Manufacturing Empire in the Valley

Chapter 32 Master, what is a Bessel function?
Wang Xiaoshuang dropped out of school just like that. According to her classmates who lived in the same village as Wang Xiaoshuang, Wang Xiaoshuang seemed to be a different person after dropping out of school. .

This incident hit Ms. Li a bit hard, and she never showed a smile on her face until the weekend holiday.

At noon on Saturday, after the last class, Niu Xiaoqiang picked up his schoolbag and went home.

Niu Xiaoqiang was not very sorry about the dropout at the same table, because he had seen this kind of thing more than once.Many families will make this kind of forced decision when they are at the end of their means. If you see it a lot, you will naturally get used to it.

"Mom, you rest first, let me cook." Niu Xiaoqiang threw down his schoolbag when he got home, and ran into the kitchen to help his mother with the housework.

Sun Mei smiled very relieved: "Yaowa, you are about to take the final exam, you should go to review your homework, I don't need your help in cooking."

Niu Xiaoqiang snatched the spatula from his mother: "There is no rush to review homework at this time."

Sun Mei couldn't resist, so she nodded in agreement.

After making lunch, Niu Xiaoqiang ran to the field against the scorching sun and called back his father and eldest sister who were working in the field.The four of them sat down at the table and started to eat.

There are only three dishes on the table, one fried beans, one fried water spinach and a plate of sour radish.Niu Xiaoqiang was the first to finish the meal. He put away the bowls and chopsticks, got up and asked his father for advice: "Dad, if there is nothing else to do in the afternoon, I want to go to Grandpa Fang's house for class."

According to the agreement between Fang Dongping and Niu Dazhuang, Niu Xiaoqiang would go to his place for a class every two weeks.Today is exactly half a month since I went to class last time, so Niu Xiaoqiang took the initiative to make this request.

Niu Dazhuang supported the class, he nodded, and said: "Go, remember to study hard, don't mess around, or I will break your leg."

"I know, I will study hard."

After Niu Xiaoqiang finished speaking, he packed up the things he needed for class, and went out with his schoolbag on his back.

At two o'clock in the afternoon, he arrived at the courtyard gate of Fang Dongping's house.

Fang Dongping was sitting under the big tree in the yard drinking some wine.He didn't drink alcohol at first, and his alcohol addiction was acquired when he was sent to Niujia Village.At that time, he was very depressed. Although Niu Dazhuang didn't really criticize him, he still couldn't forget the crazy faces of his students, and he was depressed all day long.It just so happened that every family in Niujia Village could brew Baogu Shao, and under Niu Dazhuang's instigation, Fang Dongping used alcohol to soothe his sorrows, and gradually became addicted to alcohol.

"Master, here I come."

Niu Xiaoqiang greeted Fang Dongping with a smile after walking into the gate.Fang Dongping couldn't help being taken aback, and looked Niu Xiaoqiang up and down: "The night before yesterday, your parents gave me pork and said that you caught the wild boar. I couldn't believe it was true at the time, but now it seems that you really It has become different from before, not only the eyes have become a lot more spiritual, but also the speech is not tied up."

Niu Xiaoqiang didn't want to bother to explain how he became smart, he laughed and said, "It's really nothing, Master, what are we going to talk about today?"

Fang Dongping pointed to a few bearings on the table with his chopsticks: "It's still the same today. The first thing is to learn to look for and find the defects on the bearings. This is a manual course, and then there is a cultural theory class."

Niu Xiaoqiang snorted, hung his schoolbag on the branch of a tree, walked to the basin to wash his hands, and then turned around to find out the problems with these bearings.

These days, domestic fitters are very good. Just relying on the feel, they can check whether there is any problem with the bearing, such as whether there is a very small crack, or the smoothness is not up to standard, etc.

Bearings are precision components, and every machine tool has them. If you want to control the machine tool well, you can't do it without learning how to check it.

Niu Xiaoqiang wiped his hands clean, then erected a bearing, stroked his fingertips back and forth on the bearing, and observed carefully with his eyes while touching him.

Although Niu Xiaoqiang used to be an idiot, he had accumulated some experience in manual operations, but he was not satisfactory in cultural lessons.Relying on his subtle observation and feel, he quickly found that the smoothness of this bearing was not high enough, and there were two places where it was slightly rough.

Regardless of such a small problem, if it is not corrected, it will accelerate the wear of the bearing, or cause metal fatigue, and even serious production accidents such as broken shafts in severe cases.

After Niu Xiaoqiang pointed out the shortcomings he found, Fang Dongping nodded with a smile: "Well, let's check the next one."

In the next 10 minutes, Niu Xiaoqiang checked all the remaining bearings and found [-] problems in total.

Fang Dongping was very satisfied with this, he drank the last sip of wine in the glass, got up and walked to the table, and the old and the young started teaching cultural theory courses in this simple courtyard.

In the past, Fang Dongping always talked on his own in cultural classes. Although he knew that Niu Xiaoqiang would not be able to understand, he still spoke with great enthusiasm.Because it makes him feel like going back in time and teaching students in university lecture halls.

Today was different, Fang Dongping had just written an equation on a simple wooden board, Niu Xiaoqiang took the initiative to ask: "Master, what did you write?"

Fang Dongping was stunned for a moment, and then remembered that the student in front of him was no longer the fool he was before. He smiled happily and explained: "This is a Bessel function equation."

"Master, what is a Bessel function equation?"

"If you want to understand this problem, you must first understand what a Bessel function is."

"Master, can you explain it to me in detail?"

Fang Dongping couldn't wait for this, he nodded with a smile: "Of course there is no problem, Bessel function is a general term for a certain type of special function, and if no specific conditions are specified, the general Bessel function will use the following expressed by this ordinary differential equation.”

After he finished speaking, he picked up the pen and scribbled down an equation in Niu Xiaoqiang's notebook, and then continued: "This is a second-order ordinary differential equation——"

"Master, what does the second order mean?"

When Fang Dongping heard this question, he didn't rush to answer, but smiled wryly: "Xiaoqiang, why don't we start with junior high school mathematics, otherwise you don't understand what I'm talking about at all, but I don't have relevant teaching here. The textbooks are not very easy to handle..."

Niu Xiaoqiang had thought of this a long time ago, and with a grin, he took out the math textbook used by his fourth sister Niu Dongxiang from his schoolbag, and put it in front of Fang Dongping: "Master, I have already prepared it. "

　Please collect, ask for recommendation tickets, Weiyu smiled and implored everyone to support, thank you!
　　


(End of this chapter)