问题 问答题 简答题

简述ABS防抱死制动系统的组成及其工作过程。

答案

参考答案:

组成:轮速传感器、电子控制器、液压调节器

工作过程:轮速传感器将车轮转速信号传给电子控制器,由此计算出车轮滑移率并以此为依据控制各轮缸油压,最终使车轮滑移率总保持在8%-35%范围内,使车轮保持较高的纵向和侧向附着力。

判断题
单项选择题

It’s a typical Snoopy card: cheerful message, bright colors, though a little yellow and faded now. Though I’ve received fancier, more expensive cards over the years, this is the only one I’ve saved. One summer, it spoke volumes to me.
I received it during the first June I faced as a widow to raise two teenage daughters alone. In all the emotional confusion of this sudden single parent- hood, I was overwhelmed with, of all things, the simplest housework: leaky taps, oil’ changes, even barbecues (烧烤). Those had always been my husband’s jobs. I was embarrassed every time I hit my thumb with a hammer or couldn’t get the lawnmower (割草机) started. My uncertain at- tempts only fueled the fear inside me: How could I be both a father and mother to my girls Clearly, I lacked the tools and skills.
On this particular morning, my girls pushed me into the living room to see something. (I prayed it wasn’t another repair job). The "something" turned out to be an envelope and several wrapped bundles on the carpet. My puzzlement must have been plain as I gazed from the colorful packages to my daughters’ bright faces.
"Go ahead! Open them!" they urged. As I unwrapped the packages, I discovered a small barbecue grill (烧烤架) and all the necessary objects in- eluding a green kitchen glove with a frog pattern on it.
"But why" I asked.
"Happy Father’s Day!" they shouted together.
"Moms don’t get presents on Father’s Day," I protested.
"You forgot to open the card," Jane reminded. I pulled it from the envelope. There sat Snoopy, on top of his dog house, merrily wishing me a Happy Father’s Day. "Because," the girls said, "you’ve been a father and mother to us. Why shouldn’t you be remembered on Father’s Day"
As I fought back tears, I realized they were right. I wanted to be a "professional" dad, who had the latest tools and knew all the tricks of the trade. The girls only wanted a parent they could count on to be there, day after day, performing repeatedly the maintenance tasks of basic care and love.
The girls are grown now, and they still send me Father’s Day cards, but none of those cards means as much to me as that first one. Its simple message told me being a great parent didn’t require any special tools at all--just a willing worker.

By "it spoke volumes to me" (Para. 1), the mother in the story means the card ______.

A. conveyed significant meanings to her
B. aroused great sorrow in her
C. brought her pleasant feelings
D. made her feel, important