单选题The basic process of biological sewage treatment consists of the liquor either by bubbling air through it or by agitating the surface（）A oxygenatingB oxidizingC deoxygenatingD proportioning

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单选题

The basic process of biological sewage treatment consists of the liquor either by bubbling air through it or by agitating the surface（）

oxygenating

oxidizing

deoxygenating

proportioning

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相似问题和答案

第1题：

Theois designed with a primary combustion chamber for burning sludge oil and ／or solid waste, and two secondary combustion chambers for9ases.burning uncombusted exhaust

A.boiler

B.separator

C.incinerator

D.treatment lological sewage

答案：C

第2题：

The biological sewage treatment plant utilizes Oto completely break down the sewage into an acceptable substance for discharge－into anywaters

A.agitation function

B.bacteria

C.chemica

D.oxidizing function

答案：B

第3题：

X2AP基本过程包含『____』和『____』两类。(X2AP basic process consists of two types『____』and『____』.)

参考答案：Class 1
Class 2
Class 1
Class 2

第4题：

Biological treatment may use __ to treat sewage (1)living organisms (2)chemicals (3)additives

A.(1)

B.(2)

C.(3)

D.(1)(2)(3)

正确答案：A

第5题：

Why do dates require special treatment during the ETL process?

为什么在ETL的过程中需要对日期进行特殊处理？

正确答案：
答：在数据仓库的项目中，分析是主导需求，而基于日期和时间的分析更是占了很大的比重。而在操作型源系统中，日期通常都是SQL的DATETIME型的。如果在分析时，使用SQL对这种类型的字段临时处理会出现一些问题，如效率很差，不同的用户会采用不同的格式化方法导致报表不统一。所以，在数据仓库的建模时都会建立日期维度表和时间维度表，将用到的和日期相关的描述都冗余到该表中。
但是，并不是所有的日期都被转化为日期维度表的外键。日期维度表中的记录是有限的，有些日期如生日等可能会比日期维度表中记录的最小日期还要早，这类字段可以直接在数据仓库中保存SQL的DATETIME型。而像购买日期等与分析的业务紧密相关的通常都需要转化为日期维度表的外键，可以用日期维度表中统一的描述信息进行分析。

第6题：

Most marine biological sewage treatment plants consist of all the following statements except()

A.aeration tanks

B.settling tanks

C.disinfection agent(消毒剂

D.anaerobic bacteria(厌氧菌)

答案：C

第7题：

What are the four basic Data Flow steps of an ETL process?

在ETL过程中四个基本的过程分别是什么？

正确答案：
答：
Kimball数据仓库构建方法中，ETL的过程和传统的实现方法有一些不同，主要分为四个阶段，分别是抽取（extract）、清洗（clean）、一致性处理（comform）和交付（delivery），简称为ECCD。
1．抽取阶段的主要任务是：
读取源系统的数据模型。
连接并访问源系统的数据。
变化数据捕获。
抽取数据到数据准备区。
2．清洗阶段的主要任务是：
清洗并增补列的属性。
清洗并增补数据结构。
清洗并增补数据规则。
增补复杂的业务规则。
建立元数据库描述数据质量。
将清洗后的数据保存到数据准备区。
3．一致性处理阶段的主要任务是：
一致性处理业务标签，即维度表中的描述属性。
一致性处理业务度量及性能指标，通常是事实表中的事实。
去除重复数据。
国际化处理。
将一致性处理后的数据保存到数据准备区。
4．交付阶段的主要任务是：
加载星型的和经过雪花处理的维度表数据。
产生日期维度。
加载退化维度。
加载子维度。
加载1、2、3型的缓慢变化维度。
处理迟到的维度和迟到的事实。
加载多值维度。
加载有复杂层级结构的维度。
加载文本事实到维度表。
处理事实表的代理键。
加载三个基本类型的事实表数据。
加载和更新聚集。
将处理好的数据加载到数据仓库。
从这个任务列表中可以看出，ETL的过程和数据仓库建模的过程结合的非常紧密。换句话说，ETL系统的设计应该和目标表的设计同时开始。通常来说，数据仓库架构师和ETL系统设计师是同一个人。

第8题：

The(69)Process Group consists of the processes used to complete the work defined in the project management plan to accomplish the project's requirements．

A．Plannlng

B．Executing

C．Monitoring and Controlling

D．Closing

正确答案：B
解析：执行过程组由用于完成为达成项目要求而在项目管理计划中定义的工作的过程组成。

第9题：

第三组：

The sewage treatment system must be capable of discharging an effluent that comes within the limits of the tests. Sewage can be treated biologically so that it may be discharged with minimal damage to ecosystem. Biological treatment involves the use of living organisms to treat the sewage within the sewage treatment plant so the liquids and sludge discharged are within the standards specified.

Biological treatment plants are usually built up as a module and consist of various sections.

Waste matter collected from the ships sanitary appliances is led through a sanitary piping system to the treatment module. The solid matter is broken up by passing it through a screen or a series of revolving cutters. The broken up solid material, together with the waste liquid, passes into a tank containing bacteria which require oxygen and a nutrient to propagate. The nutrient is contained in the solid waste material, and oxygen is supplied by bubbling compressed air through the broken up waste. The propagated bacteria change the waste material into a sludge by aerobic digestion. The sludge is finally treated to kill the coliform. bacteria before it is passed overboard.

When a biological sewage plant is started up, such as when activating a new ship or after cleaning out the tank, a pellet containing bacteria is introduced into the tank. It takes approximately one week for the bacteria to propagate and make the system fully effective. The choice of sanitary appliance cleaners requires extreme care, as many cleaners are toxic to the active bacteria. Once a biological sewage plant is made active it should not be shut down. If it is it will have to be reactivated again because the bacteria will die without a supply of nutrients and oxygen.

Bacteria that require oxygen for their survival are referred to as aerobic. Aerobic bacteria are normally used in ships&39; sewage treatment equipment. Other forms of bacteria that do not require oxygen are referred to as anaerobic. Anaerobic bacteria are used in shore based sewage treatment works where methane is obtained as a by-product for use as fuel.

This passage is mainly about

A.sewage treatment methods

B.the various sections of a sewage treatment plants

C.biological sewage treatment system

D.how the sewage treatment plants are started up

正确答案：C

第10题：

Most marine biological sewage treatment plants consist of all the following statements except ______.

A.aeration(通风) tanks

B.settling tanks

C.disinfection agent(消毒剂)

D.anaerobic bacteria(厌氧菌)

正确答案：D

The basic process of biological sewage treatment consists of

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