海洋科学数据是典型的多源异构三维空间数据,其特征为数据的管理、应用与共享带来了困难.本体作为一种可共享的、明确的、规范化的说明,是处理异构数据的一种有效手段.以构建海洋科学数据本体为目标,首先梳理了海洋空间本体的构建流程.然后针对流程中的两个核心步骤进行了创新和改进:①为更完整地表达海洋空间本体中的对象属性,在海洋科学数据空间关系描述中,从海洋水深角度出发,提出了考虑内部划分的三维方位关系模型,并对维数扩展9交矩阵模型(dimensionally extended nine-intersection model,DE-9IM)取值进行了三维扩展,使其能够准确表达三维对象之间的拓扑关系.②根据丰富后的海洋科学数据空间关系,设计了适合该本体推理的空间规则集.最后以国家极地科学数据为例,搭建了考虑三维空间关系的海洋科学数据本体库,并从数据检索的查全率与查准率两方面证明了该本体的有效性.

在麦穗鱼鱼群中,随着邻居鱼的靠拢,其影像在本鱼眼睛中占的视角会变大.为了进一步探究其他的鱼群是否也存在相同的规律,本实验选用个体体长较小的喜成群的红吻半线脂鲤[由30尾组成,平均体长:(20.3±0.2) mm]作为对比研究对象,将其放置在水深5 cm的水族缸(78.0 cm×52.0 cm×65.0cm)中,使用摄像机从正上方拍摄鱼群影像.逐幅提取鱼群影像中各个体的头部、质心(近头部1/3处)、尾部的二维数据,经过数据处理,分析视角与NND间的关系.结果表明:1)红吻半线脂鲤与麦穗鱼的视角均集中在80°内,即本鱼观察邻居鱼的视角不大于80°.2)在体长差异较大的两种鱼群中,邻近个体占据本鱼的视野范围不会因为鱼体的增大而增加.3)邻近个体占据本鱼视野的最大视角与二者NND间满足以下关系:xy=A,y为视角(用弧度表示),x为NND(单位:BL),A为常数.该规律适用于麦穗鱼与红吻半线脂鲤群体.4)该关系式表示,当邻居鱼靠近本鱼时,为了避免碰撞,鱼类个体用视角作为控制的主要参数,调整相互距离.研究表明,视觉在起主导作用,而侧线、嗅觉、电感觉、磁感觉等即使起作用,也处于次要的地位.

为了探究麦穗鱼群体动态结构的特征参数,以及这些参数可能反映的行为机理,本实验使用2台摄像机从俯视和侧视2个方向同时拍摄由13尾麦穗鱼组成的群体,获取连续时间内麦穗鱼群体中各个体的三维位置数据,对个体间最近邻近距离、视角、转角变化量、个体游泳速度等参数进行分析.结果表明:麦穗鱼个体最近邻近距离多数处于0.5 ～2 BL,偏好的最近邻近距离为0.6～0.8 BL;麦穗鱼总是将最邻近的个体保持在本鱼80°视野范围内;避免碰撞时,个体鱼转角改变量为0 ～30°;在无人为干扰的自然环境下,个体鱼以0.75 BL/s左右的速度配合其他个体保持运动速度一致性.实验观察证实,视觉对麦穗鱼个体间的分布起着关键性作用,此外麦穗鱼群体动态结构还受到个体状态(饱食与饥饿)的影响.

Archaeological excavations of the Bao'en Temple and the underground palace of the North Song Dynasty was one of the ten greatest archaeological discoveries in 2010.Many artefacts were unearthed from the underground palace,which have profound historical significance. This paper studies how one glass bowl(TN5) was repaired based on the results of initial research and screening materials test.The bonding materials used for TN5 are Paraloid B72,and pouring material is a kind of epoxide resin(Araldite 2020#).After the conservation and restoration,the glass bowl restores its original appearance and reserves its historical information to the great extent.

According to the video records of spatial distribution of individuals in the fish school taken in the lab,the distances among individuals in fish school measured and calculated by the body-centroid method(BCM),segment method(SM) and broken line of three point method(BLM) indicate that the most of distances are varied in the range of 0.5-2 times body length(BL) while the number of individuals increasing to a certain level.The results by SM were basically same as the one from BLM,and the precision of BCM was lower than the others.When the body length was greater than 0.2 BL,the frequency of distance appearance of BLM was generally higher than SM’s and its result was more precise.And the distances calculated by means of the SM and BLM were mostly allocated in the range of 0.6-0.8 BL,which revealed that the range might be the preferred distance of the fish.