什么是仪表的误差？怎样表示？-我要搜题网

[不定项选择题]共用题干第二篇

Don't Count on Dung（粪便）

Conservationists（自然保护主义者）may be miscalculating the numbers of the threatened animals such as elephants,say African and American researchers. The error occurs because of a flaw in the way they estimate animal numbers from the piles of dung（粪）the creatures leave behind.
The mistake could lead researchers to think that there are twice as many elephants as there really are in some regions according to Andrew Plumptre of the Wildlife Conservation Society(WCS)in New York.
Biologist Katy Payne of Cornell University in Ithaca,New York,agrees,"We really need to know elephant numbers and the evidence that we have is quite indirect,"says Payne,who electronically tracks elephants.
Counting elephants from planes is impossible in the vast rainforests of Central Africa. So researchers often estimate elephant numbers by counting dung piles in a given area. They also need to know the rate at which dung decays because it's extremely difficult to determine these rates. However,researchers counting elephants in one region tend to rely on standard decay rates established elsewhere.
But researchers at the WCS have found that this decay rate varies from region to region depending on the climate and environment. "Using the wrong values can lead the census astray（离开正道）,"says Plumptre.
He and his colleague Anthony Chifu Nchanji studied decaying elephant dung in the forests of Cameroon.They found that the dung decayed between 55 and 65 percent more slowly than the dung in the rainforests of neighbouring Gabon.If researchers use decay rates from Gabon to count elephants in Cameroon,they would probably find more elephants than are actually around.This could mean estimates in Cameroon are at least twice as high as those derived from decay rates calculated locally,says Plumptre"However accurate your dung density estimate might be,the decay rate can severely affect the result."
Plumptre also says that the dung-pile census should be carried out over a region similar in size to an elephant's natural range.The usual technique of monitoring only small,protected areas distorts numbers because elephants move in and out of these regions,he says"If the elephant population increases within the protected area,you cannot determine whether it is a real increase or whether it is due to elephants moving in because they are being poached（入侵偷猎）outside."
Plumptre says that similar problems may also affect other animal census studies that rely on indirect evidence such as nests,tracks or burrows（地洞）. Why do researchers estimate elephant numbers in an area by counting dung piles?
A.Because elephants are difficult to catch.
B.Because it is not possible to count elephants from a plane.
C.Because it is not possible to keep track of elephants.
D.Because elephants are shy anitnals.

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[判断题]凡是进行高处作业施工的，应使用脚手架、平台、梯子、防护围栏、档脚板、安全带和安全网等。
A.正确
B.错误

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[单选题]下列各项中，不属于民用建筑的是（）。
A.商场
B.影剧院
C.体育馆
D.服装仓库

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[单选题] (单选题)唯物辩证法认为,发展是()
A. 事物永不停息的运动变化
B. 事物从过去到现在再到将来的变化
C. 事物由低级到高级的运动变化
D. 事物由小到大、由少到多的变化

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[单选题]女，50岁。双下肢水肿10余年，晨轻暮重，无眼睑水肿和泡沫尿。查体：BP130/70mmHg，双肺呼吸音清，心界不大，心率87次/分，心律齐。腹软，肝、脾肋下未触及，移动性浊音阴性。双下肢可凹陷性水肿，浅静脉呈蚯蚓状改变。该患者下肢水肿最可能的原因是（）。
A.下肢静脉压增高
B.血浆胶体渗透压降低
C.淋巴液回流受阻
D.血浆晶体渗透压降低
E.心肌收缩力降低

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[多项选择]艺术字工具栏包括哪些功能（）
A. 插入艺术字
B. 编辑文字
C. 艺术字形状编辑
D. 自由旋转

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[单项选择]确诊胃溃疡出血最可靠的方法是（　）
A. 胃液分析
B. 粪便隐血试验
C. 钡餐检查
D. 放射性核素检测
E. 以上均不是

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[单选题]下列哪项不参与共济运动:
A.前庭神经
B.视神经
C.锥体外系
D.小脑
E.大脑

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[单项选择]

Comparisons were drawn between the development of television in the 20th century and the diffusion of printing in the 15th and 16th centuries. Yet much had happened {{U}} (67) {{/U}}. As was discussed before, it was not {{U}} (68) {{/U}} the 19th century that the newspaper became the dominant pre-electronic {{U}} (69) {{/U}}, following in the wake of the pamphlet and the book and in the {{U}} (70) {{/U}} of the periodical. It was during the same time that the communications revolution {{U}} (71) {{/U}} up, beginning with transport, the railway, and leading {{U}} (72) {{/U}} through the telegraph, the telephone, radio, and motion pictures {{U}} (73) {{/U}} the 20th-century world of the motor car and the airplane. Not everyone sees that process in {{U}} (74) {{/U}}. It is important to do so.
It is generally recognized, {{U}} (75)
A. ability
B. capability
C. capacity
D. faculty

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[单项选择]某学生在研究事物时，容易受他人态度的影响，这位学生的认知方式很可能属于( )。
A. 场依存型
B. 场独立型
C. 冲动型
D. 沉思型

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[单选题]治疗瘰疬、瘿瘤等证的药物具有的药性是
A.苦味
B.甘味
C.咸味
D.涩味
E.淡味

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[单选题]( )指为了保证完成临时紧急任务的需要所储备的技术状态良好的国铁空货车。
A.路用车
B.自备车
C.备用车
D.抢险车

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[单选题]各车站均应配备与（）相当的手持金属探测器。
A.客流量
B.客流高峰
C.安检仪数量
D.安检工作人员数量

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[简答题]简述探找漏洞进口的观察出水颜色法。

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[简答题]什么是仪表的误差？怎样表示？

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