( 3 ) presenting in - depth research and discussion on the solution of the 2 puzzles by taking ais information as the data - source of aas . ( 4 ) researching on the acquisition and processing method of basic navigation data from ais , such as relative course , relative speed , distance , bearing , cpa and tcpa of target ship . ( 5 ) designing the abaas ( ais based automatic anti - collision system ) collision avoidance scheme and establishing the principle of collision avoidance of own ship and designing the new principle of actions for the collision avoidance using the news data of ais according to the international regulations for preventing collisions at sea , 1972 , by calculating the risk of collision and consideration of the division of the three kinds of ship encounter 对于基于ais的自动避碰决策方法进行了深入研究，分析了国内外专家对于碰撞危险度的研究成果，并提出了确定碰撞危险度的方法；借鉴国内外专家的见解，对避碰规则规定的三种会遇局面进行了定量的分析并对避碰行动局面进行了划分；提出了互见条件下两船会遇中本船避碰责任和行动判断的原则；制定了两船会遇避碰方案和多船会遇避碰方案；针对从ais得到的他船航行状态信卜汕灯运学1 ； t帧卜学位论义杜十川s的船舶自动避陇决策系统的应用研究，以设zf了符合现则欲八条大十船舶m灾仟的避碰原则方沾。
In a word , it is the purpose and significance that , by discussing the questions , the article will provide a kind of theoretic thought for the judicial practice on establishing a set of self - contained and equitable system of burden of proof in collision actions between ships . so far , there is no maritime statute regulating the burden of proof of the plaintiff and defendant in collision cases of ships , furthermore , few theories about it in academe in our nation 同时，应该深入研究主宰碰撞领域的国际大法《 1972年国际海上避碰规则》及其修订本的各项规定，以便为我国司法界形成一套完备的，以民诉法中举证责任制度为原则但又具船舶碰撞诉讼特色的，兼顾船舶碰撞案件审理的涉外性和特殊性，公正均衡的船舶碰撞举证责任制度提供一种理论思路，此乃本课题研究的目的和意义所在。
The research works of this paper can be mainly demonstrated in the following aspects : 1 new model of dangerous degree of collision avoidance ( ddca ) was studied to determinate the best scheme of collision avoidance ; 2 ten factors , which affect the avoiding effect , were discussed in details ; 3 changing rules of dcpa and tcpa were discussed , according to the international collision avoidance rules at sea , under the following three circumstances : cross situation , head on situation , as well as overtake situation ; 4 to focus the discussion on cross situation 2 、确定影响避让效果的十大因素，将其产生的影响以行动时机提前量来消除。 3 、将船舶会遇局面按国际海上避碰规则所划分的交叉相遇局面、对遇局面、追越局面三种局面分别讨论dcpa和tcpa及其变化规律，结合船舶碰撞危险度评价并确立最佳避让方案。 4 、将交叉相遇局面作为本文的研究重点，对遇局面和追越局面可以视作交叉相遇局面的特殊情况来处理。
Making a comprehensive survey of the developing shipping technology history , there are mainly two ways to increase the security of the vessels " navigating in the sea recently : one is depending on the vts when ships arrive at harbors ; the other one is depending on the rules of vessel collision when ships navigating in the sea 纵观航运技术发展的历史，为了提高船舶航行的安全性，目前主要采取两个方面措施，一方面是船靠港时依赖于船舶交管系统vts ，另一方面是船与船操作时依赖于船舶避碰规则。
