China is not only a large ocean transport country, but one with a large inland river transportation, endowed with as many as 5,800 rivers, over 400, 000 kilo meters in length, and with a cruising range of more than 110,000 kiIo meters, about three times of the total length of that of Britain, France and Germany. All the main navigable rivers are spreading over in the economically developed zones and densely populated areas and flow from the west to the east, finally converging into the ocean, which are quite favorable for river-sea transportation. However, as the present vessels are miscellaneous in type and a large number of non-standard ships (especially concrete vessels and outboard-motor vessels) are operating on inland rivers, water accidents frequently occur, which seriously affects smooth navigation and compromises the efficiency of inland river transportation, making it much lower than that of the developed nations in the world. In recent years, the noise-making outboard vessels have become a fo China is not only a large ocean transport country, but one with a large inland river transportation, endowed with as many as 5,800 rivers, over 400,000 kilo meters in length, and with a cruising range of more than 110,000 kiIo meters, about three times of the total length of that of Britain, France and Germany. All the main navigable rivers are spreading over the economically developed zones and densely populated areas and flow from the west to the east, finally converging into the ocean, which are quite favorable However, as the present vessels are miscellaneous in type and a large number of non-standard ships (especially concrete vessels and outboard-motor vessels) are operating on inland rivers, water accidents frequently occur, which seriously affects smooth navigation and compromises the efficiency of inland river transportation, making it much lower than that of the developed nations in the world. In recent years, the noise-making outboard vessel s have become a fo