Hammer of Technology

"Ahem..." The man coughed twice in embarrassment before he said, "They are all brothers from China, please don't tear things apart."

Just as he was talking, someone stopped in front of the poster booth, and the man hurried up to greet him.

"Sir, if you are interested in the optimal [-]D bin packing problem, you must not miss this product."

"Okay, let's talk about it."

The man glanced at Ning Wei and Yu Xingwei, seeing that they had nothing to say, he was relieved, then turned on the computer in front of him, and began to explain.

"You see, this is a [-]D box packing software I designed to perfectly solve the problem of [-]D box packing and solve the pain of logistics waste for enterprises. The whole system consists of several aspects. First, it uses a heuristic algorithm for spatial analysis. Segmentation, spatial merging, and simple block generation, the system will automatically generate a Cartesian spatial coordinate system based on the data entered by the enterprise..."

"I'm going, what is this?"

Watching the man show and introduce, Ning Wei asked Yu Xingwei next to him in a low voice.

"It seems that the heuristic algorithm, tabu search algorithm, ant colony algorithm, and simulated annealing algorithm are all integrated into one software?" Yu Xingwei said uncertainly.

"So where is the innovation?"

Yu Xingwei glanced at Ning Wei with complicated and unspeakable eyes, and said: "Mr. Xiao Ning, don't you think that every technical person in the world is a genius? Can you integrate existing things and make them play better?" Great efficiency is already a rare talent, and it is already regarded as innovation. As for directly creating a field that has not been set before, and directly solving problems that cannot be solved by the predecessors, how many people in this world do you think can do it? What? He is at most a false propaganda, but this is not in China, who cares about him?"

This makes sense, Ning Wei nodded, and said, "Brother Yu, don't praise me in such a way all the time, I'm sorry."

Yu Xingwei: "..."

During the conversation between the two, the foreigner who was introduced by the man finally shook his head, left without leaving the man's contact information and information.

Ning Wei and Yu Xingwei also planned to leave, but after listening to the introduction, they felt dull, and a slim figure suddenly appeared in front of Ning Wei.

Ning Wei raised his head and glanced, only then did he realize that it was the female school bully who fell behind his support yesterday. People are like this, changing a suit of clothes can have a different temperament.

A smart and decent little suit, paired with a pair of gold-rimmed glasses, immediately looks like a female doctor, and with a stern face, she looks like a goddess, but Ning Wei only feels headaches, and what's more, is When seeing the beauty walking towards the two of them, Yu Xingwei took a step back shamelessly.

"Miss Ron..."

"Don't call me by my last name, just call me by my first name, my name is Lucy!"

"Well, Lucy, I really didn't mean to yesterday."

"It doesn't matter. I already know that your name is Ningwei. I have your report meeting this afternoon. Last night I almost stayed up all night to re-study your paper and prepare more questions. So, Ningwei, please Get ready to take the call."

After finishing speaking, Lucy glanced at Yu Xingwei, then turned around and left gracefully.

Now Ning Wei lost all intention of continuing to wander around the poster area, turned his head to Yu Xingwei who had no loyalty and said, "Brother Yu, let's go, let's go to the report meeting."

"Wait, Ning Wei, I heard that when a man changes his mind because of a woman, he likes it. Don't you like that Lucy?" Yu Xingwei asked worriedly.

After this trip, if Ning Wei had a girlfriend in the United States, he felt that his end might be miserable after returning to China...

Hearing this, Ning Wei was shocked, and looked at Yu Xingwei in surprise: "Brother Yu, where did you hear this argument?"

"On the Internet, I think it makes sense."

"It is also said on the Internet that women have big breasts and no brains. Do you think it is appropriate to use it on the woman just now?"

Yu Xingwei shook his head without hesitation.

"Isn't it? Brother Yu, did you actually observe it?"

"I……"

"Okay, Brother Yu, let's listen to the conference report seriously."

……

When Ning Wei and Yu Xingwei approached Lecture Hall No. [-], the large conference room that could accommodate at least a thousand people was almost full.

Of course this is also understandable.

Generally speaking, the higher the ranking of the reports of such top academic conferences, the more attention is paid to the contents of the reports.

As an opening academic report, it will naturally attract more people to come to observe and learn.

What surprised Ning was that the staff standing at the door of the lecture hall did not check the invitation letter issued by the organizing committee.

It was only later that he learned that if there were extra vacancies in this kind of meeting, it would not be easy to restrict the entry and exit of people.Of course, if you want to get a front-row seat where you can ask questions, that ticket will come in handy.

Although I didn't feel very interested in the first report based on quantum behavior particle swarm optimization at the report meeting at first, but I really listened to it. In fact, I felt quite interesting, but that's all.

Simply put, this is an algorithm developed from the advanced swarm intelligence algorithm.

A typical representative of the swarm intelligence algorithm is the particle swarm optimization algorithm that simulates the behavior of the bird group, referred to as the PSO algorithm.Since this algorithm was proposed in 1995, it has attracted the attention and research of many scholars in related fields at home and abroad because of its simple calculation, easy implementation, and few control parameters.

But the algorithm's features stand out as much as its advantages.

First, theoretically speaking, it is not a global convergence algorithm; second, the speed and position evolution formula of the algorithm makes the randomness and intelligence of the particle swarm low; in addition, the dependence of the algorithm performance on the upper limit of the speed makes it less robust.

People have advanced this algorithm by thinking about this algorithm and introducing the concept of particle swarm optimization.

Its application fields are mainly in multi-peak, multi-extreme function optimization problems, complex engineering optimization problems, such as stochastic programming, system identification, etc...

But after a 10-minute break, when the second report officially started to introduce a new random algorithm, Ning Wei found a difference.

This is no longer a question of whether it is interesting or not, but with the continuous in-depth explanation of the speaker on the stage, his brain responded again, listing many problems that the algorithm urgently needs or should solve.

This is very interesting.

You must know that the first report meeting was a 60-minute report meeting, but the organizing committee of the second report meeting today only gave Professor Lermontov 45 minutes on the stage. Don't underestimate these 15 minutes. It is the difference in the degree of importance that the top group of people in the field of computer algorithms attach to the two.

However, Ning Wei only found it interesting while listening to a lecture, and nothing else.

After listening to the second report, many associations were automatically generated, and many ideas popped up.

So this means that this new random algorithm is more valuable to his current research, or that the innovation of random algorithms has a greater role in advancing the field of artificial intelligence?

Ning Wei didn't want to understand this question for the time being, but he listened more seriously, and then silently remembered the professor's name in his heart, and carefully checked the professor's paper when he was going back.

……

The three reports in the morning ended with Ningwei thinking about immersion and algorithms.

Compared with this kind of top-level conference, the report meeting on the first day is actually a bit intensive. In the 180 minutes from 150:[-] to [-]:[-], there are [-] minutes of high-quality reports. Not very friendly.

There are too many unrelated but full of dry things to digest, which is not an easy task.

Ning Wei only felt that he had gained a lot. Until the end of the last press conference, his mind was still full of ideas for improving the random algorithm. He even felt that he could faintly feel the pulse of the development direction of the artificial intelligence field, but he never Think too clearly.It's like a slim beauty hiding behind a hazy veil, but he still can't lift the veil to get a glimpse of the whole picture.

This feeling was so disturbing that he almost forgot that two hours later, he would have to sit on the rostrum to report to thousands of industry elites.As for the Harvard beauty genius who wanted to find fault, he had already thrown him out of the sky.

Until the end of the last report meeting, he was still staring at the big screen showing the PPT in a daze.

Until Yu Xingwei patted him heavily on the shoulder: "I said Ning Wei, what are you thinking? You didn't hear the two calls? You are going to eat, aren't you hungry? I digested the two pieces of bread in the morning It's over!"

"Oh!" Ning Wei stood up regretfully, and suddenly asked: "Senior Brother Yu, have you thought about the direction of the doctor's topic?"

"Huh?" Yu Xingwei was stunned for a moment, and said in astonishment: "Please, I was caught by you in the project team as soon as I was a Ph. .”

"How about choosing a random algorithm? I have a feeling that this direction will definitely be useful in the future." Ning Wei said with certainty.

"Huh?" Yu Xingwei was stunned.

Ning Wei very smoothly turned his little annoyance into Yu Xingwei's little entanglement.

For a Ph.D., topic selection is a very sacred matter. It is related to whether he can graduate or not, and it is even more related to his employment prospects after graduation.

So, when Ning Wei had sorted out his emotions and sat on the rostrum of the conference, and was about to start his report, Yu Xingwei was sitting in the audience struggling, what exactly did Ning Wei mean?Why do you suddenly recommend him to choose the direction of random algorithm?

……

"As we all know, the framework of fluid mechanics includes eight subdivisions, including turbulence and transition, as well as artificial intelligence and machine learning. The turbulence algorithm is the application of the NS equation solution in a special case. We all know The NavierStokesequation of physical space is essentially the most concise and efficient expression of a flow field, and the first step of the turbulence algorithm is to transform a network space where data lives into an intuitive physical space..."

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113 Come on, let number theory govern your fears

What kind of experience is it like to give a 60-minute report in the lecture hall of the world's top conference with thousands of people?

To put it bluntly, Ning Wei really can't answer this question. If he tries to answer it forcefully, he can probably only say one thing, which feels okay.

Because even if you have already started to sit on the rostrum, you can clearly see the rows of heads below, and you can even find Professor Shen who is sitting in the first row, that Ms. Lucy who can switch styles freely, and the person he is most familiar with. Yu Xingwei.

But his complete thoughts were still not in the meeting. The mathematical formulas that kept popping up in his mind directly turned the industry leaders and technical officers of top technology companies below into mathematical symbols.

how to say?

When he had this feeling for the first time, he started to struggle with the NS equation, and gave birth to the turbulence algorithm; the second time he felt this way, he started to study artificial intelligence, and would rather apply for it a year later for the postgraduate entrance examination. EDA project; and today, this is the third time.

It was as if there was something in his brain guiding him in the direction he should go. When he encountered a similar in-depth explanation, it would activate, promote the secretion of dopamine, make him toss and turn, and make him unable to stop...

Or maybe his brain wants to do something, big things.

So nervous?nonexistent!

What mathematician gets nervous at the sight of a thousand mathematical symbols?Even if he was nervous, he was afraid that he would be impulsive and apply for a new project.

You must know that he promised Lu Dongyi that next year he will also climb to the School of Mathematics of Yanbei University to continue the research of number theory.

At this time, Ning Wei was just explaining the summary he had already prepared purely according to inertia.As for what questions these people would ask, it was completely out of his consideration, and he didn't even bother to expand the report based on the content on the PPT in order to extend the report time and reduce the question time.

So the report, which was originally planned to be completed in four to 10 minutes, turned to the last page of the PPT in half an hour.

Of course, these trance emotions are basically invisible to the audience, because Ningwei's language is still fluent, and the necessary data quotations come as soon as he opens it, with almost no lag.

So when he finished speaking so quickly, he was the only one who was surprised...

"Uh, um, the above is the design idea and method overview of the turbulent flow algorithm, thank you everyone."

There was a burst of applause from the audience, not too enthusiastic, but more polite.

After all, it takes at least a week or more of research to get a rough outline of a groundbreaking paper, and it needs to be condensed into an abstract that can be reported in an hour and a half. In fact, there cannot be too much internal dry stuff.

At least he cannot describe in detail the processing of each data iteration in the paper, the divergence and convergence of functions, each recursive judgment, screening, and the meaning of associated functions or equations.

Ning Wei didn't know that many of the thousands of people in the audience had carefully studied his thesis, but he was sure that if he hadn't done his homework beforehand, he would have read his thesis three times and made notes. Under the circumstances, it must be incomprehensible.

So the applause didn't move him.

He just sat quietly in his seat, allowing himself to focus more on the meeting, waiting for the bigwigs in the audience to ask questions.

Similar to what he thought before, the first two bigwigs who asked questions focused on the content of space transformation ideas during algorithm iteration, which is also the most obscure part of turbulent flow algorithm in a theoretical sense.

So Ning Wei was well prepared and spent 10 minutes explaining the general idea and showing a more detailed derivation process, especially the process of the defined limiter limiting higher-order terms as the flow field parameter space changes.

Then he saw on the stage that the microphone was handed to Lucy Ron, the genius girl from Harvard that Feng Shaojie called.

"Mr. Ning, hello, after listening to your report, I have noticed that the latest experimental data you announced in today's report is quite different from the experimental data in the original paper. It should be a great improvement in the latest testing stage. .In the process of studying the paper, I roughly understand that the algorithm learning stage mainly relies on the training set, and the training set comes from high-quality measured data rather than data simulation.”

"So when I was researching the paper, I suspected that the reason why the laboratory error reporting rate described in the paper remained at a high level for a very long time and could not be lowered was most likely due to the noise interference caused by random errors, which is the most difficult problem of this type. . But in your report just now, I found that the false positive error rate of the algorithm has been greatly reduced, so I would like to ask how this is done?"

Ning Wei looked at the solemn-looking girl under the stage in surprise, and probably understood why Feng Shaojie said that she was Harvard's favorite, obviously not because of her figure, but because of her mind.

He has never been in the laboratory for a day, and he can determine the reason for the high error rate of the turbulence algorithm before the update from his paper alone. This makes Ning Wei never dare to look down on the heroes of the world. A high school bully who is open-minded, he pays equal attention to his proud figure and smart mind.

After all, they spent nearly a month observing the data in the laboratory every day at that time, but they didn't find out the problem.

Just to answer the question...

"The solution to this problem is not universal. In fact, it is through a deeper understanding of the NS equation itself. Simply put, it is solved by setting a high-level space to limit the amount of data overflow. If you must listen to the complete solution, I I don't know...whether there is enough time." Ning Wei explained.

In fact, he wanted to say that he didn't know if this girl could understand, because the content in the field of pure numbers did not belong to the special research category of algorithm engineers.But saying this was too hateful, so Ning Wei temporarily changed his words.

It's not that he looked down on people, he just simply recalled the days when he discussed and argued with Lu Dongyi for five days...

However, Lucy in the audience just smiled and said relaxedly: "There are still 10 minutes left. I believe that with your ability, you can solve everyone's doubts."

Ning Wei glanced at Professor Shen under the stage, just smiled slightly, then nodded helplessly, and said, "Okay, then I need an electronic pen, thank you."

After finishing speaking, Ning Wei directly removed the prepared PPT, created a new blank document, and then took the electronic pen sent by the field manager, and began to write on the document.

Soon after a series of formulas were written, they were simultaneously displayed on the big screen behind. Ning Wei also officially began to explain: "Is this measurable function understandable? I won't explain more because of the limited time. The minimum value of the above function conditions is recorded as ∥f∥Lp( )..."

Why is there a saying in the academic circle that the field of pure numbers stands at the pinnacle of the academic research chain of contempt?

Because number theory is really high and low.

To put it bluntly, number theory researchers and ordinary people view the world in a different way.

Especially after modern number theory subdivides the field, it is not accessible to ordinary people.Because many times, those who study number theory at the same time may not be able to understand the thinking of their peers once they cross the border.

For algorithm engineers, mathematics is naturally extremely important, but the research of algorithms is to solve the real problems we are facing now, and for the research of number theory, it is not important whether it can solve real problems, or even solve the problems that may arise in the future Neither is important, and the fun of its research is more inclined to the philosophical exploration of the nature of the world.

Take the study of NS equations as an example, wouldn't physicists be able to study fluid mechanics without NS equations?The answer is obviously no.

The essence of physics lies in observation and experimentation. One time is not enough for a hundred times, a hundred times is not enough for the previous time, or even millions of experiments in different environments. Through observation and records, it is enough to summarize various general laws under different fluid conditions, so as to derive There are various formulas for different situations.

In fact, modern physics does the same.