不影响超声的图像分辨力的因素是() A.超声频率与波长 B.脉冲的宽度 C.旁瓣数目

题型:单项选择题 A1/A2型题

问题:

不影响超声的图像分辨力的因素是()

A.超声频率与波长

B.脉冲的宽度

C.旁瓣数目的多少

D.声束的宽度

E.声场的远区和近区

考点:超声波医学主治医师2016版主治医师(超声波医学)基础知识考前冲刺五
题型:单项选择题 A1/A2型题

己知y=f(x)是定义在R上的奇函数,当x>0时,f(x)=loga(x+1)(其中a>0且a≠1)

(1)求函数y=f(x)的解析式;

(2)当x为何值时,f(x)的值的小于0?

题型:单项选择题 A1/A2型题

作者长期专业从事古文字研究和《说文》研究,对古文字研究成果和汉字形体发展演变脉络清楚,这一学养确保了作者在考正过程中能把学界最优秀的研究成果引证到考正中来。如黄字,许慎释其本义为“地之色也”,构形分析为“从田,从,亦声”。并认为是古文光字。后来人们在利用古文字材料研究黄字构形过程中曾提出不少新说。“考正”作者仔细考察诸说,联系黄字形体发展演变的实际,确认唐、裘所说是正确的。 对这段文字概括准确的是( )。

A.考正过程中于诸说抉择精审

B.古文字材料取用准确

C.多字的研究,形体追索到初文

D.独到的发明,每每可见

题型:单项选择题 A1/A2型题
任务型阅读(共10小题;每小题1分,满分10分)
请认真阅读下列短文,并根据所读内容在文章后表格中的空格里填入一个最恰当的单词。
注意:每个空格只填1个单词。
The Hong Kong government is set to overhaul(革新) its immigration policy with the aim of making it easier for mainland and overseas talents to live and work in the city. This is a welcome step because it will remove what is widely seen as a major hurdle to Hong Kong’s efforts to attract qualified immigrants to help its development.
To sustain the growth of the services sector, which accounts for nearly 80 percent of Hong Kong’s GDP, it is necessary to continuously expand the pool of talents in various fields. Efforts to attract mainland and overseas talents to Hong Kong are taking on special urgency not only because of fierce competition from other cities, particularly Singapore, but also the rapidly aging population resulting from years of low or negative birthrates.
Hong Kong enjoys certain distinct advantages over many Asian cities in the competition for talents. Beyond its vibrant economy, underlined by a free market environment, Hong Kong has a combination of some of the most distinctive elements of Chinese and Western cultures. Hong Kong is as exciting as many other Asian boomtowns, and yet it is no less efficient than a typical European city with a much smaller population. Housing costs are high, but no higher than those in other financial centers. For international banks and multinational corporations, housing costs are a concern only when the opportunity to make money begins to dry up. And this situation is not happening in Hong Kong as the local economy, riding the boom on the mainland, is rapidly expanding.
It is within this context that the government takes the lead to revise its immigration policy, which calls for, among other things, the establishment of a one-stop service center to process all applications under various migrant schemes. This means that an applicant will in future need to submit only one form for processing. Other changes to the policy include the removing of the age restrictions and lowering of experience requirements. Under the present scoring system used to vet applicants, those who are older than 50 and those with less than five years of work experience win no points in their respective categories. The details of the proposed changes have not been announced. But according to a government official quoted by the local press, the aim is to broaden the pool of qualified applicants.
The HK government’s revising its immigration policy
Aims
It aims to (56) _______ the pool of qualified immigrants and attract talents to help its development.
Reasons
Other Asian (57) _______ cities bring great pressure on it.
Low birth rates (58) _______ about rapidly aging population.
Advantages
It has a (59) _______ market environment.
It (60) _______ elements of Chinese culture and those of Western cultures.
It is as (61) _______ as a typical European city.
(62) _______ with other financial centers, housing costs are not
a concern due to the boom on the mainland.
Changes
Applicants will need to (63) _______ in only one form for processing.
The age restrictions are (64) _______.
Experience requirements are (65) _______.
题型:单项选择题 A1/A2型题

平面结构在荷载作用下的位移是由什么变形产生的?()

A.弯曲变形

B.轴向变形

C.剪切变形

D.扭转变形

E.刚体运动

题型:单项选择题 A1/A2型题

机坪管网高点排气装置的作用是排出管网内气体,确保加油计量准确。

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