In particular , with the diameter of titanium dioxide nanosized , titanium dioxide behaves in some unique properties such as good ultraviolet absorptivity , transparence and harmless , special color effects , and photocatalytic activity 特别地，二氧化钛纳米化以后，由于其粒径小、比表面积大、界面原子所占比例大而具有更为独特的性能。如优异的紫外屏蔽作用、透明无毒、独特的颜色效应及光化学催化作用等。
So the conception of los ( light of sign ) is introduced into the equivalent treatment of treat avoidance in order to take account of terrain - shiled affection . finally , a new genetic algorithm is developed in this paper . three new arithmetic operators which are introduced into the algorithm are recording better , restoration and reconstruction . what ' s more , the known arithmetic operators are also improved in order to expand searching scope 因此在对威胁回避的等效处理上，本文引进了los (视线)概念进行地形可视概率计算，把威胁回避等效为地形回避，然后把等效地形数据离散化叠加到原先的地形高程数据中，这样就充分地考虑了地形的屏蔽作用。
It is found : ( 1 ) when the current direction is close to that of the line through the two caissons ' centers , the current speed within the area between the double caissons apparently decreases ; ( 2 ) sea ice ride - up and pile - up against the outer side of the caissons are similar to that against single caisson , and sea ice ride - up and pile - up are determnined by the sea ice velocity , sea ice thickness , tide and the storm set up ; ( 3 ) when locate two caissons , the tops of the two caissons in the shield area are no ice covered 研究发现： ( 1 )当海流流向与双沉箱的中心连线相近时，双沉箱对峙区的流速明显减小； ( 2 )双沉箱外侧区域的海冰爬升和堆积与单沉箱时基本相同，其爬升和堆积与海冰的速度和厚度、天文潮高等有关； ( 3 )双沉箱设置时，对海冰爬升和堆积会起到有效的屏蔽作用，对峙区内的双沉箱顶上不再有海冰堆积。
Firstly , this paper summarizes modern weaponry stealth technology at home and abroad , and lays special emphasis on analyzing stealth problem of cruise missile ’ s guidance head cover , aerocraft radar canopy and other privileged sites . secondly it makes a research on related theories of transparent metallic mesh that applied to missile ’ s guidance head cover and aerocraft radar canopy , and deduces relational expression between transparent metallic mesh structural parameters and radar wave - shielding efficiency , infrared transmitting . we use laser direct writing technique to fabricate a metallic mesh ( dimension : 70mm 70mm ; line width : 5 m ; period : 350 m ) on glass surface , then do experiment to test radar wave - shielding of metallic mesh via radar transmitting and receiving device 本文首先综述了国内外现代武器系统隐身技术方法;重点对巡航导弹导引头罩和飞机雷达舱罩等特殊部位的隐身问题进行了研究,研究了金属网栅用于导弹头罩和飞机雷达舱罩隐身的相关理论,推导了金属网栅结构参数对雷达波屏蔽效率和透红外关系式;用激光直写工艺,在玻璃表面上制作了一块面积为70mm 70mm ,线宽为5 m ,线周期为350 m的金属网栅;在实验室里用雷达发射和接收装置测试了网栅对雷达波的屏蔽实验;认为利用金属网栅技术对雷达波具有一定的屏蔽作用,而且不影响精确制导的红外线高效透过。
