This research studies air flow of a wave power device by extension of numerical wave tank code CADMAS-SURF. To simulate air flow in the water oscillation chamber, airflow analysis program is linked to CADMAS-SURF. Energy conservation equation of the gas and Bernoulli equation for the nozzle flow are solved to estimate the pressure and air flow. The numerical results are compared with experimental results in terms of reflection characteristics of the incident waves from the air chamber, and water level and pressure variation in the air chamber, showing fair agreement overall.

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 Offshore wind farms have not yet been realized in Japan except for some near-shore plants although they are promising for sustainable economic growth with less CO₂ emission. This paper introduces a marine condition study for offshore wind farm design, using simultaneous data of waves and winds obtained by GPS buoys used in NOWPHAS (Nationwide Ocean Wave information network for Ports and Harbors), in order to clarify the offshore wind turbulence characteristics. Values of offshore wind turbulence coefficient defined as the ratio between the standard deviation of wind speed variation and the average wind speed are smaller than those of onland one.

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 This study describes a novel system of compressed air generation using a floating wave energy converter installed in a coastal defense structure. The system produces compressed air instead of electricity. This is because it is not desirable to convert wave energy directly into electric power in large amounts due to both low energy conversion efficiency and the consequent irregularity of the electric output. Compressed air is easy to store and safe to use in coastal areas. The objective of this study is to understand how much energy from the incoming waves can be captured for use by the system. Laboratory experiments were carried out to determine the effects of wave and system load conditions on energy conversion efficiency and hydrodynamic characteristics for the system. The test results show that the system can operate with a high degree of efficiency under loops of the standing wave formed in front of a structure. A reduction of wave reflection can be achieved by the system under a wide range of wave conditions.

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 The applicability of autonomous metal hydride actuator (A-MHA) as the equipment for seawater exchange is verified through field experiment and numerical simulation. The Mm-based alloy obtained by a laboratory test shows the performance of hydrogen desorption-absorption and the durability of alloy are improved in comparison to LaNi₅ metal hydride. The pumping discharge due to A-MHA using the alloy is about 30m³/hr and the anoxic water mass near the seabed is controlled. The requirement of seawater exchange with A-MHA is analyzed by using the Lagrangian particle model. At a minimum, the discharge of A-MHA requires more than 60m³/hr.

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 Wind data are fundamental and indispensable information for the design of wind power facilities. Cup anemometers are classical tools but still now widely used practically for measuring wind. However, it should be noted that the cup anemometer has a mechanical rotation system which has poor response behavior in the fluctuating wind.
 In this report, frequency response performance of cup anemometer is studied. A linearized model for the cup anemometer is proposed for describing its power attenuation in the high frequency dynamics. The model is verified by numerical simulation and compared with real field wind data using spectrum analysis. A simple compensation method of cup anemometer is also proposed to improve its dynamic performance.

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 Water temperature distribution in enclosed water area, especially from water surface to 0.5m under water surface, was measured with weather information, wind, solar radiation. Seasonal change of vertical thermal distribution including violent weather effect is presented.Based on the measurement data, latent heat flux and sensible heat flux are estimated. Moreover thermal diffusivity in the water surface layer with 0.5m depth is evaluated. Finally, thermal flux between water surface and atmosphere is discussed with considering thermal supply from deeper water to water surface.

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 Using SDP (Surface Data Product) wind data acquired at on-land meteorological stations, Yamaguchi et al.(2009) made data sets of hourly sea surface wind distributions over a 45-year period in Tokyo Bay, Ise Bay and the Seto Inland Sea. Time variation of wind speed and direction at coastal or sea stations in a storm is compared between computation and measurement for each of the measurement data-available stations during many storms, in cases where the error evaluation is represented by 7 indices such as correlation coefficient and so on. Frequency distribution of individual error index is made by collecting the results for all station-storm cases and statistics are obtained. The same procedure is taken for hindcast wave height data. Overall investigations of the error statistics reveal that data sets of the estimated winds and wave heights are acceptable products for practical use.

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 Shallow water wave hindcasting for each of around 100 intense storms (typhoons and low pressure systems) in the past 45 years from 1961 to 2005 is attempted independently in Tokyo Bay and in Ise Bay. Marine wind distributions are obtained using the SDP wind data acquired at on-land meteorological stations around Tokyo Bay and Ise Bay respectively. An extreme value analysis is conducted to obtain 50-year return wave height H₅₀ in both bays. Comparison between hindcasts and measurements is made for not only the time-varying wave height and its peak wave height during a storm at several stations but also for the H₅₀. Results show that the wave model yields generally reasonable estimates. In Tokyo Bay, a 3 m contour line of the H₅₀ with the maximum of 4 m covers a wide area and in Ise Bay, a 4 m contour line of the H₅₀ with the maximum of 5.5 m spreads over a wide area.

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 High-accuracy weather forecast is established and applied to Eco-shipping system. Traial navigationn experiment was demonstrated for 7 domestic vessels. Eco-shipping system shows reasonable and sufficient efficiency of FOC saving (CO₂ emission reduction).

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 We developed a new shipping scheduling technique specialized for carrying barges using marine forecast by applying existing 'weather routing technique'. This scheduling technique simulates the movement of barges to search the optimal routes under the whole conditions, such as positions of carrying barges, marine forecast, the number of barges in the way port, load capacity, barge speed, wave height limit and wind speed limit to navigate barges, the position of way port, operating time to take up or drop off loads and permitted working hours. To shorten the simulation processing time, we prepared candidate route pattern database in advance. According to some case studies, the validity of this technique was verified to make a plan of the optimal barge group, to secure the increase of total load in comparison to the empirical scheduling as well as to estimate the seasonal variation of capacity factors.

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 In marine works, it is important to get wave prediction results for safety operation and work executable judgment. Recently, the advanced wave prediction method using the WAM model has been utilized generally in marine works. However, the accuracy of the wave prediction results is not clear in marine work conditions.
 In this study, from the comparison with the WAM model prediction results and the wave measurement results, we discussd the accuracy of the wave prediction results for marine works in the SETO Inland Sea. As a result, the optimum conditions for the WAM model prediction is clear.

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 The wave observation on the Japanese coast through the Nationwide Ocean Wave information network for Port and HArbourS (NOWPHAS) has been conducted since 1970. The wave data were accumulated for 30 years or longer at the 20 observation sites or more. According the former research, it is difficult to find a high correlation between the wave statistics, such as, the mean and maximum significant waves, and the storm frequency, at an observation site and climatic indexes, such as SST, PDOI, NPI, SOI, AOI, and the typhoon genesis and landfall frequencies. This study, therefore, divided the 24 observation site into three regions on the Sea of Japan and four ones on the Pacific Ocean. Then, this study examined the correlation of the wave statistics at each region with the climatic indexes. The major conclusions are as follows.
 (1) The mean significant wave height has the highest correlation with SST among these climatic indexes.
 (2) The correlation of the mean significant wave period with the climate change indexes is higher than that of the mean siginificant wave height.
 (3)The correlation of maximum significant waves with the climate change indexes is low except for the typhoon landfall frequency.
 (4) The correlation of the frequency of major storm events with the climate change indexes is low except for the typhoon landfall frequency and SOI.

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 To understand synoptically wave conditions for the ship navigation in the North Pacific, we examine the relationship between the middle and long term variations of significant wave height (SWH) in the North Pacific and the climate index (NPI: North Pacific Index) which is one of the representative climate indexes. The correlation coefficients between SWH and NPI during all the data period tend to be significantly high in the NPI region (30°N-45°N, 160°E-140°W). The correlation coefficient between the area-averaged SWH and NPI in the NPI region is also significantly high. In winter, the correlation coefficient between SWH and NPI is high in the NPI region expect its northwestern region. In spring, the correlation coefficients tend to be low in the whole region of the North Pacific. In summer, the correlation coefficients tend to be high in the northern half of the NPI region and the offshore region between the Aleutian Islands and Canada. In autumn, the correlation coefficients tend to be high in the region between the NPI region and the eastern offshore region of Japan. The correlation coefficients between the area-averaged SWH and NPI in the western, eastern and northern sides of the NPI region tend to be low in spring and high in autumn, respectively. On the other hand, in winter and summer, the correlation coefficients are scattering significantly in each sides.

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 This paper outlines the existing system for prediction of ocean waves, and constructed a new model based on an advanced WAM model. Then we created a new database of prediction of ocean waves, which compared with the observation results and analyzed to confirm its precision. In addition, we prepared a basis for selecting the right place to allocate offshore wind farms as an example.

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 This paper discusses a spatial distribution of the maximum wave height in the 3 sub-areas of the Seto Inland Sea for each of the 26 big typhoons in all specially selected during the 1918-2005 year period, which is estimated on the basis of a shallow water wave hindcasting. The sea wind distributions are obtained through the application of the method by Yamaguchi et al.(2009) to the land-based measurement wind data acquired around the Inland Sea. Wave height intensity is dependent on the course and strength of a typhoon. In the outer area exposed to the Pacific Ocean, wave height generally decreases towards the bottom of the sea channel with the exception that it almost keeps incident height or it increases by blowing of strong winds in the area. In the semi-closed bay and inland area surrounded by the lands, the highest region of the wave height changes with the wind direction of persistent strong winds which depends on the course of a typhoon. This tendency can be clearly observed in the middle sea area of the Inland Sea.

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 The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR4) stated that "Warming of the climate system is unequivocal". In considering the countermeasures against the possible disasters, the global warming has to be taken into account. Not only a sea level rise, but also disastrous storm surges and destructive high waves accompanied by tremendous typhoons must be the urgent issues. In this study, on the basis of the experimental projection results simulated with the Atmospheric Global Climate Model (MRI-AGCM3.2) of the Innovative Program of Climate Change Projection for the 21th Century, we analyzed the climate data to clarify the changing trend of disaster scale around Kyushu district where the influence of the Global Warming might be found earlier than the other areas in Japan. As a result, it is clarified that the number of severe typhoon that approaches Japan will increase though the total number of typhoon that approaches Japan will decrease. Furthermore, it is found that the occurrence frequency of high waves tends to decrease though the maximum wave height will be higher.

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 The IPCC 4th Report indicates that the global mean sea level will increase and tropical cyclone may become more intense. The change in water level and waves due to the climate change is one of critical factors in the life extension plan of coastal defense facility. This paper, therefore, reviews the current design storm water level and offshore wave from a view of their return periods. Then, this paper summarizes the current scientific knowledge on the past and future change in mean sea level, storm surges, and waves, and then propose a method to give the future storm water level and offshore wave criteria for the performance evaluation of coastal defense facility at each year during the lifetime. These criteria are determined using the same concept as the current design but considers the climate change effects. Moreover, this paper discusses on a few technical issues, such as the design criteria for new or upgraded facility, the level 2 storm water level, and the continuity of wave and tide monitoring.

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 A coupled river discharge and ocean circulation model was developed, which aimed for the effective tool for the integrated environment management of the watershed area including rivers and ocean. The model consists of the distributed hydrological model, the unsteady flow model near river mouse, the ocean circulation model and the advective diffusion model. These four models are connected each other through the boundary conditions. We applied the model to the heavy rainfall case around Kiso-sansen rivers and Ise Bay during April 2003. It was concluded that the river water level calculation corresponded well to the observation, and the calculated suspended sediment distribution was qualitatively conincident with the MODIS satellite observation.

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 In numerical simulation of current and water quality in a sea under the influence of fresh water, problems related to reproducibility of the density distribution still remain. New observation stations has been set up in recent years and continues to measure and send out the vertical profiles of currents and such water quality as temperature, salinity and dissolved oxygen in some estuaries in Japan. In the present paper, four dimensional variational (4d-var) data assimilation is examined to improve the representation of the spatial distributions of salinity and water temperature, especially that of pycnocline in the innermost part of bay. The data which are observed at 10 stations in Osaka Bay every hour and includes 6 vertical profiles of salinity and temperature are used for the assimilation. The results show the great improvement of the representation of the profiles which do not contain the artificial distortions.

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 Tokyo bay is a typical enclosed bay which has a large population on the periphery, and accumulated sludge at the seabed consumes DO, which results in hypoxia in bottom layer during summer. Because of upwelling induced by wind, hypoxia comes up to sea water surface, which may kill fish and aquatic plants. Therefore, it is needed to understand the mechanism of the occurrence and transportation of hypoxia. Previous studies have shown that there is a problem in the reproducibility with forming stepped terrain by using the cartesian coordinate system. To solve such a problem, we applied Partial Cell into sinusoidal-shape topography in the three-dimensional numerical computation. Also, Partial Cell was applied into Tokyo Bay, which shows good agreement with field observation results in terms of vertical density profile.

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 CO₂ oceanic sequestration is considered to enable industry made CO₂ to be separated from the atmosphere. On the other hand, it is feared that the CO₂ injected in the coastal zone may lower pH of seawater, thus may adversely affect marine animals.
 For evaluating the biological influences, we have studied to predict the CO₂ distribution around the CO₂ injection site with the combination of near field model(gravitational plume model) with the far field model(ocean circulation model) developed by us.
 Based on the predicted CO₂ concentration, values of pH were computed. The minimum pH occurs at the injection point with 7.79. It was inferred that by reduction of pH occurs with the influence area of the injection point, considering the existing data of relation between pH values and the possibility of survival.

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 Short-period oscllation flow often emerges in Maizuru Bay where tidal current is week and estuarine circulation is strong. The oscillation flow which has the 1-hour to 2-hours periods is due to the secondary undulations of tide, and is storng at the baymouth. This study shows that the numerical simulation can reproduce the oscillation flow by setting short-period elevation at the open boundary. Then, numerical experiments show the spreading oceanic materials differs among with or without the oscillation flow at the baymouth.

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 Laboratory experiments on the leeway velocity of drifting objects have been conducted to investigate the drag coefficient ratio of 12 types of drifting body. The measured wave-induced drift velocities coincident well with the Stokes drift velocity. The drag coefficient ratio of drifting objects are found to be a function of the ratio of the projected frontal areas of the floating body above and under the water surface. The prection of the leeway trajectory of a drifting bouy on the sea of Japan is made under consideration of ocean current, tidal and drift currents. The prected trajectory of drifting bouy for 12 hours coincides well with the measured data.

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 Drifting garbage on the sea has a bad influence on economic activity and on coastal environment. Therefore, it is necessary to collect the garbage quickly and to understand the discharged source and the transport route are very important. On this study, the source and route of the garbage were analyzed by using the surface current data obtained by HF Radar and the collection records of garbage by garbage collection ship of the "Beikurin". The discharge date and location were estimated by using results of the convection and diffusion phenomena of 1,000 virtual trashes. Comparison with estimated results and the garbage collection records, reasonable results of discharged location and duration were obtained. From the results, it is suggested that surface current data by HF Radar has applicability to the garbage collection system.

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 The Load - Resistance Factor Design is now due in the design of an arctic structure. The specific load, which corresponds a certain return period, is used as the design load. The specific load would be calculated using the Monte Carlo simulation. The accuracy of calculated specific ice load depends on the deterministic equation to estimate ice force. Many equations to estimate ice force on a vertical structure have been proposed. However calculated ice forces have a wide variety. One of Molikpaq events in the Amauligak I-65 can give us well-documented full-scale data to evaluate those ice force equations. In this paper, the Molikpaq event on February 17^th, 1986 is chosen as a full-scale data. From ice conditions reported, probability density functions of ice conditions are established. The Monte Carlo simulations to obtain probability distributions of ice force are performed. Comparing the probability distributions with the Molikpaq data, each ice force equation is evaluated. 11 existing equations are evaluated, four of them could be either applicable to a large structure. Considering the equations to be applicable, it is concluded that a simple Korzavin type equation with the coefficient of 0.35 to 0.45 is recommendable.

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 Tests involving sea ice friction-related wear/abrasion on various metals such as carbon steel, stainless steel and titanium were carried out to clarify the characteristics of deterioration in steel structures such as sheet piles in ice covered areas. Each metal test piece was placed in contact with artificial saline ice under certain levels of pressure using an oil jack, and reciprocating motion was introduced. Although wear also increased with higher levels of contact pressure, the rate of increase fell at pressure values of around 0.5 MPa or more. Conversely, the wear amounts of stainless steel and titanium were close to zero, despite the minimal difference between the Brinell hardness values of the metals. Accordingly, the main factor influencing this type of deterioration in carbon steel is corrosive wear rather than adhesive wear. Further, because the wear rate per unit time for carbon steel increased linearly with the sliding speed, it can be concluded that ice action promote the corrosion of steel by stimulating its surface.

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 We had conducted medium scale field indentation tests of JOIA projects, and have reported the pattern of local pressure distribution by the use of pressure data of Tactile sensor (Takeuchi, et. al., 2004). There are high pressure zones mainly inside line-like contact zone at the interface between icesheet and structure in the brittle condition, and these are forming and fading rapidly with a certain size and pressure. It is very interesting to investigate the characteristics of high pressure zone, since force of high pressure zone plays an important role on global force and it relates to non-simultaneous stress transmission to structure in the brittle condition. Mechanism of high pressure zone has been reported by Jordaan (2001, 2008) and Dempsey et al. (2001) have treated the estimation of its pressure theoretically. In the paper, "labeling process" of the image processing was newly applied to tactile sensor data, and the process allows us to find a zone that has adjacent grid pressures. Area, pressure and location of high pressure zone were estimated at each frame of Tactile sensor data through threshold which was taken as a uni-axial compressive strength here.
 In the paper, area and force of each zone were calculated and they have a linear relation. Acting position, of x- and y- direction calculated from moment and force of each zone, and distance, between adjacent acting positions, were estimated. Statistics on area, force, acting position and distance of each high pressure zone were considered. Especially, the probability density function on area and distance looks like log-normal type. In addition, these findings allow us to conduct Monte Carlo Simulation to evaluate the slope of upper limit of pressure area curve.

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 Topographic change of an artificial shallow is investigated experimentally in terms of bottom flow velocity on the surface of the shallow and pore-water pressure on the surface layer of the shallow. Experimental results show that the erosion occurs from the upper part of the slope to the offshore part of the crown, which corresponds to a breaking point judged from the spatial distributions of the wave height and the mean water level. It is also found that the area of the topographic change increases with an incident wave height and an incident wave period. For the shallow composed of fine sediments, a relative vertical effective stress ratio (RVESR) reduces during onshore bottom flow velocity while the RVESR rises during offshore bottom flow velocity, and suggest that offshore sediment transport can be accelerated because it is inferred that restricting force between sediment particles decreases with the increase in the RVESR. Furthermore, it is demonstrated that sediment transport of the shallow can be evaluated reasonably well using a Shields parameter modified to take into account pore-water pressure on the surface layer of the shallow, and consequently it is essential to consider the pore-water pressure when assessing sediment transport and resulting topographic change of the shallow.

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 With past development in littoral region through land reclamation and port improvement etc., a lot of natural tideland have been disappeared, opportunity to have contact with the natural sea has been decreased and habitat, egg-laying site and growing land for a huge variety of life have also been decreased. Because of these points, recovery of mudflats and see grass bed is gathering momentum, but there are the depletion of natural materials and the shortage of chemical knowledge on recovery of artificial tideland.
 In this study, two years verification test applying granulated fly ash to materials of artificial tideland at the actual sea was conducted mainly to examine applicability of granulated fly ash to growing bed for clams.

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 The method of uplifting the ground surface by pressure injection of slurry sludge enabled to restore the settled ground without influencing the creatures living on and inside the tidal flat. In order to establish the method,this study was carried out to examine the effectiveness of several auxiliary methods to uplift the ground smoothly. As a result of experiment, it turns out that softening of original grond in the horizontal plane is most effective for the purpose. Especially, soft layer is successfully formed by improving the arrangement of injection nozzles in a water-jet cutting method. A practical construction sequence, which is composed of water-jet cutting and pressure injection of slurry clay, is proposed in this study.

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 An artificial tidal flat has been reclaimed with dredged marine clay in Port of Tokuyamakudamatsu. The artificial tidal flat was soft clay ground, so that reclamation and sand capping works were difficulty. Then, the ground will have consolidated for a long time after the construction. Therefore, we have been investigating into grounds of the artificial tidal flat from immediately after the construction at 2009. This research paper reports the reclaiming and sand capping cases and results of the field examination on the artificial tidal flat grounds and the consolidation analysis.

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 In this study, a new construction method, in which, a pressure injection of dredged slurry is carried out in the reclaimed clay layer under the capping layer, is developed. A 1/25 scale laboratory model test was used, where the pressure injection test of soft clay was made under the various conditions. Laboratory model experiments showed that the pressure injection method has a possibility to be used in the actual tidal flat project by making two improvements on the injection methods; one is to give mechanical distirbances to the in-situ clay layer horizontally ant the other is installation of the pressing plate on the injection hole. There was a liner relationship between the volume of injected clay slurry and the area of influence.

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 Seasonal quantitative sampling was conducted to compare benthic assemblage (mollusks and crabs) between a created and a natural tidal flat after ca. 5 years of creation. The number of individuals and species were lower in the created habitat and the dominant species composition completely differed between the two habitats. In particular, a mud snail Batillaria cumingi that was overwhelmingly dominant species in the natural habitat was almost not observed in the created habitat. Judging from the benthic assemblage, therefore, the created habitat was not enough to compensate for the losing natural habitat. Continuous survey was needed for a better ecological understanding of the artificially created tidal flat.

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 Local submarine groudwater flow directing from the shore to the ocean for exfiltrating near the shoreline is known to be formed under sandy beach due to surface waves. Although the grounwater flow is one of the important factors to bring various substances (e.g. nutrients and oxygen) into the coastal water as an outlet phase of the transportation process from the land to the ocean, only a little is known because of the limitation of the measurement techniques for this kind of flow. We propose a technique to estimate transport and diffusion velocities by fitting a solution of the one-dimensional transport-diffusion equation to the experimental data obtained by measuring the evolution of the NaCl concentration under the sandy bed. The relationship between the wave conditions and transport-diffusion velocities of NaCl solution in the seepage flow is characterized through the present experiments.

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 Some of the natural beaches in the Seto Inland Sea are expected to have a key role as shore protection facility. However, temporal - spatial variation of topography change and sediment property on the beach surface and trapping effect of blown sand by vegetation are still not well understood. In this study, field observations in the Narugashima Island in the vicinity of AWAJI Island in Japan and the laboratory experiments were carried out. In the field observation, we confirmed the vegetation growing in the vicinity of back beach affects on the sediment transport and the local topography change. On the other hand, in the laboratory experiments, it is clarified that the greater density of vegetation has a beneficial effect on trapping the blown sand. This is a similar trend observed in field observations.

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 On the newly developed concrete block mixed with waste scallop shells as aggregates (SC-block), material characteristic tests, field demonstrations, field research of seaweed growth were carried out. In an estimation in the case of seaweed bed formation by 2,000 blocks, cost increased by 4 % but CO₂ was hardly discharged when SC-blocks were used instead of normal concrete blocks.

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 In the inner part of Osaka Bay, eutrophication has resulted in deterioration in quality of water and bottom sediments, while in western part of the bay, oligotrophication has resulted in serious damage to laver culture such as bleaching of "nori". A pilot project is underway in Hyogo Prefecture which seeks to adjust nutrient imbalance through cultivating sea bottom. We carried out field survey of water quality in the pilot project area. According to the results, "cultivation of sea bottom" is an effective method to adjust seawater nutrient imbalance.

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 The heavy rain disaster occurred in Amami Oshima in October, 2010. A large amount of sediment was supplied from land to coastal area during this disaster, and it would have a great influence on the mangrove and coral ecosystem.
 In this study, field observations of mangrove area and coral reef were conducted to reveal the effect of the heavy rain disaster on mangrove and coral ecosystem. The deposited sediment on the coastal area drastically reduce the cover degree of coral. The mangrove trees only along the main channel were flushed due to the bank erosion, but the rapid deposition of the land derived sediment didn't occur in the mangrove forest.

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 Kagoshima Bay, which is located in the southern partof Kyushu Island in Japan,is composed of an innermostbasin (Aira caldera), and central basin(Ata caldera) and bay mouth. The bay mouth and central basinareconnected by a shallow channel(about 100m depth), while innermostbasinis connected to the central one by only anarrow channel, called the "Nishi Sakurajima Suido" (West Sakurajima Waterway). We are concerned about the water quality within the bay, and how phosphorous and nitrogen from households, aquaculture farms, agricultural runoff and rivers may contribute to eutrophication in the bay. Furthermore, the DO level in the inner basin has also decreased in recent years. In this research we examined sulfide content, organic matter content and particle size compositionusing submarine superficial deposit samples extracted from sampling stations throughout Kagoshima bay, which are some of the chemical indices of bottom sediments, and classified the sediment types.

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 This study aims at investigating relationships between distributions of corals and physical environments in Amitori Bay, Iriomote Island, Japan. Field observations in Amitori Bay were performed to obtain the data of the distributions of corals, water temperature, inflow rate from rivers, wind speeds and so on. Moreover, an ocean current model CCM and a wave model were used to analyze the spatial and temporal distributions of the fine-grained sediments and the wave heights.
 It was shown that the forms and sizes of the corals are largely different depending on the locations in Amitori Bay. This is because the locations respectively have different physical environments. Furthermore, the results of the numerical analyses showed that the distributions of the corals are greatly influenced by the effects of the high waves and the fine-grained sediment transport.

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 Quality of water and sediments (Eh, organic matter and hydrogen sulfide) were investigated every week in order to clarify the short-term variations in the inner western area of Ariake Bay. The physical replenishment (stratification) due to the freshwater input and high density water intrusion casused hypoxia, and meteorological effects, vertical mixing due to the wind including the typhoon, was made hypoxia vanish. Hydrogen sulfide of high concentration was generated in the situation of development of hypoxia, and the concentration was decreased due to the wind specially. The area of low Eh (-180mV) corresponded with that of high concentration of hydrogen sulfide. The increase of mortality of ark clam (Scapharca subcrenata) toward the end of July was caused by hypoxia and generation of hydrogen sulfide under low pH (about 7.2) in the sediments due to the decomposition of organic matter.

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 A prototype model experiment, covering the seabed with fly ash beans, has been in progress since June 2010 at the bottom of Kaita Bay, located in the innermost region of the larger Hiroshima Bay in Japan. In order to verify the effectiveness of sediment improvement, the site has been monitored over the approximately one and a half years since the experiment began, primarily in summer and winter. The experiment was conducted with three zones demarcated, covered with thicknesses of 5cm, 10cm and 20cm respectively, which were then assessed in comparison to one another and to the surrounding area. The assessment determined that covering the seabed with fly ash beans contributes positively in terms of trapping of suspended mud, improvement of sediment quality, and creation of an environment favorable to marine organisms, and that these improvements were being sustained.
 However, the possibility of suspended mud accumulating in the covering layer and completely blocking its gaps, thereby detracting from the improvement of sediment quality, was also considered. In fact, it was found that in the zone with coating 5cm in thickness, the degree of improvement had declined considerably since the experiment began. In addition to clarifying the degree of sediment improvement through covering the seabed with fly ash beans, this experiment is intended to evaluate the sustainability of this improvement. Henceforth, the scale of the operation area will be expanded, and the relevant findings organized appropriately.

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 In this research, the design method in order to apply mud improvement effect by granulated coal ash (GCA) to the field is proposed. Organic matter content of mud in Fukuyama cove is more than 20%, and water content of surface mud is more than 1000%. In addition, scum floating on the water emanate bad smell, special phenomenon not found in other seas occurs in Fukuyama cove. It is confirmed that scum has many organic matters with fatty acid and its density is smaller than ordinary mud of sea bottom. And it is estimated from field observation that the generation area of scum is around the mouth of the cannel. Sinking thickness in scattering with GCA depends on not only water content but also rheological characteristics on mud. From this result the method from liquid and plastic limit test to estimate the sinking thickness is proposed.

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 The Collage of Land, Infrastructure, Transport and Tourism has carried out field trip to Kujukuri Beach every year to comprehensively learn real phenomena occurring not only on the beach but also in the hinterland and enhance the ability of each engineer on coastal engineering. In this paper, such experience in which 20 students participated was reported. The importance of learning through the field trip to coasts was discussed.

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 The Kyushu Regional Development Bureau of Japans Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has progressed shore protection facilities construction project at 4 sites of Beppukou Coast which consists of Shoningahama, Mochigahama, Kitahama-1, and Kitahama-2 in Beppu city, Oita. The project intends to create Sato-hama, the coastal zone which the residents can be proud of. Kitahama-1 area is the target site of this study and has had problems on aging of existing structures and insufficient protection capacity. The development plan of the coastal protection has been examined by government-private sectors cooperation since 2010, catering to coastal environment and use as well as coastal protection, aiming at the start of construction in 2012.
 The development plan has decided through public involvement and "double parapet shore protection" is adapted as the type of protection structure, in which two parallel parapets on the top of seawall and a permeable layer between the two parapets are arranged. The development plan also includes an arrangement of anti-spray zone behind the backward parapet of setback line for coastal use and scenery. As technical investigation of the structure, the height of parapet and the width of permeable layer are important factors for preventing from wave overtopping, and the optimum combination of them has been examined through physical and numerical models.

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 It is important for Japan, which is one of the largest car production/export country, to grasp the trend of the transportation of finished vehicles in the world. However, there are few information concerning the pure car carrier which transports finished vehicles. Based on this background, this paper analyzed the trend of transportation of finished vehicles and the size of pure car carrier. By this analysis, this paper aimed to contribute the policy decision for marine transportation of finished vehicles.
 About the trend of transportation of finished vehicles, the relation between vehicle capacity of pure car carrier and car production / volume of sales and the state of transshipped vehicles were analyzed. And, the analysis concerning the size of pure car carrier was done focused on operator and service area.

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 Volume of world container cargo has been increasing rapidly and competition among container ports has been intensifying. Each container terminal aims to improve occupancy rate to survive against this competition. Also in Japan, the international container strategic port policy is progressing.
 In this background, this study developed the procedure to make berth window by using AIS data and analyzed berth occupancy rate of world container terminals.

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 Due to the rapid economic growth in Asian countries, the amount of container cargo has been increasing in recent years and the environment related to carriage of maritime container transport has been changing such as introduction of large container vessels and new container ship services. Based on these back grounds, in order to support more effective and efficient port developments in Japan, we have developed the model on international maritime container cargo flow by sacrifice model. And we have examined the time value distribution of maritime container cargo and the routes of container cargo transportation by considering the new data, and so on.

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 This research presents a navigation simulation system aimed for safe navigation in the coastal water area. Most of the coastal stranding is attributed to shallow waters. In this paper, we propose an effective method to communicate information regarding water depth, the atmosphere, and the oceans using GIS to prevent ship stranding. With this navigation simulation, it is possible to understand and visually experience the actual situation of sailing circumstance in the navigation area. Expected results are 1) increased technological knowledge into design and presentation of 3-dimensional map, 2) illustrated Osaka Bay and related information with regard to the water and voyage. We also expect to use GIS in more wide range such as combining it with receiving apparatus such as Automatic Information System, Global Positioning System, and etc.

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 The information on navigation is very important for safe navigation. The safety of a sailing ship is demanded for the prevention of a marine disaster. The causes of a marine disaster are collision, stranding of a ship and so on. Especially, the most of marine disaster causes in the shallow water relatively of the coastal area. It is very important to propose the effective information of navigation for the prevention of a marine disaster. Also, the information of navigation which supports the safety of a sailing ship is demanded. The present paper proposes the effective presentation for information of navigation using GIS and the efficiency of a car navigation used by the road traffic is examined for prevention of a marine disaster.

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