In Japan, there are a lot of bridges connecting islands. Particularly in the Seto Inland Sea, several bridges are constructed near the narrow channels. When we pursue the safe operation of the vessels, we consider it important to analyze the masking features of the radar images of such bridges and the reflection intensity.
In this study, we analyzed the features by the difference in the structure and the masking features along the direction of the width of the bridge and the reflection intensity about two bridges, in order to improve the safety of ships traffic.
Conventionally, the radar reflection intensity of a small object such as a small ship has been evaluated by the maximum signal intensity in the image. In this study, we tried a new evaluation method for the radar reflection intensity of the connecting bridges those are huge and strong reflection structures, and we report the result.
When strong stress is continued, it becomes the negative thought. It is said to suffer from depression or an internal organs disease. In stress, the person may not have the recognition of the symptom. It is hard to sometimes notice an accident. In this article, I performed an attitude survey of the stress for sailors and I performed a heartbeat experiment and stress index analysis. And I compared the stress degree with the scene subjected to stress. As a result, the place where sailors were in danger was a narrow channel and a port. When the congested situation and view were small, the situation confirmed high stress. When there was the uneasiness of a collision, sailors grasped that a stress degree tended to become higher.
The purpose of this study is to compare the tide level of 2 points at Osakikamijima island. This study is carried out the accessory study of an observation experiment for the tide level by onboard GPS. The results indicated there were few differences of the tide level in 2 points in the peaceful weather. And there were many differences of the tide level in 2 points in the rough weather. And authors observed the tidal wave by the 2015 typhoon No.15.
Risk-based maintenance (RBM) means that maintenance will be done according to the risk evaluation result, which is calculated by the probability of failure and the consequence of failure. RBM is often applied to some plants (oil refining plant, chemical plant etc...), but still few applied to vessels. IMC developed the RBM software for vessels in order to apply RBM to ship management, but the RBM calculation method and result is not enough to be verified. Therefore, we apply RBM to Hiroshima-Maru, and improve the RBM calculation method and result. In the future, we aim at the practical use of the RBM for vessels.