be a risk of mistaking judgment, if we do not have enough knowledge about classification methods as well as the nature of original data. Hence, we should also discuss how the boundary value between each class should be set. In this paper, a new classification method using an evaluation function based on Akaikeis Information Criterion is proposed, and is applied to actual spatial data. Next, based on the consideration about its result, another classification method minimizing information loss of original data is proposed. Furthermore, numerical examples of its applications are achieved through the comparison with existing classification methods

Brand Value of Area-Images Extracted from SpatialDistribution of Building Names

Our area-images are composed of evaluations derived from the various kinds of elements or activities within different regions. In quantitative terms, the extraction of area-images is difficult. In this paper, we focus on a phenomenon in which a part of peopleis area-image can be observed in the names of buildings. In the first instance, a model based on the random utility theory is constructed to describe the spatial distribution of building names. Secondly, the proposed model is calibrated using actual data from the city of Tokyo (Setagaya Ward), and effects of such area-elements or activities on area-images are then estimated. Finally, values for the area-images are quantitatively estimated and their spatial distribution is represented on a map.

A Model of Land use Conversion and Its Application

A quantitative model for analyzing the spatial distribution of land use utility is proposed. This model is based on the random bidding theory in which location behaviour is decided according to the size of utility to be obtained. The utility function used here consists of the benefit and the cost in the process of land use transition. The benefit is described as the positive utility that can be obtained by doing the corresponding land use at the place. The cost is described as the negative utility that is necessary for changing the land use from one state to the others. The most likelihood method is generally employed to estimate the parameters of this kind of models. However, we attempt to propose the other statistical method through the mathematical consideration. Using this model, it is possible to obtain the spatial distribution of land use utility that differs with the places and with the land use states. We can also evaluate the effects of a change of land-price or construction costs on our utility. Namely, our location behaviour can be estimated numerically relating with the social or economic factors. As numerical examples, we apply the proposed model to the actual land use data and access the effectiveness of the model

A Method for Estimating Land Use Transition Probability Using Raster Data - Considerations about apatial unit of transition, fixed state of locations, and time-varying probability

In the field of urban and regional planning, several Markov chain models for land use conversion have been proposed. However, some problems have been encountered when estimating land use transition probabilities. In this paper, a new estimation method to determine land use transition probability is proposed by taking into account spatial units of land use transition, fixed state of locations, and varying transition probabilities. The effectiveness of the proposed methods and some new findings on land use conversion are presented using numerical examples

Use of the area-dividing method to minimise expected error in land-use forecasts

Employing Markov chain models to predict the distribution of land uses is always plagued by several types of error. One type of error stems from the uncertainty which always resides within the transition matrix. In this paper we therefore present a method for estimating such error and for minimising it. As each matrix coefficient refers to one subarea, error is related directly to how the subareas are formulated, and so our method involves dividing a whole region into more appropriate subareas. A simulated neural network is used to achieve this division optimally. We report how experiments were run within an actual urban area. It was found that land-use prediction error is indeed minimised whenever the area-dividing method is used.

Aerial photogrammetry procedure optimized for micro uav

This paper proposes the automatic aerial photogrammetry procedure optimized for Micro UAV that has ability of autonomous flight. The most important goal of our proposed method is the reducing the processing cost for fully automatic reconstruction of DSM from a large amount of image obtained from Micro UAV. For this goal, we have developed automatic corresponding point generation procedure using feature point tracking algorithm considering position and attitude information, which obtained from onboard GPS-IMU integrated on Micro UAV. In addition, we have developed the automatic exterior orientation and registration procedure from the automatic generated corresponding points on each image and position and attitude information from Micro UAV. Moreover, in order to reconstruct precise DSM, we have developed the area base matching process which considering edge information. In this paper, we describe processing flow of our automatic aerial photogrammetry. Moreover, the accuracy assessment is also described. Furthermore, some application of automatic reconstruction of DSM will be desired