【判断题】在9阶B-树中,除叶子以外的任意结点的分支数介于5和9之间。
【单选题】从家电、住房到汽车消费,很长一段时间,我国居民消费需求呈现出明显的模仿型排浪式特征,消费热点比较集中。目前,模仿型排浪式消费阶段基本结束,个性化、多样化消费渐成主流。这意味着() ①求异消费将成为人们的主导消费模式 ②通过创新供给激活需求显得更为重要 ③民众消费受到预期收入影响越来越小 ④新的产品、业态和服务将会不断涌现
【单选题】Telescopic pipes to the piston of a large slow-speed main propulsion diesel engine are designed to prevent _____.
A.
excessive crankcase pressure
B.
excessive lube oil temperature
C.
contamination of the lube oil by water
D.
contamination of the cooling water by lube oil
【单选题】Which of the following procedures should be carried out when a large, low-speed, diesel engine is operated with one cylinder secured? .
A.
Lubrication to the defective cylinder should be increased
B.
Cooling water temperature to the engine should be increased
C.
Only the turbocharger speed should be reduced
D.
Engine speed should be reduced
【单选题】The slow speed main propulsion diesel usually operates on ___________ .
【单选题】The power developed by a large slow-speed main propulsion diesel engine is dependent upon the _______.
A.
quantity of air it takes in and retains in the cylinders during a given time period
B.
proportion of trapped air that is utilized in the combustion process
C.
thermodynamic efficiency of the engine cycle
【单选题】下列哪一种表现,一般不属于实证的病理反映( )
【单选题】The slow speed main propulsion diesel usully operates on ____.