问题 问答题 简答题

10kV配电线路为什么只装过流不装速断保护?

答案

参考答案:

10kV配电线供电距离较短,线路首端和末端短路电流值相差不大,速断保护按躲过线路末端短路电流整定,保护范围太小;

另外过流保护动作时间较短,当具备这两种情况时就不必装电流速断保护。

阅读理解

阅读理解。

     Diving around Halaveli Island was a really unforgettable experience. I participated (参加) in a day

diving trip that had lunch on the boat. We went to Maalhoss Thila first. The current (水流) can be very

strong here but we were lucky and had a mild one. We enjoyed all the different colors of coral and fish.

The maximum (最大) depth of this dive was 30m, and we stayed for about 40 minutes. The water was

reasonably warm, so I was not cold only wearing a short-sleeved (袖子) wetsuit.

     I was a bit worried about having lunch on the boat, as sometimes my stomach feels bad, but it was

perfectly fine this time -perhaps because the boat had not stopped and was moving toward the other

dive place, or because the size of the boat was reasonably large.

     Our next diving place was called Manta. And as expected, the huge Manta was soon around us. It

is one of the most exciting moments I have had in my life. We only dove to 14m this time, which allowed

us to stay a bit longer -almost 50 minutes.

     On the way back all the women took strategic position (好位置) on the deck, sunbathing and

relaxing, while the men were getting bored and ate the leftovers from lunch. No matter how different we

were, we all enjoyed our trip.

     Another dive I would like to recommend (推荐) is called Maaya Thila, and it is the best night dive I

have ever had. We saw a huge turtle (海龟) sleeping in a cave, and sharks (鲨鱼) playfully chasing (追

赶) each other. They did not look friendly at all, but fortunately they did not decided to have us for

dinner. But anyway what happened that night under water will remain a fond memory to be retold on

special occasions by all the participants (参加者). It will be told with a smile on our faces.

1. What information can we get from the passage?  

A. The author enjoyed different colors of fish in Manta.

B. Diving in Maaya Thila is one of the most unforgettable experience for the author.

C. The author dove into Maaya Thila and stayed there for 50 minutes.

D. There were no dangerous sharks in Maaya Thila.

2. The author was worried about having lunch on the boat because ______.

A. the boat was not stopped

B. it was moving toward the other dive place

C. the boat was not big enough

D. he / she felt sick when eating on boats

3. How many diving places are mentioned in the passage?   

A. 1.    

B. 2.    

C. 3.    

D. 4.

4. We learn from the last paragraph that ________.    

A. Maaya Thila was only suitable for a night dive

B. many people had been killed at Maaya Thila

C. Maaya Thila is popular among all the participants

D. few people have the courage to dive at Maaya Thila

5. The author wrote this passage to ________.

A. share some wonderful experiences of diving with readers

B. make an attractive advertisement for a famous park

C. give you some tips when you go out for a dive

D. tell the readers how to spend a weekend or a long holiday

填空题

阅读以下说明和算法,完善算法并回答问题,将解答写在对应栏内。
[说明]
假设以二维数组G[1..m,1..n]表示一幅图像各像素的颜色,则G[i,j]表示区域中点(i,j]处的颜色,颜色值为0到k的整数。
下面的算法将指定点(i0,j0)所在的同色邻接区域的颜色置换为给定的颜色值。约定所有与点(i0,j0)同色的上、下、左、右可连通的点组成同色邻接区域。
例如,一幅8×9像素的图像如图1-1所示。设用户指定点(3,5),其颜色值为0,此时其上方(2,5)、下方(4,5)、右方(3,6)邻接点的颜色值都为0,因此这些点属于点(3,5)所在的同色邻接区域,再从上、下、左、右四个方向进行扩展,可得出该同色邻接区域的其他点(见图1-1中的阴影部分)。将上述同色区域的颜色替换为颜色值7所得的新图像如图1-2所示。


[算法]
输入:矩阵G,点的坐标(i0,j0),新颜色值newcolor。
输出:点(i0,j0)所在同色邻接区域的颜色置换为newcolor之后的矩阵G。
算法步骤(为规范算法,规定该算法只在第七步后结束):
第一步:若点(i0,j0)的颜色值与新颜色值newcolor相同,则 (1)
第二步:点(i0,j0)的颜色值→oldcolor;创建栈S,并将点坐标(i0,j0)入栈;
第三步:若 (2) ,则转第七步;
第四步:栈顶元素出栈→(x,y),并 (3)
第五步:
1) 若点(x,y-1)在图像中且G[x,y-1]等于oldcolor,则(x,y-1)入栈S;
2) 若点(x,y+1)在图像中且G[x,y+1]等于oldcolor,则(x,y+1)入栈S;
3) 若点(x-1,y)在图像中且G[x-1,y]等于oldcolor,则(x-1,y)入栈S;
4) 若点(x+1,y)在图像中且G[x+1,y)等于oldcolor,则(x+1,y)入栈S:
第六步:转 (4)
第七步:算法结束。
[问题]
是否可以将算法中的栈换成队列回答: (5)