In the common rail system, excessive pressure in the header may be caused by （）
A . improper adjustment of the bypass valve
B . a dribble in the fuel injection nozzle
C . insufficient leak-off through injection nozzle packing
D . a malfunctioning injection nozzle
相似题目
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A common rail engine has only one or two high pressure pumps in operation at the same（）time, and the injection into each cylinder.
A . can’t be controlled very precisely
B . can’t be controlled as flexibly as the separate pump system
C . can be controlled as flexibly as the separate pump system
D . can be controlled more precisely and flexibly
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When a system has both online transaction processing as well as large batch processing， which of the following common procedures will best help to improve system performance？（）
A . Boost the priority of batch jobs.
B . Schedule batch runs to reduce contention with OLTP.
C . Schedule OS maintenance such that it includes frequent application of PTFs.
D . Perform incremental backups of transaction processing and full backups of batch processing.
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The most common diesel engine fuel system problems are caused by （）.
A . incorrect adjustments
B . dirty fuel
C . broken fuel lines
D . excessive vibratio
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Hydraulic pumps most commonly used in steering systems are of the （）.
A . lobe type
B . screw type
C . axial piston type
D . volute type
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In a common rail engine, the fuel is injected into cylinders（）
A . by injection pumps
B . at a time decided by the injection pump timing
C . by a signal opening the magnetic valves
D . at a time decided by the cam directly
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What is commonly used to create turbulence in a diesel engine combustion system?（）
A . Shape of the piston crowns
B . Increasing the compression ratios
C . Increasing the piston crowns
D . Increasing the turbocharger gear ratio
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The two most common gases used in pneumatic system are （）
A、compressed air and nitrogen
B、helium and nitrogen.
C、oxygen and hydrogen
D、oxygen and acetylene
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Considering the general circulation of the atmosphere，the wind system between latitudes 30°N and 60°N is commonly called the（）.
A . prevailing westerlies
B . horse latitudes
C . trade winds
D . subpolar low pressure belt
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Cones are more common at the ______ of the eye whereas rods are more common in the ________.
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In the common mode,
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Property law is the area of law that governs the various forms of ownership and ( ) in real property (land as distinct from personal or movable possessions) and in personal property, within the common law legal system.
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What do countries mentioned in the course have in common in celebrating Boxing Day?
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Which one is not the common value in both cultures?
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The following are the common machines in a business center EXCEPT:
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The “Show” gesture is the most common gesture we use in our speech.
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Things impossible in the past are quite common today（）
A．considering
B．having considered
C．to be considered
D．considered
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CIM Rules apply to a contract of carriage by rail if the place of taking incharge of goods and the designated place of delivery are situated in （）.
A、two different states
B、two different customss
C、two same states
D、two different ports
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Why isn’t the word“ sir” commonly used in Britain？
<img src='https://img2.soutiyun.com/ask/uploadfile/2664001-2667000/0b24518b4123fdccbad600fac2ee2f95.gif' />
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The House of Commons in the UK consists of______ members.
A．651
B．535
C．635
D．50
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INTERNATIONAL TRANSPORTATION Transportation plays an important part in international business because goods produced have to be delivered to the buyers abroad, and the delivery of goods is to be made possible by transportayion services. Goods are carried by several means of transportation - on road or rail, by sea or air.And in recent years,combined transportation which is a road-sea-rail carriage has appeared. With the expansion of international trade, the container service has become popular. The use of containers provides a highly effective form. of transportation by road, rail and sea. Basically, about 98% of world trade is carried out by sea transportation.Besides transportation by sea, road, or rail, nowadays in order to speed up delivery, carriage by air has also become popular.
1. Transportation plays an important part in international business because goods produced have to be sent to everywhere in the world.()
2. Usually goods are carried by many ways of transportation.()
3. In recent years, combined transportation which is a road-sea-rail carriage appeared.()
4. With the expansion of international trade, the container service has become popular.()
5. The use of containers gives a very helpful method of transportation by air.()
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In computing, passwords are commonly used to limit access to official users. Yet the widespread use of passwords has serious drawbacks. Office workers now have to remember an average of twelve system passwords. In theory they should use different passwords for each site, but in reality these would be impossible to remember, so many people use the same password for all.
An additional problem is that the majority use simple words such as "hello", or names of family members, instead of more secure combinations of numbers and letters, such as 6ANV76Y. This permits computer hackers to download dictionaries and quickly find the word that allows them access.
When system users forget their passwords there is extra expense in supplying new ones, while if people are forced to change passwords frequently they often write them down, making systems even less secure. Therefore, it is clear that the idea of passwords, which have been used as security devices for thousands of years, may need rethinking.
One possible alternative has been developed by the American firm Real User, and is called "passfaces". In order to access the system a worker has to select a series of photographs of faces from a randomly (随机地) generated sequence. If the pictures are selected in the correct order, access is granted. This concept depends on the human ability to recognize and remember a huge number of different faces, and the advantage is that such a sequence cannot be told to anyone or written down, so is more secure. It is claimed that the picture sequence, which used photographs of university students, is easier to remember than passwords, and it has now been adopted for the United States Senate.
What is the disadvantage of passwords as mentioned in Paragraph 1？
A．They do not ensure security.
B．They are difficult to remember.
C．They have to be changed frequently.
D．They limit computer accessibility.
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common laws are laws which have been established through common practice in the courts. ()
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You have left out （)“m”in the word "common” .
A．a
B．an
C．/
D．the
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In Britain, Parliament consists of the House of Lords, the House of Commons, and
A．the Labour Party
B．the Prime Minister
C．the Lord Chancellor
D．the Monarch
