Gozo Tsujimoto

A Design Method for Double Slit-Wall Breakwaters

A goal reflection coefficient is chosen to be K(sub r) = 0.4 and a design method for double slit-wall breakwaters with double slitted front walls, which has optimum dimension from a viewpoint of low wave reflection in wider frequency range, is proposed in the present study. The procedure of the design method is based on a numerical calculation with the Boundary Integral Method developed by the authors. In the procedure, important parameters affecting the goal reflection coefficient from the viewpoints of construction coasts are introduced explicitly.

ANALYSIS OF MEDIUM-TO LONG TERM VARIATION OF WATER QUALITY IN SETO INLAND SEA

Seto Inland Sea is the largest enclosed coastal sea in Japan. This sea is greatly influenced by incoming rivers and nutrient concentration sometimes makes the area susceptible to unusual events, such as red tide. In this paper, to clarify the contributing factors for the variation of water quality in Seto Inland Sea, EOF (empirical eigenfunction) analysis was applied to the monitoring data of COD (Chemical Oxygen Demand), T-N (Total nitrogen) and T-P (Total Phosphorous), which obtained form 1982 to 2001. Main results are as follows: 1) The first principal component which is obtained by EOF analysis reflect the effect of load form incoming rivers. 2) The second principal component may have some connection to the variation in main channel area (Bisan Seto area). 3) The variation of water quality in Seto Inland Sea can be described by using top three principal components.

STUDY ON HABITAT NETWORK OF FIDDLER CRAB Uca lactea IN HYOGO PREFECTURE

The ecological network formation of Uca lactea which is one of the Near Threatened species in Red-data Book published by Japan Environment Agency was considered. Study site is the tidal flats in Awaji Island which is located between Hrima-Nada, Osaka Bey and Kii Channel and around there. In this study, first, to confirm the habitat distribution of Uca lactea in Awaji Island, field observations were carried out. Secondary, to examine the possibility of the ecological network formation of Uca lactea around Awaji Island, the numerical simulations were run. Main results are as follows; 1) The habitats of Uca lactea in Awaji Island distributes on both east and west sides of Awaji Island. 2) In some of the habitats of Uca lactea in Awaji Island, the alternation of generations might be proceeding. 3) There is limited possibility that the movement of Uca lacteas larvae can reach to other habitats which is located across-the-sea neighbor in one month.

HOW TO UTILIZE COASTAL PRIMARY PSYCHO-SCENES FOR COASTAL IMPROVEMENT WORKS

It has been getting important recently to take a local residents request into consideration for coastal improvement works. Based on the questionnaire survey for the coastal primary psycho-scenes, items that related to the coastal primary psycho-scenes were studied. The items have four types; activity in amenity spaces, things and natural phenomenon, five physical senses and Kansei(sensitivity). Since the people can become pleasant when seeing beautiful scenery, this sensitivity was defined as Kansei and its strength as Kansei point. The Kansei points could be estimated by using the each items It was found that a correlation coefficient for the five senses and Kansei point was high. The common items related to the coastal primary psycho-scenes are as following: waves, bridges rock and evening sun.