【判断题】相对定位是用两台接收机分别安置在基线的两端,同步观测相同的GPS卫星,以确定基线两个端点的绝对坐标。
【多选题】有关材料分类不正确的是 [ ]
B.
高温结构陶瓷属于新型无机非金属材料,金属属于金属材料,但都属于结构材料
C.
新型无机非金属材料包括半导体材料、光导纤维、氧化铝陶瓷等
D.
氮化硅陶瓷属于新型无机非金属材料,但不是高温结构材料
【单选题】C In most situations, light helps us see. But nowadays humans are using too much of it so that it is in fact a kind of pollution. When it comes to looking at the night sky, too much light makes it dif...
A.
Because there are fewer and fewer stars.
B.
Because human health has been affected.
C.
Because too much light is a waste of energy.
D.
Because some of the wildlife can be harmed.
【多选题】炭疽的下列哪种情况需要进行报告()
D.
1周内、同一学校、幼儿园、自然村寨、社区、建筑工地等集体单位发生3例及以上皮肤炭疽或肠炭疽病例
【多选题】隧道道施工过程中,当遇到软弱破碎围岩时,其自支护能力是比较弱的,经常采用的预支护措施有()等。
【简答题】A.Planktons are too small to be seen. B.Most planktons have transparent tissues. C.Most planktons are practically invisible to predators. D.Planktons are fascinating organisms.
【简答题】静态相对定位是指在作业过程中,利用两台以上接收机分别安置在基线两端在静止状态下同步观测GPS卫星获得充分的观测数据,经过数据处理确定基线两端点的()。