This paper presents the deformation characteristics of sandy soil specimens developed in wetting and drying processes. A series of triaxial tests was carried out on Toyoura sand and some silty sands, when the tested material is subject to wetting/drying cycles, under the constant confining pressure of 50kPa. During these processes, small cyclic loading tests were performed in order to obtain small strain stiffness of the materials. Throughout the test, volumetric, axial and radial strains were measured and the amount of water flowing in/out of the specimen was monitored. It was found that the deformation of silty sand was highly affected by the wetting/drying cycles, whereas Toyoura sand did not show noticeable changes. For silty sand, volumetric strains were developed positively throughout the first wetting process as well as the successive drying and repeated drying/wetting stages. The presence of fines appeared to play an important role in collapse behaviour of sandy soil, even though the fines content was only 3%. Small strain stiffness seemed to be also affected by the wet/dry condition, but the change in small strain stiffness could not be well explained by the change of density and suction of the material, which indicates that the internal structure of the material was altered due to the collapse occurred in the first wetting cycle. [This abstract is not included in the PDF]

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A ground cave-in tends to happen above and around a buried structure. It is assumed that the permeability at the interface between a structure and the ground may be higher than that in the ground, causing the formation of water pathway at the interface. Such water pathway may be a trigger for the further subsurface erosion, which accelerate the formation of cavity and loosening in the ground.
In this study, a series of model test was conducted to investigate the effects of a buried structure on the formation of water pathway and ground loosening. It was observed that ground loosening and cavity tended to occur around a buried structure, probably because the structure seemed to alter the path of seepage water. [This abstract is not included in the PDF]

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A trapped air in the ground can be a trigger for the local failure of the ground when the air pressure is elevated. Especially a subsurface cavity may have large effects of such phenomenon. In this study, fundamental experiments were conducted to investigate the effects of local collapse due to the rise of trapped air pressure. The water was penetrated from bottom or surface of the cylindrical sand specimen, causing the local rise of pore air pressure. In some cases, the soil specimen completely failed due to the elevated air pressure. [This abstract is not included in the PDF]

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A new technique of ground improvement by microbial function has been recently proposed, as more eco-friendly technique than conventional one. Metabolic function of microbes produces carbon dioxide, which helps to generate calcium carbonate. Such a cementation process may be operated repeatedly as long as microbes’ function is active. In this study, a series of triaxial test was conducted in order to evaluate the recovery of shear-damaged cementation generated by those function in Toyoura sand specimens. It was found that stiffness of the bio-cemented specimen degraded by shear but it recovered when the microbes in the specimen were activated by grouting. [This abstract is not included in the PDF]

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    RC slabs extracted from an open-type wharf were tested in order to evaluate the relationship between visually judged deterioration grades and load carrying capacities. Based on the statistical analysis on the relationship between deterioration grades and load carrying capacities, the probabilistic evaluation method of the load carrying capacities of RC members was proposed as quantitative evaluation method of residual structural performance of existing port RC structures. [This abstract is not included in the PDF]

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        There are many life cycle scenarios for ensuring structural performance of civil infrastructure that include when and how suitable repair would be carried out. In this study, life cycle scenarios for an open-type wharf were setup and evaluated based on the LCC. The failure probability against seismic action was calculated taking into account the variability of corrosion of steel piles. When the failure probability reaches to its limit value, repair is taken of which costs are counted in the LCC. Through the comparison of LCC, the most feasible life cycle scenario was discussed. [This abstract is not included in the PDF]

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        When deicing agents are spread in concrete under freeze-thaw environment, chloride ions from deicing agents are transported into concrete, which may accelerate frost damage. However, the interaction of chloride ion and frost damage has not been made clear. This study investigates transportation of chloride ion from deicing agents in frost-damaged concrete. The total chloride ions and the soluble chloride ions were measured in the experiment and chemical compositions of various forms of chloride were investigated by using X-ray diffraction techniques. [This abstract is not included in the PDF]

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        We developed technologies to collect site environment parameters (ex. surface temperature, period of flooding, and terrain condition) and to create a site environment map that shows the diversity of site environment conditions of Amazon River basin. The filtering method “kalmfit” and a discrete time-series modeling method were applied to the 8-days composite of MODIS dataset for removing the influences of clouds and other noises on the data set. Data sets consists of NDVI, NDII, day/night brightness temperature and spectral clusters dataset in 2001 to 2009 every 8day intervals. A methodology for classification of a site environment conditions were developed. The terrain data derived from digital terrain model were also introduced and a site environmental map with 500m resolutions was created. [This abstract is not included in the PDF]

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        This study aims to assess spatial patterns of exhaust emission PM_2.5 over Asian mega cities with satellite remote sensing and city tra.c modeling. Firstly, aerosol optical depth (AOD) were estimated with MODIS satellite images. Secondly, exhaust emission was modeled by the number and types of cars, exhaust emission .ux of cars, and population density. Thirdly, the temporal patterns of AOD from satellite remote sensing and exhaust emission estimation based on city tra.c modeling was investigated over Asian mega cities. Finally, exhaust emission PM_2.5 is evaluated by anthropogenic BC inventory dataset. As a result, it was found that distribution maps of AOD derived from MODIS have consistency with that of PM_2.5 calculated from tra.c modeling is similar. However, exhaust emission PM_2.5 is not completely similar to anthropogenic BC data quantitively. [This abstract is not included in the PDF]

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        Information about the biophysical parameters of plants is useful for the prediction of growth, yield, rotation cycle, carbon sequestration and management practices. In this study, we have investigated different biophysical parameters of cashew and rubber plants using Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar (ALOS/PALSAR) backscattering properties in Cambodia. The result shows the plants’ structural dependence on PALSAR data. The backscattering coefficient (σ⁰) has different response for both plantation types because of differences in their biophysical parameters. This dependency of σ⁰ shows different behaviour of PALSAR dual polarimetric data. The σ⁰ HV polarization shows fairly good correlation with the biomass, height, DBH and age of cashew and rubber plantations up to the saturation limit. [This abstract is not included in the PDF]

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        Rear-end collision occupies about half of the causes of the total accidents in Metropolitan Expressway in Tokyo, and it is important to analyze accident risk in a microscopic way in order to make effective countermeasures for rear-end collisions. This study analyzed traffic flows immediately before an accident in detail using pulse data from traffic detectors, and identified conditions which may lead to an accident. Then a method to forecast this situation from observed data in advance was proposed and the effectiveness of the method was confirmed. [This abstract is not included in the PDF]

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        As a preliminary investigation, the possibility of introducing housing water tanks to store rainwater for improving urban environment and disaster risk reduction was explored. Firstly, the effect for introducing housing water tanks to store rainwater and its evaluation indexes were examined in terms of quantification. As a result of several analysis, the validity of introducing housing water tanks to store rainwater was demonstrated, however the proposed formula and result of our evaluation still needs to be further considered due to many assumptions and simplification. [This abstract is not included in the PDF]

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        In this study, the authors tried to extract papers related to disaster prevention from academic papers and analyze the trends of academic research on disaster prevention. Specifically, the authors took five steps, “Constructing academic papers database”, “Constructing keywords database corresponding to disaster event, countermeasures phase, and affected by the disaster event”, “Extracting academic papers on disaster prevention”, “Calculation of the distribution of research field on disaster prevention”, and “Comparative analysis of trends in research” [This abstract is not included in the PDF]

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    University is an institute for development of bearers of future and conducting leading-edge research. In university, there are much valuable data and precious documents. So disaster countermeasures are essential for university. The authors tried to construct Service Continuity Model (SCM) of university in preparation for emergency. The purposes of SCM are three points, damage minimization at university in emergency, proper continuity of important service of university, and contribution to residents living in the vicinity of university. In this paper, outline of SCM workshop and result of the workshop in a university are reported. [This abstract is not included in the PDF]

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        The present study aims to reduce the load of the caring activities of the medical personnel for senior citizen&rsqup;s lifestyle using the remote monitoring system of their lifestyle. This system can detect the accident and immediately send the information to the family and the medical personnel, and also support a continuous monitoring of their daily activities. This paper presents the experimental results obtained from the monitoring of the usage condition of the refrigerator (opening and shutting time and frequency), rest rooms and bed (the time of going to bed and getting up). As a result, each of the refrigerator, the rest room, and the getting up situation showed the life pattern and be able to recognize the unusual pattern. [This abstract is not included in the PDF]

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        This research developed an IT triage system (TARCY) for collecting disaster medical information in real time and sharing it among related institutions in entire area. FeliCa card and card-reader are used as a part of this system to obtain the number and condition of patients in real time. A disaster drill was held at the Shizuoka prefecture hospital. TRACY was examined for its applicability and practicability during this drill. The result shows that the present system can obtain the number of patients for each triage level and the accepted number of patients in each diagnosis and treatment department in real time. [This abstract is not included in the PDF]

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        This research developed an IT triage system (TARCY) for collecting disaster medical information in real time and sharing it among related institutions in entire area. This system was used in the disaster drill held at the Shizuoka prefecture hospital. The applicability and practicability of TRACY was examined by the entire evaluation meeting and the meeting with the main triage officers held after the triage drill. This paper presents the result of the feedback and opinions obtained from these meetings. [This abstract is not included in the PDF]

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        The concept of Information Sharing Platform among various organizations for achieving prompt disaster response is recently discussed and supporting technologies are being developed. In this research, information system for supporting disaster medical response by information sharing between existing systems in hospitals was proposed. System was designed based on data flow charts showing flows of necessary information through disaster medical responses. The effect of the system was evaluated by comparing the efficiency of medical responses before and after sharing information. [This abstract is not included in the PDF]

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        We have continued the activities on flood risk awareness-building and countermeasure studies with citizens in Shinkoiwa North District since 2006 fiscal year. However, the expansion of activities got slow because the participants were only elderly persons from local communities and existing risk communication tools lacked versatility. To solve these problems, we developed new risk communication tool and made local self-governing educational program for understanding flood risk. Additionally we set up workshops for junior high school students based on the educational program. [This abstract is not included in the PDF]

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        In this study, we focused on possibility of long-distant evacuation by railways in case of flooding of the Arakawa River in Tokyo. We developed an evacuation simulation system to analyze it. As result, we found that the evacuation has high difficulty. As the reasons we can point out that the transportation capacity for railways is relatively small for amount of evacuees and that the tens thousands of evacuee waiting for a train appears in or near a station and it cannot be uncontrollable. We have to grasp the capacity of other transportations such bus and walk and possibility of stay in a building, and find the feasible evacuation plan with combination of various transportations. [This abstract is not included in the PDF]

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   Situations of earthquake disaster reconstruction would vary depending on characteristics of the region, community, social and economic conditions. This paper proposed a new method of imagination training for the situations of post-disaster reconstruction developed by the joint research in Saitama. The advantage of this method is to make effective use of imagination of workshop participants through the viewpoint of both disaster victims and administrative staff to think of both the recovery of living conditions and the reconstruction of physical environments. And this paper also considers the reconstruction scenarios and problems after the great earthquake in the Tokyo metropolitan region in the future.

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        Earthquake occurred in off the Pacific coast on March 11^th, 2011. Extensive damage caused by the earthquake in the area of Kanto and Tohoku. In this paper, we’ll introduce the acceleration record observed in IIS and disaster situation in IIS. IT accelerometer which is attached in basement measured 129.82gal in East-West direction. Instrumental seismic intensity was 4.6. Proper period was 0.52 seconds in N-S direction and 0.58 in E-W direction. [This abstract is not included in the PDF]

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        IIS started advanced use of earthquake early warning since Feb. 24, 2010. Earthquake early warning is broadcasted inside buildings An, As and B-F in case that strong tremor with intensity more than 3 is expected to arrive at Komaba campus. At the 2011 off the Pacific coast of Tohoku Earthquake at 14:46 on March 11, 2011, IIS received the ninth early warning information at 14:47:2 and successfully broadcasted it about one minute before the arrival of shear wave in IIS. A questionnaire survey was done after the earthquake for evaluating the effect of the warning. [This abstract is not included in the PDF]

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        After the tsunami of Sumatra earthquake in 2004, installation of tsunami warning system in Indian Ocean was proposed by international communities. But, it is difficult for Indian Ocean Rim countries, with less resource, to install technologies similar to that of Pacific Ocean. Therefore we proposed “Tsunami Warning System Using Multi-Purpose Maritime Observation Buoy Network” in this research. This report shows that the proposed buoy system could observe and detect the tsunami in case of the tsunami in the 2011 off the Pacific coast of Tohoku Earthquake. [This abstract is not included in the PDF]

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        It reported on the result of having executed the tsunami damage investigation due to the 2011 off the Pacific Coast of Tohoku Earthquake that had occurred at 14:46 March 11, 2011 after two weeks. The feature of the tsunami damage is thought to be two roughly separately. First one is the resident who lives in the high ground doesn’t have damage at all. Second one is the extensive damage from the storm is caused in the timbered house. These findings study thoroughly in disaster prevention engineering and give an important suggestion. [This abstract is not included in the PDF]

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        The damage investigation of the damaged area of Sanriku railway and hearing to the Sanriku railway president were executed due to the 2011 off the Pacific Coast of Tohoku Earthquake As a result, it extended to whole line and the extensive damage from the storm was confirmed. Moreover, it was able to be confirmed that the Sanriku railway was a necessary, indispensable railway as place along railway-tracks resident and victim’s transportation. However, the way until restoring severity as had it to install more than the imagination and to install the restriction in operation by the disconnection of the large generation mainly of the “Minami Riasu“ line such as the station, the bridge, outflows of the fill and the signal systems etc. were damage became clear. [This abstract is not included in the PDF]

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        In Japan, several big earthquakes are expected to occur in the near future. A lot of structural damages due to these earthquakes will cause enormous needs for building damage assessment. However, current number of human recourses who are trained with the procedure of building damage assessment is not enough. It is necessary to increase the number of investigators before a next event. In this research, propose and practice for building damage assessment using Excel VBA techniques. [This abstract is not included in the PDF]

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        In the 2011 off the Pacific coast of Tohoku Earthquake, there were some problems in the media reports such as concentration on specific municipality and the high emphasis on the nuclear power accident and so on. Many media reports couldn’t contribute through appropriate disaster journalism in disaster management cycles. The purpose of this research is to develop appropriate Media Model which can contribute for effective disaster assessment in disaster management cycle. This paper shows the results of the comparison of the contents of TV program and the damage of the municipality in 10 days after the earthquake occurrence. [This abstract is not included in the PDF]

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    In the 2011 off the Pacific coast of Tohoku Earthquake, there were some problems in the media reports such as concentration on specific municipality and the high emphasis on the nuclear power accident and so on. Many media reports couldn’t contribute through appropriate disaster journalism in disaster management cycles. The purpose of this research is to develop appropriate Media Model which can contribute for effective disaster assessment in disaster management cycle. This paper shows the results of the comparison of the contents of WEB news and the damage of the municipality in 10 days after the earthquake occurrence.[This abstract is not included in the PDF]

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        There are mineral-rich hydrothermal deposits around of the seabed in Japanese exclusive economic zone (EEZ). For securing of mineral resources in Japan, a precise investigation and estimation technique is highly emphasized.
Our group has studied a new exploration technique to evaluate the distribution of underwater layer structures of the hydrothermal deposits using “Mils-Cross” method with a low-frequency acoustic source deployed into the autonomous underwater vehicle (AUV) which is running at a low-altitude near the sea bottom.
In last researches, our group developed a prototype low-frequency acoustic source, and confirmed that this source is useful to acquire the sub-bottom profiling data under the bottom of Hitachi-Tone river by executing a performance test.
Based on these results, we developed a prototype deep-water acoustic exploration system to find out the layered structures under the actual hydrothermal deposits.
We deployed our prototype system into the deep-water exploration towed body “Deep-Tow” that is installed into the research vessel “Natsushima, ” and implemented a cruising test to acquire the actual acoustic data under the hydrothermal deposits in the East-China Sea.
After some analysis using these data, we confirmed that our prototype system can acquire the layered structures under of the sea-bottom and sub-bottom profiling data around the hydrothermal deposits.[This abstract is not included in the PDF]

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