[单项选择]In order to improve the efficiency of the communication with shore personnel, you should（）
A. inform the chief engineer whenever there are problems
B. reduce the time wasted on checking items
C. know who is responsible for the domestic cleaning equipment
D. know the chain of authority on the ship

[单项选择]In order to improve the working conditions of the crosshead bearings, the bearing pressure is made and the peripheral speed is made in later designs（）
A. smaller, higher
B. higher, smaller
C. smaller, smaller
D. higher, higher

[多项选择]Why does the data communication industry use the layered OSI reference model? (Choose two.)（）
A. It divides the network communication process into smaller and simpler components， thus aiding component development， design， and troubleshooting.
B. It enables equipment from different vendors to use the same electronic components， thus saving research and development funds.
C. It supports the evolution of multiple competing standards， and thus provides business opportunities for equipment manufacturers.
D. It encourages industry standardization by defining what functions occur at each layer of the model.
E. It provides a means by which changes in functionality in one layer require changes in other layers.

[单项选择]The efficiency of turbocharge system is increased by fitting a charge air cooler （） the compressor.
A. inside
B. before
C. after
D. against

[单项选择]The conclusion that mechanical efficiency is always （） 100 percent is correct.
A. small than
B. more than
C. little than
D. less than

[单项选择]The mechanical efficiency of an engine is always less than 100% （） losses occurring in the form friction.
A. because
B. since
C. due to
D. owing to

[单项选择]The mechanical efficiency of an engine （） because losses occur in the form of friction.
A. is always less than 100%
B. is always more than 100%
C. is always equal to 90%
D. is always less than 90%

[单项选择]Increased air （） will raise scavenge efficiency and allow a greater mass of air to be compressed； more fuel may now be burned giving an increased power.
A. specific volume
B. density
C. viscosity
D. calorific value

[单项选择]To obtain maximum efficiency, two stage air compressors are usually （）.
A. horizontally mounted
B. never fitted with intake filters
C. fitted with intercoolers
D. operated in an unloaded condition at all times

[单项选择]The efficiency and output capacity of a low pressure distilling plant will be reduced if the last effect shell （）
A. pressure does not fluctuate rapidly
B. pressure remains steady and unchanged
C. brine density does not exceed 1~5
D. brine density is too low

[单项选择]What happens to the efficiency of an anchor when it is moved from sand to mud?（）
A. The efficiency increases
B. The efficiency decreases
C. The efficiency remains the same
D. The efficiency cannot be determined.

[单项选择]The efficiency of a flash type evaporator can be increased by（）
A. lowering brine discharge density
B. decreasing the absolute pressure of each stage
C. increasing the saltwater feed heater temperature
D. increasing the pressure at the spray pipe

[单项选择]The following measures can be used to improve oily water separator’s separating effect except （）
A. overhauling every two year
B. working at intervals
C. renewing filtration material
D. pumping bilge water from different layers respectively

[单项选择]The act of speaking will also help to improve listening comprehension（）
A. to some way
B. in the way
C. to some extent
D. in the extent

[单项选择]You may improve a vessels stability by （）.
A. keeping the fuel tanks topped off
B. increasing the free surface effect
C. keeping the fuel tanks at least half MI
D. keeping at least one fuel tank empty for slops

[单项选择]An additive used to improve the ability of a lube oil to reduce friction is known as a/an （）.
A. suppressant additive
B. dispersant additive
C. extreme pressure additive
D. viscosity improver additive

[单项选择]To improve your vessel’s stability in a hazardous situation，you should（）.
A. ballast deep tanks if they are slack
B. transfer ballast athwartships
C. pump out double bottoms
D. fill double bottoms from deep tanks

[单项选择]To improve your vessel’s stabilty in a hazardous situation, you should（）.
A. ballast deep tanks if they are slack
B. transfer ballast athwarships
C. pump out double bottoms
D. fill double bottom from deep tanks

[单项选择]If separating effect is not good, we can improve it by （）
A. flushing separator with hot water
B. increasing water supply flow
C. heat oily water properly
D. opening manual oil discharge value

[简答题]Man was, is and always will be trying to improve his living conditions.