This study investigates experimentally wave-current interaction and proposes a numerical model to simulate hydrodynamics in wave-current coexisting fields. The experimental results show that the wave height increases initially, and then decreases gradually with the wave propagations. Decrease of wave celerity causes deformations of wave crest lines, which results in the convergence of waves near the river mouth. Furthermore, the current velocity decreases with continuous wave-current interactions. The wave period, the intensity of currents, and the angle of the incident wave are confirmed to be key parameters to govern the wave-current interaction. The proposed numerical model is found to reproduce well the experimental results.

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A 26-year wave hindcasting for which a backward ray tracing model is applied is conducted station by station along the West Coast of Suruga Bay connecting to the Pacific Ocean. Hourly wind distribution is provided with the ECMWF analysis/reanalysis surface winds-based data set in the open ocean and with the measured winds-based data set in the nearshore area respectively. Comparison between the hindcasts and the measurements at 6 stations reveals that the model reproduces the wave climatic conditions well, including azimuthal distribution of mean wave direction at each station along the Coast, that it makes discernible a small difference between the wave conditions at the neighboring two stations, and that it explains the occurrence rate of multi-peaked spectra reasonably. Also, the wave computations at nearshore and offshore points suggest a great contribution to a significant change of propagating wave directions associated with wave refraction due to a shoal.

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Accurate sea-wind data are indispensable for improvement of accuracy of wave hindcasting. However, it is very difficult to obtain accurate sea-wind data around inner bay area for a long term even today. In this paper, we suggest a practical method for estimating accurate sea-winds in inner bay area easily without spending heavy calculation load, i. e., a simple method by using available weather chart data set together with data calculated with meso-scale meteorological model (MM5). For the purpose of examining its applicability and accuracy, we applied it to Osaka bay. The results show the improvement of wave hindcasting accuracy by using the proposed method.

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An objective analysis, the optimum interpolation method, was applied for estimating directional wave spectrum from the data of a high resolution wave simulation system and the NOWPHAS coastal wave observation system. In the analysis, the number of components of directional spectrum with respect to frequency and direction was appropriately determined to minimize the error of the initial guess of the directional spectrum since it is strongly required to take into account the balance between the accuracy of the observation data and that of the numerical simulation data in the assimilation. The proposed method enabled the accuracy improvement of estimating directional wave spectrum as well as the significant wave height and period.

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Properties of the current velocity index of the Osumi Branch Current (OBC) in the Osumi Strait south of Kyushu were re-examined using sea-level data during 1971-2003. The high correlation with the current velocity measured in the Osumi Strait confirmed that the sea-level difference between Nishino-omote and Odomari is a good index to monitor the current velocity of the OBC. Using daily values of the index and water temperature measured in Kagoshima Bay in 1999, it is found that the current velocity fluctuations of the OBC with periods less than about 8 days significantly contribute to oceanic water inflow into Kagoshima Bay. Moreover, the oceanic water is shown to reach to the central part of Kagoshima Bay about 1.3 day after it enters into the bay along the Osumi Peninsula.

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Yatsushiro Sea is an enclosed water area, where the wave height is low and the tidal current is also quiet. Therefore, the seawater exchange with the open sea is not good. Furthermore, the driftage is running from Kumagawa River, and it drifts with the current of Yatushiro Sea. In this study, a drifting small buoy system equipped with a GPS receiver is used for the purpose of observing a tide of Yatsushiro Sea. The effect of current on the buoy was investigated experimentally and numerically, and it was developed the optimum shape of buoy.

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The tidal and sea current turbines are one of potential sources for utilization of natural energies. When applying them to the actual sea, it is necessary to evaluate how much increase of hydro forces acting on the turbines, and to examine if any drop or increase of electrical generation due to waves. Therefore, we conducted 2-dimensional tank tests in the current, both wave and current to measure the loads, rotational speed and output volts induced in the 1/100 scale turbine. As simple stream tube theory often apply to analyze a turbine in uniform flow, so we use it for the analyses of hydro forces and energy outputs of the turbine in coexistence of wave and current. The paper presented the comparison the model tests results with the theoretical calculation to clarify the effects of waves to the turbine.

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A set of unified formulas for prediction of wave overtopping rate at coastal structures have been derived by analyzing the CLASH database. The new formulas are applicable for vertical seawalls, smooth impermeable slopes, and composite seawalls with frontal mounds built with Tetrapods. The formulas are simple but cover the full range of water depth from the shoreline to deep water. The effects of the toe depth and the seabed slope on wave overtopping rate are duly incorporated in the formulas. Prediction performance of the new formulas is better than the EurOtop formula for both vertical walls and inclined seawalls.

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The purpose of this study is to investigate wave deformation on a reef and wave overtopping characteristics around a vertical seawall by carrying out hydraulic model experiments and numerical computations with a two-dimensional numerical wave flume based on a VOF method “CADMAS-SURF”. The validity and utility of the CADMAS-SURF are, furthermore, verified by comparing with the experimental results.
The comparison of the computational and experimental results reveals that the CADMAS-SURF can reproduce well the experimental results, such as the spatial and temporal variation of free water surface on the reef and wave overtopping rate of the seawall. The results also show that the mean water level increases due to successive wave breaking on the reef and wave set-up remarkably takes place in front of the seawall. The full consideration of the influence of wave deformation is, therefore, found to be important in designing coastal revetments.

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Overtopping rate of waves over a seawall on coral reef flat is experimentally studied. Through comparisons of overtopping phenomena for seawalls built on a uniformly slopping bottom and on a coral reef flat, it is shown that the wave overtopping for a reef coast is strongly influenced by sea surface raise of surf beat. It is then shown that Goda's design diagrams of wave overtopping rate is not refered for seawall on reef flat.
A new method for the usage of Goda's diagrams for seawall on reef flat is proposed. In the method, not only the wave set-up but the sea water level raise of surf beat on the reef flat is taken to account into the design sea level. It is verified by the comparisons with experimental data.

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Two-dimensional hydraulic model tests and numerical calculations were conducted to reveal the stability of concrete bridge on reef against storm waves. The characteristics of standing wave were examined for different reef conditions by the numerical calculation with CADMAS-SURF. Based on the numerical test results, the patterns of wave run-up were disclosed for several reef conditions.
The bridge girder failure at Ohmori Coast, Kamoenai, Hokkaido in 2004 was predominant at the loop of standing wave condition, and the same damage pattern was confirmed by the wave force tests. The characteristics of horizontal wave force on bridge pier were also studied to be critical at the node of the standing wave.

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A new device has been developed for measuring wave pressure at the field level. It is configured with a pressure and 3 directional acceleration sensors as well as a self-recording system with 32 MB memory. It can work for 45 days with a cell battery under 20Hz sampling frequency and costs less than one tenth of the existing cable type pressure measuring systems. Performance of the device has been tested on an upright section of a breakwater on coral reef flat in Okinawa of Japan. Data obtained shows that the new device may treat as reliable.
The pressure acting on a breakwater on the reef flat is strongly influenced by the water surface level rise of surf beat waves. Pressure distribution shows that pressure due to a short period wave can be estimated by the partially reflected wave theory, so that the resultant depth of still water level, wave set-up and surface level rise due to surf beat wave can be regarded as the design water depth.

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In harbors and fishing ports, a mooring ship might agitate though the surface of the seawater is calm. The agitation of a mooring ship causes damage of hull, cutting of mooring rope, cargo handling difficulty, and these become problems. In order to grasp agitation, observation of agitation is performed. If the case where the limit of agitation must be defined politically when minute agitation is a problem is assumed, it is necessary to establish the highly precise observation technique.
As one of the methods, there is observation of agitation using GPS. This method analyzes three dimensional of agitation of a mooring ship by measuring the coordinates of three points on the hull by GPS. We executed the GPS observation and the video observation at the same time, and compared the results and evaluated the observation method. As a result, the utility of the GPS observation was confirmed.

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For floating structures in deep sea, tout mooring is used rather than conventional catenary mooring, together with high holding anchors such as a plate like vertical loaded anchor or a suction pile and so on. While these anchors are deeply installed under sea bed, friction or adhesion and earth pressure act on a ground line laid under the sea bed. As a result, the attitude and tension induced in the buried ground line may be influenced. It becomes more important in mooring design, deeper an anchor is installed. So, we proposed a mooring design method for the line from an anchor undergrounded in clay or sand stratum to a floating unit. The paper describes the effects of soil strength, submerged weight of the line and mooring positions on the shape and tension distribution of the line quantitatively.

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For a type of “perfectly underwater”structures moored by some tension legs, namely submerged floating structures, the dynamic behaviors of the floating body are expected to involve many severe design and computational problems. In addition, three dimensional motions with six degrees of freedom induced by some external forces like strong waves and earthquakes may be very complex and it is difficult to explain the mechanisms of the behavior accurately.
This paper presents the three dimensional dynamic response characteristics of the submerged floating structures. Three dimensional restoring forces due to tension legs are introduced and dynamic properties such as natural period and fluctuating tension force are investigated here. Especially, we focus on the effect of tension leg arrangement on dynamic characteristics of submerged floating structure.

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It is necessary to study on the safety of “the refugee of harbour” from the viewpoint of port planning, too. Recently, breakage casualties of stranded ships become very serious in the port operation and the coastal environment. However, these problems have not been discussed among the coastal engineering and shipbuilding, neither. In this study, we summarize the importance of this point by showing the statistic of casualties. Then, the strength of ship hulls is calculated with strip method and the basic dynamics of material, when ships are designed to navigate in the ocean. Since the calculated results cannot explain the breakage casualties, the possibility of the enlarged stress due to the crack is also considered as a simple example. The results can explain that the breakage of stranded ships may be caused by the enlarged stress due to cracks on the ship hull. Therefore, the safety of coastal areas outside harbour should be considered totally with anchored ship motions and fracture mechanics of ships in detail in the future.

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This paper discusses the wharf operation ratio in a port by use of wave data obtained by Nationwide Wave information network for Ports and HAabourS (NOWPHAS). The observed interval of wave data was twenty minuets of every two hours due to the limitation of data transformation during about thirty years after starting the wave observation in 1970. In recent years, continuous wave data have been observed in the remarkable progress of information processing and communication technology. However, the effect on the wharf operation ratio depending on the difference of wave observation interval was not discussed. This paper thus examines the differences of wharf operation ratio estimated when discontinuous or continuous data were applied, respectively.

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It is extremely important to estimate damage when tsunami disaster for vessels in order to prevent or reduce damage of vessels. Overthrow of vessels and grounding on a wharf concern on when vessels are moored in harbors. This paper reproduces behaviors of vessels moored near wharfs due to tsunamis by using the moving particle semiimplicit method (MPS). The two dimensional MPS method program code has been developed and the validity of the program is proven by comparing with model test.
Solitary waves have been applied to simulated tsunamis and the model experiments. A box like model is used to a floating structure in numerical simulations using the two dimensional MPS method. The present numerical results are compared with the experimental results and the applicability of the MPS method is discussed. In addition, the mooring force was considered. The behavior of grounding on a wharf of moored vessel is examined. As a result, the usefulness of this numerical technique is confirmed.

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In recent years, CFD (Computational Fluid Dynamics) has been actively employed in order to predict complicated hydraulic phenomena and solve practical problems in coastal engineering, in accordance with the developments of computer performance and high-order numerical schemes. The purpose of this study is to efficiently compute wave deformation and wave overtopping around a revetment on a reef in Okinawa Main Island making use of two different numerical models, namely a depth-averaged numerical model based on a Boussinesq equation “NOWT-PARI” and a vertical two-dimensional numerical wave flume based on a VOF method “CADMAS-SURF”.
The numerical results show that NOWT-PARI is capable of simulating wave deformations including wave reflection, refraction and diffraction appropriately. The CADMAS-SURF is confirmed to be able to compute wave overtopping phenomena around the revetment more precisely by setting proper incident wave conditions and bottom topography based on the numerical results by “NOWT-PARI” with due consideration of wave direction.

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The consideration of transmitted waves by overtopping on coastal breakwaters as well as progressive waves from harbor entrances is of importance to examine in detail and estimate harbor tranquility at high waves. However, the conventional models of wave transformations, such as energy balance equation, wave ray method and so on, cannot compute the influence of the transmitted waves appropriately. The present study is, therefore, aimed at discussing the applicability of a two-dimensional numerical wave flume “CADMAS-SURF” based on the VOF method for transmitted wave phenomena behind an upright breakwater by comparing with hydraulic model experiments under regular and irregular wave actions. As a result, the CADMAS-SURF is found to be capable of reproducing well the experimental results regarding the wave height and frequency spectra of the transmitted waves.

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A stepped seawall with drainage is one of the coastal structures for reducing wave overtopping. The accurate prediction of wave overtopping is of importance in order to design the seawall economically. However, the previous design diagrams for the estimation of wave overtopping rate cannot be used for the complex shape of a seawall.
The main purpose of this paper is to investigate irregular wave overtopping process on a stepped seawall with drainage and verify the utility of a two-dimensional numerical wave flume “CADMAS-SURF” by implementing hydraulic experiments and numerical simulations. The comparison of the numerical and experimental results reveals that the CADMAS-SURF can appropriately reproduce wave overtopping phenomena under irregular wave actions.

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A numerical model for computing the deformations of rubble mound, composed of various size materials, was proposed. In the numerical model, wave field into the mound structure was computed by CADMAS-SURF. And the deformation of the structure was computed using DEM. Interaction of wave and sectional deformation of structures was considered, and to present the variation of behavior caused by various properties, computation was carried out with random coefficients by Monte Carlo simulation for contact stiffness and friction angle. The validity of the model was investigated by comparing with laboratory tests. The experiments were carried out using rubbles and glass balls with the diameters of 2.9cm, 2.6cm and 1.5cm. Furthermore, the deformation characteristics of rubble mound composed of various size materials were clarified. The applicability of the model was discussed by comparing with the experimental results.

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Estimation of wave force action on coastal structure is very important engineering problem. CADMAS-SURF is one of the effective calculation methods for wave force on the coastal structure. However, some problems are pointed out to the numerical modeling of sloping breakwater by CADMAS-SURF. For example, it is difficult to determine the reasonable drag coefficient, and grid dependency of resistance is remarkable.
The purpose of this study is the definition of the practical resistance calculation method for wave force acting on superstructure of sloping breakwater. First, we clarified grid dependency of resistance using conventional resistance calculation method and examined influence of value of drag coefficient. Next, Dupuit-Forhhimer method is introduced on resistance calculation, comparison between experimental result and calculation result is conducted. As a result, we confirmed that practical calculation result was obtained.

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Ice booms were installed at the entrance of Lake Saloma to prevent sea ice moving into the lake, which had caused serious damage to aquaculture facilities. We performed the model experiments on interaction between sea ice floes and an ice control facility such as the ice boom in order to develop an appropriate design method. Loads acting on ice booms did not depend greatly on the shapes of ice floes and the conditions of side walls (flat or not) of the water channel, considering variations of the loads under the same test condition. Also, we developed an analytical solution for the transmitting ice force into downstream, which was taken the influence or restriction by side walls or ice floes themselves into consideration. We confirmed that the solution could represent tendencies of the experimental results.

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The strength of natural sea ice has a lot of scatter due to variations in its growing process. For engineering purposes, it is necessary to understand this strength randomness. The uniaxial compressive strength of natural sea ice at Lake Saroma was analyzed statistically to find an appropriate probability density function that would fit the strength data. Furthermore, peaks occurring in subsequent ice load data obtained in medium scale field indentation tests carried out by the JOIA project were analyzed statistically, since it had been found that each peak load was due to flaking failure of ice in an independent ice failure zone. From a Chi square test for goodness of fit, it was found that both uniaxial compressive strength and peak load fit a log-normal density function with 3 parameters. From this, a method for generating strength and peaks of ice load based on ice failure in the brittle condition can be developed.

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Structural pipe-in-pipe cross-sections have significant potential for application in offshore oil and gas production systems because of their property that combines thermal insulation performance with structural strength and self weight in an integrated way. Such cross-sections comprise inner and outer thin walled pipes with the annulus between them fully filled by a selectable filler material to impart an appropriate combination of properties. For offshore pipelines, bending characteristics become one of the most important factors for the structural design of the pipelines. The purpose of this research is to investigate the bending characteristics of such pipe-in-pipe systems analytically by considering the Brazier effect. Results are presented to show the variation of the degree of ovalization and bending moment with the relative elastic modulus of the filler and pipe materials and the filler thickness.

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A suction oil skimming system using water-driven eductor was developed. This system can be driven by nothing but high-pressure water of 0.5 to 0.6 MPa in pressure and is a good option to add oil recovery function to debris sweeping vessels without oil recovery function so far. Usually debris sweeping vessels has water cannons for manipulating floating debris whose motive water is also used for driving the new oil skimming system. The development started with basic suction performance tests on water-driven eductor followed by system design and oil recovery performance tests in a real scale simulation tank, and finally proved the system has good oil recovery performance in various conditions encountered in real sea.
The system has been adopted as an oil recovery system for a real vessel Ondo-2000 which owned and operated by Chugoku regional bureau of MLIT this spring.

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The present paper shows field simulation of the Spilled Oil Tracking Buoy (SOTAB) system. The system is developed to track spilled oil and to report position, wind direction and velocity, and current data in real time from the sea via radio waves. These data will be used for predicting oil drift destination. We carried out the field simulation test at Uchiura Bay in Numazu, Japan. We made mission that SOTAB detects floating false target as oil slick, calculates the target position, and moves toward it. We found that SOTAB can surely take the data of position, wind direction and velocity in real time. However, SOTAB needs downsizing of its body in order to treat it easily on the sea. We propose SOTAB as one of the supportive system for large-scale oil spill response concerned. It will help to know accurate oil slick positioning in real time.

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In West Channel around the Honjo area of Lake Nakaumi, the monitoring of dike removal and the estimation of turbidity distribution using satellite “Daichi” (ALOS) AVNIR-2 sensor data was tested. Turbidity was estimated by a simple statistical model using satellite/in-situ data set. The AVNIR-2 data used is four scenes from August, 2006 to September, 2007. As a result, the following matters were clarified. The condition of dike removal in West Channel of Honjo area was monitored from the satellite image clearly. A statistically significant correlation (r=0.79 and r=0.88) was observed between reflectance of AVNIR-2 Band 4 (760-890nm) and surface turbidity.

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Numerical simulation of the behavior of oceanic properties is necessary for management of coastal environments. A numerical model is developed to forecast flow pattern and suspended solid (SS) distribution around Mizusmma Port. Observations of flow fields and SS characteristics were undertaken in a previous study during low-temperature, rainy, and high-temperature seasons. This paper shows that the model simulates the observed flow pattern and SS distribution around Mizushima Port with high accuracy in the three seasons.

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Re-suspension and settling parameters for suspended sediments (SS) were estimated using current data and acoustic backscatter obtained with an Acoustic Doppler Current Profiler (ADCP) over three seasons (cold season, rainy season, and hot season) in 2006. SS concentrations were also obtained by filtering seawater in each season. Results indicated settling velocities of around 20m/d, and critical bottom shear stress of erosion of between 0.1N/mm2 and 0.5N/mm2. The critical bottom shear stress varied with season, being lower in the hot than in the cold season.

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Suspended sediment concentration and current velocity were measured continuously by Acoustic Doppler Current Profiler at the inner part of the Ariake Sound. Simultaneously, shear strength of the surface of the bottom mud was measured around the mooring point. Shear strength which measured by viscosity meter had finer relationships between vane shear strength. Multiple regression analysis was applied to the maximum SS concentration in every 15 hours. The main factor of the variation of the SS was the bottom shear stress. Sub-factor of the variation of SS concentration were wind velocity and the shear strength of the surface bottom mud.

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When dredging in rivers, lakes and canals, control on diffusion of suspended sediment contaminated by toxic substances such as dioxin and PCB has become a matter of utmost concern in recent years. Particularly for shallow and narrow waters, development of a new grab dredging system which minimizes turbidity and affect on the ecosystem has been longed for.
In this research, the degree of turbidity and characteristic of suspended sediment diffusion generated by the new Spill Controlled Bucket (SCB) Dredging System and by the conventional method using excavator had been monitored and compared in Lake Biwa. As a result, the degree of turbidity generated by the SCB had reached only 27.1% of that of the conventional method. Furthermore, numerical simulation of the turbidity showed a good match with the actual measurement and suggested that the forecast of diffusion process would be practical.

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Dams are constructed on many rivers to generate hydroelectric power and store water etc. However large amounts of sand accumulate on the upstream sides of these dams, negatively affecting their functions. Therefore, excluding this sediment is a problem. But the way that carrying this sediment downstream impacts the benthos has not been studied. Therefore, I undertook this study to investigate the influence of a mass outflow of sediment on the benthos of an estuary. The results suggest that this inflow of sediment influences the production of the phytoplankton and also has a good impact on the benthos; increasing its biodiversity for example.

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This paper presents the methods of the development of fishing ports for the supplying safe seafood products, based on the some rules on the food hygiene control and on the eco-label system which is useful for fishery resource management in Japan. First, we analyze the issue of the hygiene control for the fresh fish on the distribution process from the landing places to the consumers and propose the method to estimate the hygiene level with the two factors; the water quality, control and the sanitary condition of the working areas at the fishing ports, landing places and the auction halls on the distribution process, etc. Secondly, we propose the method to select whether fishery products are contribute to be sustainable or not, as secure the validity of the sea food hygiene control at the fishing ports.

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The CO₂ emissions from the activities in fishing village are caused by the consumption of fossil fuels and waste emissions. The reduction of CO₂ emissions will be possible by saving energy, innovation of new energy and new technology and effective use of waste emissions.
Sampling Minamikayabe area in Hakodate City, We present the following scenarios that reduce CO₂ emissions by fishery infrastructures and calculate the amount of CO₂ reductions due to the above scenarios. In the end, the effects of this reductions are evaluated using the WIO (waste input-output table).

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The main aims of the projects on the development of fisheries infrastructures were formerly improvement of working conditions at landing places. Recently, those projects make a contribution to the structural reform on distribution system of fishing products and make it clear that those projects bring good result, such as stability of the market prices of fishing products. We, first, review those projects' plan. Secondly, as a case study, we introduce those projects' effects which are improvement of quality and enlargement of a sales chain of flesh fish, and evaluate the economic ripple effects of the projects on fisheries communities as the project site and on the consumption areas. Thirdly, we propose the effective development methods of those projects on collecting and shipment places of fishing products which are not only flesh fish but also processed, as the project sites.

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Consumers as well as producers are highly aware that the quality control and hygiene management of fishery products is a priority matter. The authors have conducted an analysis on the economic impact of quality control and hygiene management of fishery products in the fishing port, which is a center of the landing areas, by employing the Input-Output table. The advanced cases in Hokkaido are deliberately selected for the analysis according to the major species. The results are as follows: 1) Exporting fishery products and supplying to the nation under quality control and hygiene management contribute to the recovery, stabilization and rise in value, in addition to expanding the market, 2) The economic effects far reach the whole country, especially consuming areas as well as landing areas. This paper also has clarified the validity of the fisheries infrastructure development in landing areas.

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Fishing ports play a vital role in maintaining and increasing fishery resources to secure stable supply of fishery products to the nation. The authors have conducted an analysis on the use of water areas of fishing ports in Hokkaido to enhance the functions of the port. The results are as follows: 1. An increasing number of fishing ports provide useful water areas for intermediate breeding, aquaculture and preservation of fish and shellfish, 2. The evaluation standards consist of the three steps: 1) To clarify the purpose, 2) To confirm the prerequisite conditions such as the current status of technology regarding to seedling production, breeding and aquaculture, 3) To evaluate the requirements such as waters' environmental conditions. 3. It is necessary to improve the existing conditions of waters, to create new water areas, or to multiuse water areas so as to strengthen the economic impact on the market.

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According to the Science Council of Japan, the multifunctional roles of fisheries and fishery communities are classified into 5 categories; 1) to provide foods and other natural resources, 2) to preserve natural environment, 3) to form and maintain local communities, 4) to protect people's lives and their properties and 5) to provide living and communication spaces to the people.
The authors have studied how the multifunctionality is recognized and aware of by the people of Hakodate City, where fisheries are prosperous. The study consists of the following three steps: 1. The correlations between the recognitions for the multifunctional roles and the awareness of the environments. 2. The value of the multifunctional roles of fisheries and fishery communities are estimated with the Contingent Valuation Method (CVM). 3. The research on the role to provide communication spaces between the urban and rural areas among the multifunctional roles are deepened.

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Yung Fishermen in MINAMIKAYABE Hakodate city Hokkaido have started aquaculture tangle by owner system at 2003. The owner system of aquaculture tangle is that consumer become to be owner of tangle juvenile, after maturity tangle is harvested, those tangle is processed and directly distributed to the owner.
The owner can access to the website which distributes the information about growing tangle. The authors suppose that the number of becoming owner is depended on access number to website. Then how does the access number to website change by media sorts informing owner system. There are many media sorts, those are television, radio, newspaper, word- of- mouth and postcards. How does the number of access to website depend on renewal method. The effective media sorts and renewal method of website are studied. As the result, the words of mouth and postcards are effective media and regularly renewal of website is effective for access number increasing.

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Yung Fishermen in MINAMIKAYABE Hakodate city Hokkaido have started aquaculture tangle by owner system at 2003. The owner system of aquaculture tangle is that consumer become to be owner of tangle juvenile, after maturity tangle is harvested, those tangle is processed and directly distributed to the owner.
The owner and consumer can access to the website that distribute the information about state of growing owner's tangle. The authors research what factors effect consumer intend to become the owner of aquaculture tangle. Factors are supposed to be confiding for owner system, utility for Website information, cost of tangle, closing between fishermen and owner by Website and owner ship of aquaculture tangle. Website questionnaires are done about factors of becoming owner and logistic multiple regression analysis. How do consumer decide to be tangle owner?. The effective business model with website is studied. As the result, fishing village is promoted by gaining merit of directly distribution.

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Now it happened disguising and illegal indicating of fishery products, therefore the safety and security for fishery products are gotten in trouble. the authors have built the system that distribute the records of fishing and producing to consumer with QR-code and photograph cellular phone, and its system is utilizing for distribution of corbicula at ZYUUSAN lake, Aomori pref. in Japan. This is the case study about the corbicula distribution and appreciation in comparison between attached traceability system and without the system. Furthermore how influent to appreciation of fishery products with traceability system are investigated by questionnaires. Thereafter appendix new function of fishing ports is considered while IT system have been introducing to fishery industry.

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Working environment at fishery ports and harbors during the winter in cold, windy regions such as Hokkaido, is very severe for workers. Therefore snow and wind shelters have been constructed in Hokkaido. We analyzed the results of questionnaire survey to evaluate working environment before and after the construction of the shelters. We found that the work load has been eased or the work efficiency has been increased after the construction of the shelter. We also performed on-site observation at a shelter of Otsu fishery port constructed in Dec. 2007 to evaluate the performance of wind reduction due to the shelter. We did a trial calculation the effect of the improvement of the work environment by the shelter on that of the work efficiency.

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This paper presents explicit approximation formulas with high accuracy to implicit expressions and numerical integration-based estimates which often appears in the coastal engineering field. The implicit expressions are the dispersion relation (wave period and water depth-dependent wave length), a critical water depth formula for waveinduced initial sediment movement and a universal spectral moment-based width parameter in finite depth water. The integrated estimates are a minimum duration-fetch relation and a minimum fetch-duration relation in which the quantities are dimensionless. The developments enable rather accurate computation of the above-mentioned quantities by use of a hand calculator.

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The “guidelines for coastal landscape formation” was established in January 2006. The valueof coastal environment improvement was estimated by the CVM (Contingent Valuation Method) and the TCM (Travel Cost Method). Estimation was performed from the coastal landscape improvement of Kaike coast by shore protection works.. By the CVM, value was 110 million yen/year in Yonago City, and 470 million yen/year in Tottori Prefecture. According to TCM, value was 210 million yen/year. The value was the almost same value from two methods. The method was applied to the actual castal improvement works for shore.

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There are a variety of problems like environment protection, disaster reduction and efficient uses in coastal zone management. To support the decision making of coastal management, a questionnaire survey on individual preferences for coastal zone management was implemented in Kanazawa ward of Yokohama city from April to May, 2006. Public preferences for the coastal management in general are coastal environmental conservation and coastal disaster reduction. Specifically, “floating garbage and leaked oil”, “trees and sea grass”, “earthquakes”, “high waves and tsunamis”, “floods”, “sea port”, “service industry like restaurant”, and “coastal tourism and recreation” are the most preferred to be treated. A marginal willingness to pay for each goal of coastal management is obtained, and the statistically significant interrelationships in the tradeoff between the attributes of coastal management were also clarified. These findings suggest the directions for re-allocating social resources, and the potential tradeoffs between goals based on costbenefit analyses.

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The aim of this study was to investigate a runup height of drifting litter due to waves on the cross shore between shoreline and sea embankment in the Fuji coast. Field investigations were performed by photographically recording debris in 3m×2m quadrilateral areas using a digital camera along transects extending from the shoreline to the sea embankment on a section of sandy beach. The number of drifting litter on the quadrilateral area was counted from the personal computer display inputted digital photograph, and arranged graphically by relating to the cross shore section. As the result it was found that, (1) the cross shore distribution of litter is not uniform and has a few peaks, (2) that the litter runup height at the first peak in the nearest shoreline is indicated with the surfsimilarity parameter using the maximum wave characteristics selected from the order of wave height before the field survey through the one year observed wave-record.

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This research is for cost analysis on refining and recycling treatment of marine drifting and landing debris from fisheries wastes. The experiments of refining treatment of plastic debris and expanded polystyrene debris were executed in Tsushima Island where huge amount of debris are drifted. Plastic debris was crushed and its volume was diminished to 15%. Expanded polystyrene debris are diminished to 5% by ester solvents. The diminish of debris volume can decrease the transportation cost and enable the material recycle. The total cost of diminishing debris is almost the same as landfill disposal. However, this cost is not acceptable for us. Because we use the crushing equipment of small type, we had to cut down by hands before using refining machine. Cost analysis result shows that more expensive refining machine that refine plastics without pretreatment may reduce the total cost.

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The phenomenon that is called water bloom and a red tide has happened in the waters advanced by eutrophication. This phenomenon causes damage of mixing with the fishery damage and the drinking water. Moreover, the exoticism that mixes with the ballast water influences the sea area environment. The treatment technology to solve such damage has not been established. It thought about the action of pressure, and the cell destruction was examined the destruction of the cell in this research. As a result, the rate of pressure change was large, and more the action frequency was, the more effective to the cell destruction was clarified. It has been understood that not only the gas vacuole but also the cell can be destroyed by using the water hammer pressure, and the effect of destruction improves remarkably.

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