All-round mathematician

Chapter 218 The Process of Struggle

The freshmen are officially in class, and with the dean's care, Yang Fan continues to follow the progress of the sophomore class.

In the first year of high school, the solution is over, and the second year of mathematics must be studied, plus ordinary differential equations, functions of real variables, functions of complex variables, differential geometry, operations research and cybernetics.

Real variable functional science ten times, functional analysis heart fan cold.In the middle and late stages of Topology, even a top student has to kneel.

In the freshman mathematics class, Yang Fan often saw his classmates exchanging their experience in mathematics and asking for course materials.

Mathematics majors in universities have at least 3 levels of difficulty, Mizuki, and the difficulty goes directly to the top.

Yang Fan has already suffered this heavy blow once, and the high and low numbers are really not in the same order of magnitude.

It is basically no problem to complete the credits, as long as you do the exercises explained in the teacher's class and the exercises in the book.One hundred percent energy is not enough to learn to be thorough.

The sophomore class didn't find it strange that Yang Fan appeared.At this moment, his identity has changed, he is no longer a senior high school student, but a world-renowned Mizuki Xueba.

As the difficulty of learning increased, Yang Fan found a strange question, why the span of domestic mathematics courses is so large.

Feng Yao also once said this problem, it seems that there is a gap from low numbers to high numbers.

Do you want to translate or write a general teaching material, step by step from easy to difficult.

The more he thought about it, the more he felt that it was feasible.It's just that with his knowledge, he is still a little bit accumulated, and his spirit is high, so there is nothing he can do if his ability can't keep up.

The most important thing in front of us is to overcome mathematical modeling.The two in the dormitory had him staring at them all the time, but they worked hard and watched Teacher Mizuki Xiejin's open class over and over again.

And Yang Fan is also desperately brushing up on the knowledge of modeling, and he can't tell where it is, lack of reference and comparison.

On September 9th, Friday, the National Undergraduate Mathematical Contest in Modeling began and lasted for 9 hours.

At this moment, there are at least 8 to [-] mathematicians looking forward to it. At [-] o'clock, the online question bank will be issued.

(A) Sun shadow positioning

(B) Taxi resource allocation in the era of "Internet +"

(C) Willow head on the moon
(D) Crowdfunding housing planning scheme design

The competition is divided into two levels: undergraduate and specialist, with AB undergraduate topics.

"Brother Yang, what shall we choose?" Pan Zhe said.

The division of labor has been confirmed by the three of them. Yang Fan is considered to be the temporary director, and he is responsible for the final completion of the thesis.

In terms of inquiring about Pan Zhe's inquiries and writing programs, Su Jun'an mainly focused on graphics and modeling, and finally, Yang Fan summarized them.

"What do you think?" The three of them are a group, and Yang Fan doesn't want to let him decide everything.

"Compared with previous question banks, there are one practical question and one virtual concept. The AB questions are just divided into categories. I agree to choose A." Su Junan took the lead in making a suggestion, "A is mainly about theoretical knowledge, and it is relatively easy to find information. In terms of complexity, I think A is better. It can set off our Shuimu mathematics background."

"Old Su, you are wrong." Pan Zhe objected, "Taxi hailing in the city is a big problem. The emergence of online car-hailing may be because the above people want to find some feasible solutions. The finalists may be applied in practice. We major in mathematics, It’s about applying what you’ve learned.”

The two turned their eyes to Yang Fan, and it was up to him to decide.

Yang Fan weighed in, the two roommates were right, and AB didn't matter at all, and the results were still based on the modeling paper.

As for solving the problem of taking taxis, Yang Fan does not take it seriously. The country has countless talents, and the number of graduates in mathematics is not enough to require college students to come to the end.

"Pick A, I like astronomy very much."

Yang Fan gave the answer, and Su Jun'an and Pan Zhe acquiesced, they stopped asking nonsense, and put efficiency first.

Download the topic and open the WORD document.

Question: For the sun shadow positioning technology, through the law of relative motion between the sun and the earth, establish the relationship between pole length, shadow length, latitude and longitude, time, and date, and establish a model.

Calculate the relationship according to the time difference, when the Beijing time is 9:00-15:00, the time of Tianmen Square, and apply the established model.

Calculate the length of the shadow according to the shadow coordinates, fit the function of the capital time and the length of the shadow, find out the lowest point of the shadow length, and then calculate the local longitude according to the time, and determine the possible location.

When the topic came up, Su Junan and Pan Zhe were slightly paralyzed. They understood the content, but they didn't know what they were talking about? This was even more puzzling.

"Where to start?" Su Junan asked.

Yang Fan frowned and thought, and gave an order: "Brother Pan, search for real solar time, mean solar time, declination angle, solar altitude angle, entropy value method, download all the materials you think you don't understand, and mark keywords, papers, etc. All famous sources."

"Su Ge, analyze the diurnal and annual changes in the angle of the sun's rays hitting the object, causing the length and orientation of the object's shadow to change regularly, and use Matlab software to draw the image of the shadow length changing with time."

The big problem of sun shadow positioning is divided into two small problems, and there are four steps to answer respectively.

First, model assumptions.Second, the notation used in the model, and third, the modeling.Fourth, calculate.

Regarding the first question, Yang Fan quickly grabbed a pen and paper and put forward six hypotheses:

1 Assuming a single light source illuminated... 6 Considering the entire sky as a celestial circle.

Define 12 symbol settings, declination angle, incident angle...shadow length.

The key is modeling, setting up graphics, and calculating model solutions.

……

For three days and three nights, none of the three left the dormitory.Meals are sent directly to students.

At 4 a.m. on Monday, Yang Fan finally completed the last step. Looking at the 24-page thesis on the document, he still felt proud.

The graphics are rich and well-founded, and various complex calculation formulas are dazzling.Without any cheating methods, it was completed by the accumulation of knowledge of the three people.

Su Jun'an and Pan Zhe fell asleep on their desks at some point.The final summary homework was done by Yang Fan alone, and they couldn't help.

His eyes were bloodshot, his face was stubbled, and his face was pale, but his brain was extremely excited.

"Wake up." Yang Fan pushed the two of them.

"What time is it?" Pan Zhe raised his head in a daze. The closed curtains and the lights in the dormitory that had been turned on for a long time made them lose their sense of time.

"finished?"

Yang Fan nodded, and Pan Zhe jumped up happily, screaming: "Old Su, get up, it's over."

Dozens of pages of documents, Pan Zhe slowly pulled down like a pilgrimage. The spherical graphics, curved graphics, and dense formula calculations all made him intoxicated.

"It's not easy."

Su Jun'an also woke up, leaned behind him, followed the beauty of the paper, turned his head and said: "Brother Yang, don't play on your own in the future, brothers can't stand it."

"Brother Su, it doesn't matter if you don't get good grades in the thesis." Yang Fan opened the curtains, and the stars were shining outside: "What we enjoy is the process of hard work. Don't you think these three days and three nights will be a fortune in life?"

The dormitory is quiet.

Pan Zhe yelled with a smile: "Don't pour poisonous chicken soup, come and sign it, and send it. I still hope that this paper will win an award, so I will add some credits."

The results won't come out until a month later, but the three of them don't care.

(End of this chapter)