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【单选题】

Passage One
The oceans, which cover nearly three-quarters of Earth’s suce, remain largely unexplored because of their vastness and inaccessibility to us air breathers. Webb Research of East Falmouth, Massachusetts, hopes to open up much of that mystery field with a new underwater vehicle that is pushed ahead solely by the ocean itself, so it can potentially study the watery depths for years at a time. Such long-lasting detectors may someday form fleets that provide up-to-minute data for weather forecasting.
In the past, such autonomous underwater vehicles, or AUVs, have been battery powered and therefore required frequent recharges that limited their distance and depth of travel. Webb’s Slocum glider(滑翔机) hopes to solve this problem. "We conceived of a thermally powered engine to get the energy from the colder deep water of the ocean and the shallower warm water," Clayton Jones, an engineer at Webb Research, explains. "We picked out a material that undergoes a state change between those two temperatures in the ocean." When cold, this form-shifting substance is a compact solid. When warm, it expands and becomes a less dense liquid. The material’s expansion in warmer waters charges an internal mechanism that acts like stored power to control its buoyancy: by pumping mineral oil in and out of an external air bag, it alters its volume but maintains its weight. "The glider takes up more volume and becomes lighter than the water around it--less dense," Jones says.
Scientists can also fit the Slocum glider with a variety of different sensory equipment and Global Positioning Systems. Each time it suces, it can raise its tail antenna(天线) to transmit data to and receive instructions from researchers sitting comfortably in their cozy offices. The glider will have its first test in salt water at the end of this September.
The gliders could also get through and follow previously unstudied phenomena such as small underwater eddies (漩涡), which are vital to understanding water transport and heat flow in the ocean and therefore play an important role in storm formation and other weather development. "We have all these data snapshots(快照) from floats that just flow with the deep ocean current," Jones says. "To be able to fly through eddy sections, then transport with the whole eddy itself as it moves through the ocean, would be a very nice phenomenon to take a look at."
According to the text, the Slocum Glider will possibly be used to ______.

A.
change the occurrence patterns of underwater eddies
B.
control storm formation and other weather development
C.
show a vivid picture of the movement of the eddies
D.
guide planes to fly over the eddy sections to avoid er
题目标签:天线快照滑翔机
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举一反三

【多选题】在LTER8中,支持的天线模式有()

A.
发射分级
B.
开环MIMO
C.
单流波束赋性
D.
双流波束赋性

【单选题】下面对搜索引擎的“网页快照”说法正确的是( )

A.
网页快照就是指把搜索引擎以前拍摄的网页照片显示出来
B.
当原始出处的网页被删除后,网页快照还可能显示所查信息
C.
网页快照是指用户拍摄的网页照片
D.
网页快照是存放在原出处网站数据库中的网页

【多选题】LTE网络支持的天线种类有:

A.
智能天线常规直线阵
B.
智能双极化天线
C.
智能天线圆阵
D.
分布式天线

【单选题】创建容器快照命令()

A.
docker commit
B.
docker ps
C.
docker-run
D.
docker

【多选题】以下哪个LTE天线方案不是仅支持单流?

A.
8天线Beamforming
B.
8天线2x2MIMO
C.
4x2MIMO
D.
AdaptiveMIMO/BF

【单选题】下列关于虚拟机快照的说法中,哪一项是正确的?()

A.
快照作为单个文件记录,存储在虚拟机的配置目录中
B.
虚拟机一次只能拍摄一张快照
C.
在拍摄快照过程中可以选择是否捕获虚拟机的内存状态
D.
只能从命令行管理快照

【单选题】为保证流应用的快照存储的可靠性,快照主要存储在:( )。

A.
本地文件系统中
B.
JobManager的内存中
C.
HDFS中
D.
可靠性高的单击数据库中

【多选题】以下关于快照的说法中,正确的是?( )

A.
使用历史记录控制板菜单中的新快照命令可以为图像建立多个不同的快照
B.
快照可以用来存储图像处理过程中的状态
C.
快照中可以包含图像中的图层、路径、通道等多种信息
D.
下次打开图像时,建立的快照仍会出现在历史记录控制板中

【多选题】以下天线说法正确的为:()

A.
dBm是一个考征功率绝对值的值,计算公式为:10lgP(功率值/1mw)。
B.
dBi的参考基准为全方向性天线,dBd的参考基准为偶极子,用dBi表示出来比用dBd表示出来要小2.15。
C.
甲功率比乙功率大一倍,也可以说,甲的功率比乙的功率大3dB。
D.
在天线方向图中,功率相差3dB点为天线的半功率点。

【多选题】MIMO 天线可以起什么作用?

A.
收发分集
B.
空间复用
C.
赋形抗干扰
D.
用户定位
相关题目:
【多选题】在LTER8中,支持的天线模式有()
A.
发射分级
B.
开环MIMO
C.
单流波束赋性
D.
双流波束赋性
【单选题】下面对搜索引擎的“网页快照”说法正确的是( )
A.
网页快照就是指把搜索引擎以前拍摄的网页照片显示出来
B.
当原始出处的网页被删除后,网页快照还可能显示所查信息
C.
网页快照是指用户拍摄的网页照片
D.
网页快照是存放在原出处网站数据库中的网页
【多选题】LTE网络支持的天线种类有:
A.
智能天线常规直线阵
B.
智能双极化天线
C.
智能天线圆阵
D.
分布式天线
【单选题】创建容器快照命令()
A.
docker commit
B.
docker ps
C.
docker-run
D.
docker
【多选题】以下哪个LTE天线方案不是仅支持单流?
A.
8天线Beamforming
B.
8天线2x2MIMO
C.
4x2MIMO
D.
AdaptiveMIMO/BF
【单选题】下列关于虚拟机快照的说法中,哪一项是正确的?()
A.
快照作为单个文件记录,存储在虚拟机的配置目录中
B.
虚拟机一次只能拍摄一张快照
C.
在拍摄快照过程中可以选择是否捕获虚拟机的内存状态
D.
只能从命令行管理快照
【单选题】为保证流应用的快照存储的可靠性,快照主要存储在:( )。
A.
本地文件系统中
B.
JobManager的内存中
C.
HDFS中
D.
可靠性高的单击数据库中
【多选题】以下关于快照的说法中,正确的是?( )
A.
使用历史记录控制板菜单中的新快照命令可以为图像建立多个不同的快照
B.
快照可以用来存储图像处理过程中的状态
C.
快照中可以包含图像中的图层、路径、通道等多种信息
D.
下次打开图像时,建立的快照仍会出现在历史记录控制板中
【多选题】以下天线说法正确的为:()
A.
dBm是一个考征功率绝对值的值,计算公式为:10lgP(功率值/1mw)。
B.
dBi的参考基准为全方向性天线,dBd的参考基准为偶极子,用dBi表示出来比用dBd表示出来要小2.15。
C.
甲功率比乙功率大一倍,也可以说,甲的功率比乙的功率大3dB。
D.
在天线方向图中,功率相差3dB点为天线的半功率点。
【多选题】MIMO 天线可以起什么作用?
A.
收发分集
B.
空间复用
C.
赋形抗干扰
D.
用户定位