Chapter 203

There were more than a dozen other teams in the same computer room as Biqi.

Before 12 o'clock in the afternoon, after three hours of difficult choices, they also chose the topic one after another.

As Bizzy had predicted, none of the fifteen teams chose question C or F.

In addition to Biqi's team, there are four other modeling teams that also chose this question.

This is the news that Zhao Liang got after inquiring.

Bizzie was not surprised by this result.

In addition to the two questions C and F, the remaining four questions, only question A is more like a math problem.

In general, most of the people in charge of modeling tasks are mathematics students.

Of course, in my heart, I will be inclined to this kind of topic.

However, although at first glance it seems that only the formula derivation is needed to solve the problem unimpeded, in fact, after studying it for several hours, Bizzy found that this question has a hidden murderous intention.

The topic of question A is electromagnetic waves.

And it's not just an ordinary electromagnetic wave.

Rather, it is a fairly high-end branch of electromagnetism - marine electromagnetism!

This field of study is very high-end, but it is also very unpopular.

In China, there are very few colleges and universities that offer this major, and there are few related research results.

If you want to check the literature, you can only look at foreign literature in English.

Fortunately, Bizzy only needs a part of the content knowledge, that is, the movement patterns and laws of electromagnetic waves in the ocean, so it is not too troublesome.

Of course, this is not troublesome, it is for Biqi.

Mathematics and physics are the two most representative subjects in science.

Bizzie's talent in mathematics is so high, and his talent in physics is not far behind.

Bi Qi has not learned marine electromagnetism, but it does not prevent Bi Qi from learning and selling now.

In three hours, Bi Qi read dozens of pages of books and read four or five professional literatures, and then he understood the law of motion propagation of electromagnetic waves in the ocean.

"Let's get started!"

Bi Qi rubbed his hands together and quickly entered the state.

There are three questions in question A, and Bi Qi is now tackling the first question.

The problem requires to build a mathematical model of ocean signal reflection.

In rough seas, the reflections are weaker than those on calm seas.

At the same time, because ocean turbulence will affect the electromagnetic gradient of seawater, change the local permittivity and permeability of the ocean, as well as the height and angle of the reflective surface, the turbulent sea surface is more difficult to construct a model analysis than the calm sea surface.

In order to increase the difficulty of the competition, the people in the proposition group asked the candidates to choose the research object of course the turbulent sea.

A turbulent ocean in which wave height, current, and frequency change rapidly, and the direction of wave propagation may also change.

Biqi temporarily set the wave height, flow velocity, and frequency as the three initial parameters.

Based on these three formulas, Bi Qi drew a schematic diagram of the reflection of electromagnetic waves on the sea surface, and used the knowledge of geometry and differentiation to derive the formulas.

Entering the field he is best at, Bi Qiwen's thoughts are like a diabetes collapse, and he is leaking a thousand miles!

Lines of formulas, from the tip of Bizzy's pen to scratch paper.

[£=Rsin(π/2-△-φ0)/sin(φ0), then φ0=arcsin(Rsin(π/2+△)/R+h0)

S=∫(Pout，Pin)√1+(dy/dx(x))^2dx

x=(R+z)cos(π/2+α-θ')，α∈[0，2θ']

y=(R+z)sin(π/2+α-θ')-R

............】

Bizzie kept his head in calculations, and he didn't even have time to eat lunch.

In the blink of an eye, the time came to five o'clock in the afternoon of the first day.

Next to him, Chen Liang, who was in charge of programming, typed down the last code, pressed the spacebar, turned his head and said to Bi Qi, "Bi Qi, you want me to make the LDA (Linear Discriminant Analysis) operation program complete." ”

"Wait. Bizzie replied without raising his head, still burying his head in the middle of a stack of scratch paper.

A few minutes later, Bi Qi took a stack of scratch paper with dense formulas and data on it, sat on a chair next to Chen Liang, and entered a column of data into the program that Chen Liang had just programmed.

Then, he was writing and drawing on the paper for a while, and Bi Qi sometimes frowned and thought, and sometimes raised the corners of his mouth excitedly.

"How is it?" asked Chen Liang next to him.

Bi Qi pondered for a moment and replied, "The first question is almost half completed, and I still have two important semi-empirical formulas to calculate, and when these two formulas are derived, it will be almost enough." ”

"Then what do you need me to do next?" Chen Liang asked.

Since Bi Qi, who is responsible for modeling, has a role in coordinating the overall situation, the leader of their modeling team is Bi Qi.

"Ahh

Bi Qi took out one from the stack of scratch paper in his hand and handed it to Chen Liang.

"There is a conceptual map of the reflection of the electromagnetic wave sea surface that I drew on it, you draw it with drawing software according to the values I marked above, give it to Yunlong, and ask him to add it when he writes his paper. Bizzie spoke.

"Are there any other requirements for this picture besides the accuracy of the values?" Chen Liang strives to be perfect.

"Hmm...... Try to make it look as good as possible, after all, you still have to show it to the judges. "For example, the color of this wave, preferably the colorful blue, electromagnetic waves have no color, but we have to represent it on the map, so I need a colorful white!"

Chen Liang: "......"

"Okay, I'll try my best!" Chen nodded in agreement.

Ten minutes later, Chen Liang took the first version of the schematic diagram to Bi Qi for advice.

Bi Qi stared at the picture, touched his chin, muttered for a few seconds, and pointed to a few words, "Can you enlarge these words, otherwise the judges may have to look carefully to see clearly." However, this seems to affect the overall aesthetic feeling somewhat. ”

"Well, you zoom in on the words a little bit more. ”

Chen Liang: "......"

Chen Liang, who got Bi Qi's comments on the revision, continued to go back to drawing.

Bizzie, on his side, continued to bow his head and perform the formula on the scratch paper.

The first question, Bi Qi has already done seven, seven, eight, eight.

Only the last two formulas remain, which need to be deduced by Biqi.

One of these formulas is a semi-empirical formula for the noise of the corresponding band of the ocean.

The other is a semi-empirical formula for ionospheric attenuation.

These two semi-empirical formulas are the core of the first question.

At the same time, it is also the most difficult part of the first question of question A.

The scratch paper was written one by one by Bizzie, and at nine o'clock in the evening, Bizzie finally got the two formulas out.

Chen Liang and Fang Yunlong were eating dinner on the side, and Bi Qi sat down directly, picked up a big white flour steamed bun and nibbled on it.

Except for a breakfast at seven o'clock in the morning, Bi Qi had not eaten for more than ten hours, so he was naturally hungry.

"Bi Qi, is the first question done?" Chen Liang asked.

Bi Qi nodded, "Well, it's done, I'll send you the formula later, you get the launch path model program out, bring the values, and you will know the result." ”

After a few quick bites, the three of them returned to their respective computers and began to work intensely.

There were more than seventy hours left before the end of the race, and there was a lot of time left for them to sleep and eat, but they were not allowed to splurge it.