"The extreme value principle plays a very important role in the study of partial differential equations. Based on the above reasons, I have summarized several extreme value principles of partial differential equations, and also given several applications of several extreme value principles." Department of Mathematics

In the conference room, a senior student was nervously explaining the outline of his thesis.

As the number one department in the country, the Mathematics Department of Capital University is not like those schools where you can graduate just by paying the money. It is quite strict about graduation thesis cards; for those who have low quality and problems with the logical sequence,

Papers that cite insufficiently authoritative materials are usually not easily passed, so in addition to the student who is defending, others are also looking at their papers nervously; only Lu Qiujian still looks relaxed

Look.

Professor Nan also returned to Beijing Normal University this semester. Now he is sitting on the stage and listening carefully to the student's report. After he finished the report, he moved the microphone to his mouth and asked, "Tell me about your experience in the energy model."

Estimate the reason why that formula is used in the fifth subsection of that section. Is this formula the best choice for this problem?"

"Well, that's what I thought about it." The students below could clearly hear his voice trembling, and they themselves became nervous. The Professor Nan in front of him originally gave the students seven major mathematical problems as questions for the final exam.

!The requirements for graduation thesis will only be higher!

Why didn't he come back half a semester late? We have never attended his class and still have to be assessed by him. What a big loss! Everyone murmured in their hearts.

"It's inappropriate for you to put this formula here. You didn't consider the problem of sum that still needs to be solved, and you didn't make up for this loophole in the subsequent article!" As soon as he finished answering, Professor Nan shook his head and said politely.

Pointed out the errors, "So, your paper has major flaws! I suggest"

"Ahem, Professor Nan!" Professor Zhang couldn't help but interrupt him. Although there are certain problems with this paper, they are not irreversible. Don't just shoot this kid to death!"

I think it’s better to let him go back and revise it and then defend it again!”

"Well, that's it!" Professor Nan hesitated for a moment and agreed with Professor Zhang's opinion.

"Thank you, Professor Zhang, thank you, Professor Nan. Thank you, Professor Ren." The child was so aggrieved that he almost cried, and he had to bow to express his thanks in a polite manner.

There is such an example before. The students who defended next became more nervous; but the more nervous they are, the more likely they are to make mistakes. Some originally had no problems with their papers, but when Professor Nan asked them, they became confused. The words that came out of their mouths

If he failed to achieve his goals, he soon suffered a similar fate as the classmate just now.

Lu Qiujian's roommates, Xu Ye and Li Yincheng, were better. They had already asked Lu Qiujian to read their thesis for them, and all the obvious problems were solved, so they passed this test and successfully passed the defense.

"Kong Yuan, please come forward for the defense, and Lu Qiujian, please be ready!" The time for the defense passed quickly, and soon Lun arrived at Lu Qiujian. He took out the paper from the document bag and prepared the defense.

preparation.

"Yes. You answered several questions quite well. I can see that you have done a good job in preparation!" Professor Nan said after hearing Kong Yuan's answers, "There are just a few details that are not handled perfectly.

I’ll let you pass the first defense; but if you want to publish it, I’m afraid you need to make more improvements.”

"Yes, thank you Professor Nan, thank you Professor Zhang." Kong Yuan let out a big sigh of relief and bowed to express his thanks one by one while holding back his laughter.

Next it was Lu Qiujian's turn, and almost everyone in the conference room turned their attention to him. In the conference room next door, people from other classes who had finished their defense also sneaked in. They wanted to see what this legendary figure from the Capital University was doing in their thesis.

How elegant he was during his defense.

"Haha, Xiao Lu. You have been staying at the Institute of High Energy for several months! You didn't even visit Professor Nan much after he returned to China. This is a bit inappropriate!" Before Lu Qiujian could start to elaborate on his thesis,

, Professor Zhang said with a smile, if Lu Qiujian hadn’t published more papers during this period, he would have gone to the Institute of High Energy to find him out!

"Yes, this is my fault! I will definitely apologize to Professor Nan later!" After Professor Nan returned to China, he only met him once at the welcome party on the first day, and he has been staying at the Institute of High Energy since then, which is a bit embarrassing.

Not kind.

"It's okay, you can see me anytime you want. Such learning opportunities don't come around all the time; besides, your recent articles have given me a lot of inspiration!" Professor Nan changed his previous harshness and said generously.

meaning.

"Are you used to being in a high-energy place? If you ask me, the canteen there is really outrageous. The last time I went there, the braised pork was so overcooked that every bite was oily. It was a waste of good pork belly!

Professor Zhang grinned as he spoke, as if there really was such a piece of braised pork in his mouth.

"Comparing this to universities and research institutes across the country, the braised pork in the staff cafeteria of Tancheng University is the best! It's really sweet, soft, fat but not greasy." Professor Ren, who had not asked many questions just now

I also became interested and joined in their conversation.

Lu Qiujian and the students in the audience were all confused. Teacher, this is the defense of the Mathematics Department of Capital University, not the graduation project assessment of New East Culinary School!

"Of course, it doesn't matter where Tancheng is! The braised pork comes from them!" Another professor spoke up, "I have to look at universities across the country several times, but no one can compare to the braised pork.

Their good!”

"I have no objection if you just say it's braised pork! But I don't agree if you expand the scope to include meat!" Someone immediately stood up to object, "Dongpo pork from the Academic Exchange Center of Wuyue University! Gu from the expert cafeteria of Guangdong University

Delicious meat! And the roasted pork from the Institute of Religion of Shuzhong University! That one is not inferior to him! I’m just talking about pork, and I haven’t mentioned the yak meat from Tubo University, the hand-caught mutton from Western Region University and the Baodao University.”

This person is obviously a food expert, and everyone here couldn't help but swallow his saliva when he spoke. Seeing that the topic was getting a little far, Professor Ren quickly patted the table, "Everyone, I want to eat meat for a while, so I'll treat you. Why don't we do it now?"

The defense is here!"

At this time, everyone woke up from the lively discussion. Professor Zhao smiled sheepishly, and then looked at Professor Nan, "Professor Nan, it's almost time for you to watch the defense. Let's go straight to Xiao Lu, right?"

"Well, let's live it then!" The students in the audience were once again in a state of confusion! (~^~)

ps: Well, I can go abroad in the next chapter. Thanks to the 588 reward from the Second Emperor, thanks to Eclair Falon, Pegasus Spring and Autumn, The Winged Devil's Vest, Book Friends 110614200135495, Feilian Messenger, Big Cat Cat's Eye, Xuanyuan

Chang Lei, the sun and moon shine together, follow the wind jony

100, four Coke bottles, inflation, I am a book friend, Brother Qiang,~. I will give you a reward.
Chapter completed!