Chapter 369: Brother Yang, please fulfill your military training promise

Early morning.

Xu Qingzhou and Song Yao had both been busy for many days. Finally resting, they slept until 10 o'clock.

They ate something casually at noon. Before 1 o'clock, Song Yao changed her clothes and prepared to go out. Resting for two days, she had an appointment with Ding Jiahui to go shopping.

Still a "sisters' game."

Guo Ziyang was busy with a new project.

Xu Qingzhou was also free and prepared to catch up on sleep.

"I'm going out. Is there anything you want to buy?"

"No."

Xu Qingzhou lay on the sofa with his limbs spread out. After eating, he started to feel sleepy just after sitting for a while.

"Cover yourself with the blanket, don't catch a cold."

Song Yao reminded.

"Got it." Xu Qingzhou pulled the blanket from the side and covered himself.

On this side, Er Miao jumped down from the radiator, stretched, and then meowed as it went to Xu Qingzhou's side, nimbly crawling under the blanket, revealing only its head.

Song Yao changed her shoes and looked at the two "wastes," one big and one small, squinting in the living room, and shook her head. What would these two do without her?

Mall entrance.

Ding Jiahui waved. After Song Yao came over, she immediately took her arm and suggested: "Let's shop for a while first, and buy a cup of milk tea when we're tired."

"Yeah, okay."

The two strolled around the mall and soon walked into a knitwear shop.

"I want to buy a pair of gloves for Xu Qingzhou."

Ding Jiahui looked at Song Yao, who was focused on picking gloves: "Yaoyao, I found that you've really changed."

"Hmm?" Song Yao turned her head in confusion.

Ding Jiahui touched her chin and commented: "The 'wife' temperament is getting stronger and stronger."

"..."

"If it were three years ago, I would never have imagined that the cold Yaoyao would actually pick things for a man."

"I couldn't imagine it either..."

Song Yao pursed her lips, thinking of her past self, then thinking of the present, the corners of her mouth curved.

Ding Jiahui laughed and took Song Yao's arm: "However, I just like the current you. People, after all, should smile more, especially you. When you smile, even I am moved. Hehe, why don't you consider it, how about the two of us as a pair?"

"You don't want Guo Ziyang anymore?"

"That's simple, let him be a pair with Xu Qingzhou."

"..."

Yandong Garden.

Achoo~

Xu Qingzhou touched his nose, his expression strange: "The heating at home is quite sufficient, but why does it feel a bit cold?"

After shopping for half a day, the two girls sat down in a milk tea shop.

"Time passes so fast. It feels like we just graduated from high school, and college is almost over."

Ding Jiahui propped her chin and sighed: "I originally wanted to learn from you, but... thinking about it later, forget it. Every family has its own difficult scriptures to recite. Uh, it's the same between couples; our situations are different."

"You can also talk about it."

"How does that saying go? Oh, men are boys until they die. Guo Ziyang is like this; sometimes he's incredibly childish and always makes people angry."

"Your Xu Qingzhou, um, is quite mature, not like Guo Ziyang."

"Is that so..."

Song Yao felt a bit lacking in confidence.

Xu Qingzhou was also very childish, liking to court death for no reason. Hmph, he even said she had an idol burden; clearly, this guy was the one, serious in the eyes of others, but just a pervert.

Ding Jiahui bit the straw, thought for a while, and then laughed out loud.

"Maybe this is the reason I like him. Silly. When he first pursued me, it was raining, and he ran to buy an umbrella in the rain, getting soaked like a drowned rat... But, I think it's so handsome."

"I suspect you're here to show off your affection to me." Song Yao said.

"Cough~ Can't help it. One's own boyfriend, of course, needs to be praised more."

Ding Jiahui lowered her voice, looked around, and only said after seeing that they were relatively far from the crowd: "Also, I found that Guo Ziyang has a perverted hobby."

Song Yao stiffened while drinking milk tea, very sensitive to the word "perverted": "What's wrong with him?"

"He seems to like my hands very much,"

Ding Jiahui spread her fingers and looked at them against the sunlight: "They are indeed very good-looking, but still, it looks a bit perverted."

"It's okay..."

Song Yao's gaze drifted elsewhere, feeling even more guilty.

Is it perverted to like hands?

Xu Qingzhou not only likes hands, but also feet, and all kinds of strange...

Compared to this, it's completely hopeless.

As for her...

When the two are on the sofa, she now always likes to stuff her feet into Xu Qingzhou's arms.

Also very perverted.

Going to die.

It must be influenced by Xu Qingzhou.

Or rather, she fell into this guy's big trap again, boiling a frog in warm water.

First set her up, live together, then to the sofa, then to the bathroom...

Xu Qingzhou wove a big net, and she just fell into the trap like this.

"Haha, actually it's just talk, no problem."

Ding Jiahui rounded it off herself and laughed: "It's normal for a boyfriend to like you and want to be close to you and hold your hand. Eh~ Yaoyao, what's wrong with you?"

"Nothing."

Song Yao shook her head, the more she thought, the angrier she got.

Consequently, in the evening, Xu Qingzhou, who was lying on the sofa leisurely reading a book, was pulled and ravaged by Song Yao.

Mid-December, the sun had already come out, but there was a hint of chill in the air.

Xu Qingzhou and Song Yao had just separated, and on the way to the library, he received a call from Ji Yunshi.

The voice of Ji Yunshi, full of energy, came from the phone: "Student Xu Qingzhou, it's almost 2017. The school has sufficient budget. Do you have any projects you want to declare?"

"Currently... no other ideas."

Xu Qingzhou said helplessly.

"Doesn't matter, doesn't matter. You, if you have ideas, just come directly to me. Funds, experimental equipment, none of it is a problem."

"Okay, thank you, Director." Xu Qingzhou thanked him.

The two exchanged simple pleasantries and hung up the phone.

Xu Qingzhou smiled again. Old Ji was still as enthusiastic as before, but there was no need to be so anxious. Physics would definitely be one of his main directions in the future, and there would be plenty of opportunities later.

He went straight to the library and found an empty seat.

He took out the calculation manuscript of the local smoothing conjecture. After grinding for two days, the second scheme still couldn't be solved, so he planned to take one last look.

At the same time, Ji Yunshi hung up the phone and just arrived at the entrance of the Physics School when he met an acquaintance.

The middle-aged man greeted: "Director Ji, you're quite early today."

"Old Guan, early. Coming early to organize some documents."

"This weather is getting colder and colder. I feel it's colder than last year."

"Yeah, last year was better."

After chatting for a bit, Professor Guan got to the point: "Old Ji, then that project of my student..."

"Old Guan, wait a bit longer. In the new year, the budget of our school hasn't been determined yet."

Ji Yunshi said with a smile.

"Didn't you just say the school budget was sufficient?"

"Did I?"

Ji Yunshi showed an expression of serious recollection, then continued: "You mean my call with Xu Qingzhou just now? I didn't do that on purpose to keep talent for our Physics School... How about this, if there are funds later, I will definitely prioritize your side."

Ji Yunshi said all sorts of things and finally got rid of Professor Guan, sighing to himself: Old Guan, don't you know what level your student is at?

All the funds were squandered, and the results? Hi, zero.

Can't give any funds at all, okay? 8:30 AM.

In the office of the School of Economics, Li Daiyue was checking the work progress with Professor Ke Chen.

Li Daiyue stared at the progress table and said in a deep voice: "Well, if there are no accidents, the project can be concluded in January."

"Yeah, it's not in vain that everyone has been rushing the progress day and night during this period." Professor Ke Chen also said.

"What about the ARIMA model side?"

"I just discussed it with Student Xu Qingzhou yesterday. He said he is confident in controlling the error around 1.5%."

Professor Ke Chen said with a smile.

"This kid is quite confident."

Li Daiyue certainly didn't question Xu Qingzhou's math level. Someone who could solve several world-class math problems was definitely a one-in-a-million genius.

But there is a specialty in the art industry; Xu Qingzhou must be participating in an economics project for the first time.

【In one look...】

Moreover, many top teams cooperated to create models with this value, but Xu Qingzhou was just one person.

Professor Ke Chen smiled: "Let's just wait and see. He means that a complete model can be seen within a week."

Li Daiyue nodded slightly. A 1.5% error was only in a relatively perfect state.

A bit higher was also acceptable.

Li Daiyue considered problems very comprehensively and had even thought about what to do if Xu Qingzhou's final model was unqualified.

Little Yao's boyfriend, that could also be considered her half-disciple. If there really was a problem, she would just sell her old face and find Professor Wang, who was busy, to patch it up.

Not a big problem.

Library.

Xu Qingzhou sighed helplessly, took out a brand-new manuscript, and planned to try the third calculation method.

Because the support of function r regarding variable e is contained within λ, and the phase function satisfies the non-degeneracy property. Therefore, it can be deduced here that for a fixed 【value】, there exist at most ≈λ^e isomorphic sets intersecting with it.

The third scheme had been brewing in Xu Qingzhou's mind for a long time, so he started writing directly.

Therefore, starting over requires returning to the proof of (10.13), which is to say, in the sense of a negligible term, one only needs to prove the following inequality.

Xu Qingzhou narrowed his eyes, his gaze fell on one of the manuscripts, and he used his pen to circle the inequality inside.

It seems...

There's a chance.

Xu Qingzhou wasn't excited. Just like the first two schemes, he also felt they had great prospects at the beginning, but all encountered dead ends halfway through.

School of Mathematics.

"You old guy, aren't you responsible for the IMO command? How do you have time to come to me?"

Chu Jiangfeng said with a smile.

"Asking the obvious." Gu Zhizhong sat down unhappily. Seeing Chu Jiangfeng get up to make tea, he said again: "That tea you made last time..."

"Okay, I might say I don't have it to others, but for you, hehe, drink as much as you want."

Chu Jiangfeng took out the small can of tea leaves from the back of the cabinet.

"You're here to understand Little Xu's situation, right? Rest assured, he's doing well, it's just that he's gone to help Li Daiyue now."

"This kid..."

Gu Zhizhong was slightly surprised, but didn't say anything. Xu Qingzhou helping his object's teacher was reasonable.

"How is his math progress?"

"Not smooth."

At this time, the office tea fragrance was melodious.

Gu Zhizhong said: "It's already December. I know you have always supported him in contacting different fields, but he will graduate and go on a public-funded study next year. Don't hang yourself on one tree. Hurry up and get a graduation thesis out. You know, young people are prone to drilling into dead ends."

"Why didn't you say it yourself?"

"Your student."

"Also your student."

"..."

The two looked at each other and laughed happily, their faces full of gratification. No need to argue; they were common students of the two.

Gu Zhizhong drank a sip of tea and said with a smile: "Actually, this kid has a count in his heart, so we don't need to worry too much."

"That's true. Don't look at this kid who is only 20 years old; this mentality can catch up with our group of old guys..."

Just as he was talking, Chu Jiangfeng frowned and realized: "You old guy isn't worried at all, you're just here to trick tea, right?"

"Cough~ Drink tea, drink tea..."

In the morning, Xu Qingzhou was calculating the local smoothing conjecture, which was quite smooth. At lunchtime, Xu Zhengyang and the other three happened to be there, so they just made an appointment to eat together.

Farm Garden.

Xu Qingzhou looked at Xu Zhengyang opposite: "Old Xu, Chen Shiqi isn't here, you actually came to the library?"

Xu Zhengyang's girlfriend was a senior this year and had already gone out for an internship.

"Heh, saying it like I'm very afraid of my girlfriend." Xu Zhengyang said proudly.

"Mainly because it's boring. People around are all rolling desperately. You know, I'm sleeping soundly every day, and suddenly I hear the sound of them getting up to wash... Damn, I can't sleep at all."

Xu Zhengyang accused Kong Xianbo and Zhai Ziqiang of their crimes.

After Kong Xianbo broke up, he seemed to have returned to the top student who looked down on everything. He adjusted his glasses: "Old Xu, depravity is the original sin. Let's study together; knowledge can create the future."

Xu Qingzhou shoveled rice. Seeing Xu Zhengyang also anxious, he asked: "Can't your Sihe Academy give you a sense of security?"

"We are decent people, not relying on home. However, how did you know that our family bought another Sihe Academy this year?"

"..."

Library lobby.

"Finally raised my eyebrows in front of Old Xu."

Looking at Xu Qingzhou's departing back, Xu Zhengyang shook his head and sighed: "Eh, Old Kong, Old Zhai, your faces are so dark. Do you want to see photos of my Sihe Academy?"

Kong Xianbo patted Xu Zhengyang's shoulder, squeezed a death smile on his face, and said: "Old Xu, you have to thank that this is a library..."

"Brother Yang, congratulations, your family has another Sihe Academy."

"Old Zhai, true brother."

"Brother Yang, I remember during military training, you made a bet with Brother Zhou. How about fulfilling it today? Rest assured, I don't have diarrhea."

"..."

Sitting in his seat, Xu Qingzhou took out his phone to chat with his girlfriend first, asking if she had finished eating.

At 3 PM, he received a call from Professor Zhao Shengwen, saying that the battery project's conclusion application had been approved, and a simple dinner would be held on Friday night, the 23rd, inviting Xu Qingzhou to join.

Xu Qingzhou readily agreed, just in time to thank Professor Zhao for the materials.

Besides talking about the dinner, he also talked about the paper on the model he built. Xu Qingzhou himself served as the first author, but Wang Wei, Hong Yayu, and Gong Yunfei were also listed as second authors.

Xu Qingzhou had no opinion.

He just did the model; the data was all made by Professor Zhao Shengwen's research group.

For Xu Qingzhou, although the ARIMA model was quite time-consuming, the difficulty wasn't great.

He had already used the ARIMA model to model the GDP data of the past 5 years and found that the model fit goodness R reached 0.92, completely meeting the experimental requirements.

Identified outliers, and through smoothing processing, reduced the influence of these outliers to a minimum.

Mathematical formula of the ARIMA(p, d, q) model: (1-φ1B-φ2B^2...)(1-B)^d y_t = (1+θ1B+θ2B^2... +θqB^q)e_t

"1.5% error..."

Xu Qingzhou shook his head: "Professor Ke Chen's requirement is a bit low."

Those who do research often want their theory to reach 100 points to be satisfied. At certain times, Xu Qingzhou also had such stubbornness.

Therefore, in the process of modeling, in addition to writing the model according to the basic mode, he also appropriately added some interesting things.

He constructed an algebraic equation about model parameters through the Maximum Likelihood Estimation (MLE) method, and then solved this equation to obtain the estimated values of the model parameters.

He also used trigonometric functions to describe the periodic variation characteristics of seasonal time series data and incorporated them into the ARIMA model for fitting and prediction.

In addition, he also used the Autocorrelation Function (ACF) plot and Partial Autocorrelation Function (PACF) plot in geometric figures, and the inversion of linear algebra matrices.

Fix bugs, reduce error values.

This model will be terrifyingly strong.

(End of chapter) ===== CHAPTER 370 =====