A bathymetric chart is a basic and useful tool for any study field in ocean science, and it is generally mapped from bathymetric data by multi narrow-beam echo-sounder (MNBES). However, MNBES is still expensive and inconvenient to utlize on a small boat at shallower coastal water e.g. shallow coral reef. Meanwhile, recently accuracy is improved both in location of GPS and in depth of fish finder (single echo sounder). This paper proposes a facile method for mapping bathymetric chart at shallow coastal water by using data of GPS and fish finder. Sea trial with GPS and fish finder was carried out at shallow water in Tateyama Bay, Chiba Prefecture, and the bathymetric chart was mapped by a 3D rendering software. The obtained bathymetric chart was compared with that mapped from data of MNBES, and data amendment was examined. This method can express the shape of the object on seabed of which dimension was twice larger than the distance between the successive two sounding points. The depth data should be amended, considering time change in tidal level and boat motion due to wave generated by other ships. The sounding points are concentrated on the boat track line, and thus introduction of anisotropic friction is effective in interpolating depth data between the track lines for 3D rendering.

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In order to quantitatively clarify the change of prey animals with artificial reef installation, we have investigated the distribution and the seasonal variation of epiphytic algae and small animals on and around the reefs in two sites, Seto Inlands Sea and Sea of Japan, for two years. As results, amphipods had majority as phytal animals and their seasonal prevalence followed the lifecycle of algae on the reefs. Important prey animals such as decapods were observed in the reefs with various rooms among materials. These prey animals were less observed in the no-room reefs consistently. Benthic animals increased by the bottom sediment variation due to reef installation. Furthermore, not only sessile and infiltrate animals inhabiting reef materials but phytal animals inhabiting epiphytic algae were additionally observed. Zooplankton around the reefs were gathered and scattered by currents. These suggests the followings ; 1) many small animals classified as prey item for fish make biological reprogical reproduction at reef ecosystem, 2) to make many various rooms in the reef is effective for production of small animals, and 3) these animals made their biota complicate by spreading or migrating around the reefs. It's also suggested that the site characteristics and reef materials have species variety, biomass and distribution range.

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This paper proposes the multi-criteria evaluation method of projects for the fisheries infrastructures and analyzes the benefit of those projects with this method. This paper, first, studies characteristics and issues on the cost-benefit analysis which is the current evaluation method for the fisheries infrastructures and on the integrated estimation method with the multi-criteria evaluation which applies the various evaluation categories to evaluate the projects and evaluates the projects with the five grades on the every evaluation categories. The integrated estimation method also, with input-output analysis, evaluates the economic ripple effects of the projects on the project sites and on the areas which the project influences as well as the cost-benefit rate. Secondary, this paper studies the benefits of the projects for the fishery infrastructures with the integrated estimation method and evaluates the economic ripple effects of the projects on fisheries communities as the project site and on the consumption areas and studies those relations.

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本研究では水産物の流通における品質管理に資することを目的として,魚市場の競り人による鮮魚の外観評価に着目し,これと等価なモデルを設計することを試みている。試料魚には競り人により計5群に外観評価されたシロサバフグ計269尾(6〜8尾入り/箱,計35箱)を用いた。競り人の外観評価,魚体体表の色彩及び魚肉鮮度の関係を統計的手法により解析した結果,魚体体表上に設定した計4個の色彩の指標が外観評価及び魚肉鮮度の程度を良く反映することが明らかとなった。これらの指標を言語規則の前件部変数に用いて構成したファジィ推論モデルをシミュレーションと実験により評価した結果,競り人の評価とモデルでの推定結果とが一致した割合はともに96%以上となり,モデルの高い有用性が示された。

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In 2005 and 2006, the study for fish propagation effects on artificial fishing ground was conducted to understand the reef effect for the marbled sole Pleuronectes yokohamae and its distribution pattern around artificial reefs. The study was undertaken in about 4 to 9 mater depth of two different coastal waters. In early spring, juvenile of marbled sole, 1.5 cm in average size, were observed in the artificial reef zone located in the coast of Hinase city in Okayama prefecture. The distribution density was particularly higher within 4 meters range of the artificial reef. In the coast of Noto city in Ishikawa prefecture, the densities of immature and adult individuals were higher in artificial reef zone as well. It is also observed that once marbled fish transits to the demersal stage, it mainly preys on organisms derived from artificial reefs. Small organisms aggregated around artificial reefs were main component of stomach contents from juvenile and over one year old marbled sole collected around artificial reefs. Artificial reef seems to function as a feeding ground for marbled sole of demersal stage. This study clarifies that artificial reef positively improves the survival rate of marbled sole by providing food organisms; bence it can enhance resorce propagation of this species.

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"Rolling chock" is a plate-like hull appendage just below the waterline on small-scaled fishing boat (less than 20 GT), and is expected to play a role of damping effect on the rolling motion by fishermen and shipyard engineers with their empirical knowledge. It was assumed that the resistance produced by the rolling chock in the rolling motion is a main factor of the damping effect. Few studies have however been done on damping effect of the rolling chock. This study confirmed the damping effect of the roling chock in the tank tests by using a model ship of Lpp 1.92m with rolling chock of three different widths (0.01, 0.02, and 0.04m) and without. In this study, the damping effect is assumed to be evaluated by the wave-making component of ship resistance. The damping of the rolling motion measured in free roll tests was modeled with the single-degree-of-freedom rolling equation, and then the extinction coefficients were determined by Froude's energy method. On the coefficients, wave-making component b_<F1> of the model ship equipped with rolling-chock was larger than that without rolling chock, and increased similar to the extinction coefficient as the rolling chock became wider. In contrast, no particular relationship of vortex-making component b_<b2> to rolling chock width was found. The maximum resonance amplitude was clearly reduced with equipping the rolling chock in rolling tests in beam waves of three wave slopes (1/10, 1/20, and 1/30). Linear model substituted into damping moment term of the single-degree-of-freedom rolling equation was valid to express the maximum resonance amplitude of the model ship with and without rolling chock.

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Fuel consumption of main engine for fishing vessel was measured in order to evaluate the effectiveness of the warming-up and the avoidance of the rapid increase in load. the results showed that warming-up of main engine was effective in the fuel-saving, however, the operation for warming-up should be stopped in the minimal time and the load factor of main engine should be slowly increased after the leaving at port; the operation with the rapid increase in load was made to increase the fuel consumption, the increasing rate of fuel consumption was lower than that in case of the warming-up.

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We examined the change in hardness on the surface of sand according to the level saturation and unsaturated of the shore line region, and investigated the relation between the sand hardness and the occurrence of the gammaridean amphipod Haustorioides japonicus at Niigata, Japan Sea coast of the central Japan. On the shore, the hardness of unsaturated sand was 3 to 7 times higher than the hardness of saturated sand. This indicated that sand hardness changed alternately at the same point on the shore according to the saturated and unsaturated level by the seawater supply due to the effect of wave action. Laboratory experiments revealed that the number of individuals H.japonicus exposed on the surface of sand increased with the increase in sand hardness due to the decrease of the level of the saturated water in the experimetal sand substrate. These observations suggested that the increase of hardness on the surface of unsaturated sand obstructed burrowing activity of the H.japonicus in the sandy substrate, which then increased the risk of desiccation and predation by birds.

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Using input-output table of fishing villages enables the slogans clear in value, which were ambiguous and politics for the contribution to the regional society, region revitalization, region development. That means it can materialize the future visions, scenarios and efficient infrastructures. While the future visions and scenarios are promoting, it is possible to check progresses the policy of visions according to trace the present economic indexes. This report explains the method of analysis for the future economic effectiveness of fishing villages and fisheries by using input-output tables.

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