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The function of the piston compression rings used in a diesel engine is to （）
A . seal the space between the piston and liner
B . transmit heat from the piston to the cylinder liner
C . reduce the amount of combustion gas blow-by
D . all of the above
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You are writing a method to compress an array of bytes. The array is passed to the method in a parameter named document. You need to compress the incoming array of bytes and return the result as an array of bytes. Which code segment should you use?（）
A .https://assets.asklib.com/images/image2/2018072715124350961.jpg
B .https://assets.asklib.com/images/image2/2018072715124925568.jpg
C .https://assets.asklib.com/images/image2/2018072715125337253.jpg
D .https://assets.asklib.com/images/image2/2018072715125650375.jpg
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You want to compress your folder named test on a FAT32 file system. When you try to compress the folder， you found no advance tab in the folder’s property window. What may be its reason.（）
A . You are not an administrator
B . A local system policy is implemented to hide the advance tab
C . FAT32 does not support compression
D . Delete and recreate the testing folder
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Which of the following relationships should occur between the temperature developed in a combustion space, and the compression ratio of the engine?（）
A . Higher compression ratios create higher temperature
B . Higher temperatures create higher compression ratios
C . low temperatures create higher compression ratios
D . Higher compression ratios create low temperature
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The needle valve in a fuel valve will （） when the fuel pressure action on the needle valve tapered face exerts a force lower than that of the spring compression.
A . be jammed
B . be opened
C . be seated
D . be broke
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A drop in compression pressure in one cylinder of a diesel engine can be caused by（）
A . a leaking fuel injection nozzle
B . a clogged air filter
C . early fuel injection
D . burned valve
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Low compression pressure in a diesel engine is caused by（）
A . low water in the expansion tank
B . improperly seated valves
C . low fuel oil pressure
D . worn or broken cylinder liner sealing ring
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A sudden drop in diesel engine cylinder compression pressure can be caused by（）
A . a leaking fuel injector nozzle
B . a clogged air filter
C . excessively early fuel injection
D . malfunctioning valve
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The fresh air coming in through the inner air ports, is compressed by（） to a higher pressure.
A . the cylinder head
B . the cross-head
C . the moving piston
D . the stationary pisto
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How are the pressure and temperature affected in a diesel engine cylinder during compression?（）
A . Pressure and temperature decrease
B . Pressure and temperature increase
C . Pressure decreases and temperature increases
D . Pressure increases and temperature decrease
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You are using Recovery Manager (RMAN) to perform backups. In which three situations would you perform a compressed backup?（）
A . You are backing up to tape and your tape device performs its own compression.
B . You are making image copies, and you have not enabled tablespace compression.
C . You are using disk-based backups and disk space in your Flash Recovery Area, or other disk-based backup destinations are limited.
D . You are performing your backups to some device over a network where reduced network bandwidth is more important than CPU usage.
E . You are using some archival backup media, such as CD or DVD, where reducing backup sizes saves media costs and archival storage.
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A sudden drop in compression pressure in one cylinder of a diesel engine can be caused by（）
A . a leaking fuel injector nozzle
B . a clogged air filter
C . excessively early fuel injection
D . malfunctioning valve
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Increasing the compression ratio of a diesel engine while maintaining the designed rate of fuel flow will result in （）
A . increased horsepower
B . reduced efficiency
C . increased heat loss
D . lower cylinder pressure
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Low compression in a diesel engine can be caused by （）
A . clogged coolant passages
B . a leaking cylinder head gasket
C . low fuel oil pressure
D . worn or broken cylinder liner sealing ring
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In the starting process of a diesel engine, the main object is to attain the compression conditions sufficient to （）
A . turn the flywheel
B . reduce friction
C . overcome inertia
D . ignite the fuel
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If the compression rings on a diesel engine piston become stuck in the ring groove, the cause may be due to（）
A . excessive ring action
B . excessive ring temperature
C . improper ring rotation
D . excessive ring face wear
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In a compression refrigeration cycle, the temperature of the liquid refrigerant experiences its greatest decrease in the（）.
A . evaporator
B . compressor
C . expansion valve
D . condenser
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The latent heat of evaporation is dissipated in the （） in a compression refrigeration system.
A . evaporator
B . condenser
C . expansion valve
D . compressor
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Low compression pressure in a diesel engine can be caused by（）
A . improperly seating intake valves
B . leaking cylinder liner seal rings
C . late fuel injection timing
D . carbon deposits on the pisto
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In a vapor compression refrigeration the evaporating pressure is maintained constant by the action of the （）, which removes vapor from the evaporator at the same rate at which it is formed.
A . evaporator
B . compressor
C . condenser
D . none of the above
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Low compression in a diesel engine could be caused by（）
A . worn or broken cylinder liner sealing rings
B . high cooling water temperature
C . worn or broken piston rings
D . low fuel oil pressure
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In the suction stroke air is induced into the cylinder （）In the compression stroke the air is compressed.
A . by an fuel valve
B . through an inlet valve
C . with an exhaust valve
D . from an outlet valve
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Low compression pressure in a diesel engine can be caused by_____________.
A.improperly seating intake valves
B.leaking cylinder liner seal rings
C.late fuel injection timing
D.carbon deposits on the piston
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Low compression pressure in a diesel engine is caused by___________.
A.low water in the expansion tank
B.improperly seated valves
C.low fuel oil pressure
D.worn or broken cylinder liner sealing rings
