乙类适任证书(轮机英语)模拟试题2

主机以83转/分钟正常航行时，增压器的转速为11700转/分钟，上午10时增压器突然开始产生异常声音，出现振动，主机转速降至60转/分钟, 同时增压器转速降至2400转/分钟。

主机废气涡轮增压器需解体、清洁及检查，喷嘴环、压气机和涡轮机端轴承用船上备件换新，所有其它部件发现不合格也全部换新，装复时记录所有装配间隙。

The exciter must vary with: ① load current② the power factor, ③ speed change of the prime mover.

When the load has a lagging power factor this voltage drop is considerable. This sentence means that _____.

材料：

The field current supply in older machines comes from a lower voltage direct current generator or exciter on the same shaft as the alternator. Modern machines however are either statically excited or of the high-speed brush-less type. The exciter is required to operate to counter the effects of power factor for a given load. The power factor is a measure of the phase difference between voltage and current and is expressed as the cosine of the phase angle. With a purely resistance load the voltage and the current are in phase, giving a power factor of one. The power consumed is therefore the product of voltage and current. Inductive or capacitive loads, combined with resistance loads, produce lagging or leading power factors which have a value less than one. 

The power consumed is therefore the product of current, voltage and power factor. The alternating current generator supplying a load has a voltage drop resulting from the load. When the load has a lagging power factor this voltage drop is considerable. Therefore the exciter, in maintaining the alternator voltage, must vary with load current and also the power factor. The speed change of the prime mover must also be taken into account. 

问题： The word “machines” in the passage refers to _____.

Which of the following statements is true according to the passage ?

PSC inspection is implemented by______ through______.

Before exercising PSC, a port state should______.

Who will be responsible for ensuring that a ship maintains a standard at least equivalent to that specified in international conventions?

材料：

Port State Control (PSC) is the inspection of foreign ships in national ports for the purpose of verifying that the condition of the ship and its equipment comply with the requirements of international conventions and that the ship is manned and operated in compliance with applicable international laws. The primary responsibility for ensuring that a ship maintains a standard at least equivalent to that specified in international conventions rests with the flag State and if all flag States performed their duties satisfactorily there would be no need for port State control. Unfortunately this is not the case as evidenced by the many marine accidents around the world - hence the need for additional control.

The authority for exercising PSC is the national law based on relevant conventions. It is therefore necessary for a port State to be Party to those conventions and to have promulgated the necessary legislation before exercising PSC.In accordance with the provisions of the applicable conventions, Parties may conduct inspections of foreign ships in their ports through Port State Control Officers (PSCOs). 

问题：The purpose of PSC is ______.

① to check and inspect foreign ships 

② to verify the condition of a ship in compliance with requirements of international conventions; 

③ to make sure that the ship is manned and operated well; 

④to detain ships