universal data

Chapter 342 Three Models
345 chapter

"The impact of the right-hand steering wheel scheme on the safety of motor vehicles"

"Mechanical Analysis of High-speed Vehicles Moving Rightward in my country"

"Analysis of Capacity of Two-lane Highway Based on Overtaking Behavior"

…………

"Research on Equivalent Conversion Coefficient of Expressway Vehicles Based on Simulation Analysis"

After searching the Internet for more than a dozen papers related to modeling topics, Cheng Nuo basically browsed through them at a glance.

Half an hour later, Cheng Nuo closed the last paper web page, closed his eyes, and frowned slightly in thought.

This question may seem simple at first glance, but if you think about it carefully, uh... it's really not that difficult!

But it is not so simple to be unique among the thousands of submitted mathematical models and make the judges want to award you an O award as soon as they see it.

In fact, when he was browsing the paper just now, Cheng Nuo had no less than ten modeling schemes popping up in his mind, but he was not very satisfied with them.

Because there are no bright spots and no new ideas.

Cheng Nuo was thinking.

He was thinking of a modeling scheme that would allow his team to secure an O award.

Time passed slowly.

Cheng Nuo propped his chin with one hand, and the thoughts in his mind were colliding fiercely.

The programming teammate next to him raised his wrist and checked the time: 9:15.

The game time has been played for one hour and 15 minutes.

He glanced at the other teams in the computer room.

Most of the teams have already selected topics and started working in full swing.

On their side, Cheng Nuo, the main force, had been sitting there for almost half an hour without moving a word.

He couldn't help feeling anxious, "Cheng Nuo, don't you have any ideas yet?"

Didn't that mean Cheng Nuo was cheating?But judging from today's performance, it is indeed a bit unsatisfactory!

In modeling alone, they were almost an hour behind other groups.

Cheng Nuo frowned again, "Give me another song."

"Tightly make that hug forever?" The man subconsciously continued.

I rub!

No, why did he fall into Cheng Nuo's rhythm?

Okay, then I will give you a song to see if you are as "monstrous" as the rumors say.

Four minutes later, Cheng Nuo's slightly narrowed eyes opened suddenly.

In his eyes, there seemed to be a string of data flowing.

Well, the "road" he wanted has been found.

He picked up the black carbon pen on the desktop, sorted out his thoughts, and started the preliminary modeling work on the draft paper.

After constant deduction in his mind, he decided to build a model based on metacellular automata and Monte Carlo methods to discuss the impact of the "keep right" rule.

First of all, it is necessary to break down the movement process of the car and establish the inflow model of the corresponding sub-model car-generation. For vehicles traveling at a constant speed, a following model and an overtaking model are also established.

To put it simply, it is necessary to construct three models in different situations to reflect the overtaking mathematical model required in the title.

The inflow model can simulate vehicles arriving at highway intersections. For each lane, the first six cells are set as vehicle-generation regions in the cellular automaton.

We assume that the arrival of each vehicle obeys a binomial probability distribution, let ts denote the sampling time interval and N denote the total number of vehicles within ts time, then N can be approximated to obey a Poisson probability distribution.Let Pt(N) denote the possibility of N, then we have:

Pt(N)=λ^N/N!*e^(-λ), N＞0
Following the model, in each cycle, according to the speed and position of each vehicle, calculate the gap, and then determine the driving behavior, if the gap G is safe enough...

…………

Cheng Nuo's thinking was very clear because he had already "deduced" it in his mind.

Inflow model, following model, overtaking model, three models, Cheng Nuo spent a total of less than two hours to complete the modeling through the formula.

Next, there are design rules to simulate the motion model of the vehicle.

Cheng Nuo designed two sets of regular CA models.

One set of rules for driving on the right and the other set of rules for unrestricted driving.

At the same time, a road hazard index evaluation formula is designed.

Risk factor per unit time:
d=0, Gs-Gr﹤0
d=Gs-Gr, Gs-Gr≥0
So far, the main work of modeling that Cheng Nuo is in charge of has been completed.

Looking at the time, it was only twelve o'clock at noon.

As soon as Cheng Nuo built the inflow model, he sent the data to the teammate from the School of Design and Engineering to start programming.

In terms of progress, at this point in time, he had only completed less than one-third of the work when he participated in the national competition last time.

But that time he was doing the work of three people alone, so the progress was naturally slower.

With no time for lunch, Cheng Nuo worked hard to design the distribution of acceleration and deceleration probabilities and the mechanism to avoid collisions.

Finally, all the formulas and theories were compiled and distributed to each of the two teammates.

The teammate from the School of Engineering who was typing codes on the computer saw the QQ icon flashing on the computer, he opened it subconsciously, and saw the file sent by Cheng Nuo.

File name: Question A modeling formula (full version)
He turned his head and looked at Cheng Nuo in surprise, his tone uncertain, "Have you finished it?"

Cheng Nuo unscrewed a bottle of mineral water, shrugged with a smile, "Well, it's easy."

"This..." For a while, the teammates shouldn't say what is good.

Cheng Nuo got up from his seat and said with a smile, "I'm going to the cafeteria, do you want to bring lunch?"

"Barbecue bibimbap."

"Braised chicken." The two replied subconsciously.

Cheng Nuo nodded, "OK."

Looking at Cheng Nuo's receding back, the two looked at each other and murmured softly, "The reputation of a monster is indeed well deserved!"

…………

After lunch, Cheng Nuo, who had finished his work, was bored and yawned while watching the two of them type codes and write papers.

After watching for a while, Cheng Nuo pondered.

Judging by the speed of the two of them, it would take at least tomorrow morning to finish it.But he said that he would end the competition one day, and then organize the BSD conjecture papers with Professor Fang.

It seems that I have to do something!

Cheng Nuo moved his chair, came to the teammates of the Institute of Design and Engineering, glanced at the screen, and asked, "Where is the progress?"

"The inflow model is almost programmed."

"Let's do this, I'll make the following model and the overtaking model, and you take the time to design the two sets of sports models." Cheng Nuo said with a relaxed and casual tone.

"Huh, what?!" The Jiyuan teammates wondered if they had heard the wrong thing.

Isn't programming your own task?Why did Cheng Nuo come over to intervene?

What's more, I took over the work of two model programming at once.

He has spent more than five hours programming the "inflow model", so he naturally knows how complicated these three models are to program.

He glanced Cheng Nuo up and down, "Are you sure?"

Cheng Nuo smiled, showing a row of neat and white teeth, "Of course!"

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(End of this chapter)