Chapter 542: The two places are linked together and calculations begin!
"...Eat an axe?"
On the open ground.
Hearing these words coming from Sun Jun's mouth.
Lao Guo couldn't help but look stunned, and there was a subconscious look of confusion on his face.
But soon.
He reacted and couldn't wait to ask Sun Junren:
"Old Sun, you mean...the radar verification is correct?"
Sun Junren nodded when he heard this, pointed at the equipment in Lin Yu's hand, and explained with a slightly complicated expression:
"Yes, according to the data results of this filter produced by Kobayashi, there is no problem in terms of power spectral density, impulse response or chirp signal."
"These are the core attributes of a radar, even a brand-new category like Doppler radar is no exception."
"In other words...this weather Doppler radar fully meets the requirements in terms of parameters."
Hearing Sun Junren's words.
Xu Yun couldn't help but glance at Lin Yu, who was squatting on the ground not far away.
Matched filter.
This is a relatively early method in radar signal verification.
After all, in the early days of radar development, drones had not yet appeared, so it was difficult to get the target into the sky - the feasible ideas were basically airplanes or hot air balloons.
However, the former costs more, and the latter is prone to leaks if it is a confidential project.
under such circumstances.
The envelope matched filter came into being.
As we all know.
There are four types of radar receiving signals:
Signal,
noise,
interference,
and clutter.
Among them, signals such as noise are also the biggest external factor that challenges radar receivers.
Because noise does not carry any required information and is mixed into the useful signal, it will reduce the latter's recognition in disguise and distort the information.
But again.
Since the phase of the noise is random, only incoherent superposition can be achieved.
Therefore, noise, a seemingly useless "pure waste", makes radar signal verification possible from another angle.
The essential principle of the envelope matched filter is the complex envelope of the signal.
That is, the Fourier transform is used to simulate the same amplitude-frequency characteristics of the signal, thereby emitting a signal with a certain carrier frequency and transmitting it to the radar.
These signals are different from noise, but can only achieve incoherent superposition.
It is a decentralized state.
After these signals are processed by various components in the radar, more detailed values can be screened out, thereby achieving a verification and correction effect.
This principle is not difficult to understand, so what really surprised Xu Yun was...
Listen to Sun Junren's description.
This envelope-type matched filter used to test weather Doppler radar seems to have been invented by the little girl named Lin Yu?
This is very unusual.
After all, the above principle involves WVD... which is the Wigner-Willi distribution.
At present, the theory of non-stationary signal analysis has probably not entered the country yet. There are probably no more than five people in the country who have mastered the relevant theory.
So she is either an overseas student who has just returned from her studies.
Either that...
Self taught?
In short, no matter what kind of talent he is, he is a rare talent in this era.
Of course.
Xu Yun's surprise was fleeting, and his attention was quickly attracted by Lao Guo's next sentence:
"Old Sun, since there is no problem with the radar, can't we start collecting meteorological data now?"
As soon as Lao Guo said these words.
You could hear the needle drop immediately at the scene.
Swish——
Within one second.
Everyone's eyes were fixed on Sun Junren at the radar console.
And at least half of the onlookers had expressions of anticipation and apprehension on their faces, looking eager to give it a try.
These onlookers have either participated in the production of radar or are calculation staff at the meteorological center, and they all know one thing:
Radar debugging is not the focus.
Everything they had done before was actually for...
Collection of meteorological data!
Only meteorological data and this information are collected,
Only at the base can we have the opportunity to carry out weather simulation calculations, and can we accomplish some extremely important goals that may even affect the overall situation.
"..."
Looking at the faces in front of me that are full of anticipation and nervousness.
Sun Junren was silent for a moment, nodded, and said to Lao Guo:
"Yes, in theory, we can start collecting data now."
Hear this.
Lao Guo's expression remained unchanged, but his left hand quietly clenched into a fist.
this moment......
It's finally coming.
Then he took a deep breath, turned around, and said to Li Jue's assistant Zhou Cai, who had just arrived at the scene not long ago:
"Xiao Zhou, please go and confirm with each department again."
"If they are all ready, then let's officially start data collection. As the saying goes, it's better to choose the day than to hit it."
Zhou Cai's expression became solemn:
"clear!"
Say it.
Zhou Cai turned around and walked towards the tent not far away.
In order to facilitate the transfer of information, the factory office specially connected a telephone line to the tent this time, which is only more than thirty meters away from the radar.
Zhou Cai walked to the phone in a few steps, took out a brochure from his body, and dialed the number skillfully:
"Hello, 9527, please help transfer to factory 503..."
"Yes, it's me..."
"Oh, okay, thank you..."
A few minutes later.
After making several phone calls, Zhou Cai closed the booklet, carefully put it back on his chest, and quickly returned to Lao Guo.
He first glanced at Xu Yun quickly, then lowered his voice and said to Lao Guo:
"Gong Guo, comrades from the Telegraph Center, the Secrecy Front and the Capital Computer Institute are all ready and can cooperate with the data simulation at any time."
Upon hearing this, Lao Guo patted Zhou Cai on the shoulder and asked Ye Duzheng beside him:
"Comrade Duzheng, where are the comrades from the Meteorological Center?"
Hearing this, Ye Duzheng and Tao Shiyan looked at each other with extremely solemn expressions:
"Guo Gong, don't worry. There are 37 people in the meteorological center. They are all in place today and ready to go into battle at any time!"
To describe data calculation as a battle shows how excited Ye Duzheng was at this time.
In a sense.
This is the Meteorological Center's battle for revenge and proof.
If there is sufficient data, it is impossible to calculate the short-term weather trends in the future....
Then there is really no need for the Meteorological Center to continue to exist - at least that is what Ye Duzheng himself thinks.
I saw that all departments were in place.
Lao Guo, who had already obtained the authorization from the organization before today, no longer hesitated and said decisively:
"Very good, in that case...Old Sun, turn on the phone!"
snap——
The words just fell.
Sun Junren decisively pressed the main control button of the radar.
After a while.
Buzz buzz——
The weather Doppler radar that was originally on standby sounded the startup sound again.
But this time, the radar no longer turned left and right as before.
Instead, he raised his head slightly, and the two X-band cross bulges slowly moved towards the sky.
at the same time.
In the microscopic world invisible to everyone.
Waves of pulsed electromagnetic waves with special frequencies began to spurt out from the bulge towards the sky.
If you add a sound effect at this time, it should be...
biubiubiu?
These electromagnetic waves instantly shuttle to the upper atmosphere at a speed close to the speed of light, and interact with the atmosphere in various ways during their propagation.
For example, non-spherical particles scatter circularly polarized waves, causing depolarization.
Another example is the scattering of incident waves by the uneven refractive index structure of air and the ionized medium formed by lightning discharge.
as well as......
Water vapor condensation in the atmosphere scatters and absorbs radar emitted waves.
That is...
The motion of the scattering target within the scattering volume affects the incident wave...
Doppler effect.
Five seconds later.
stop--
There was a very light sound coming from the metal box of the storage system, and it seemed like some kind of disc was starting to rotate at high speed.
Another fifteen seconds passed.
Various numerical values began to appear on the screen in front of Baozheng.
0.......
0.......
1.......
1.......
2.......
5.......
at the same time.
Da da da--
The delayed storage device and dotting timer next to the storage device also quickly began to output content.
See this situation.
Ye Duzheng, who had been waiting here for a long time, took several subordinates and quickly collected the notes and passed them to the telegraph teams in other tents.
Didi didi——
The telegraph operator began to send telegrams with the speed of an eagle. In future generations, Zaun will be the king.
And at the same time the telegram was sent.
Institute of Computer Science, Chinese Academy of Sciences.
Telegraph mailroom.
Wu Jikang, then deputy director of the Computer Institute, was standing next to the receiver, staring solemnly at a printing device in front of him.
According to the original plan.
Wu Jikang has a key meeting to attend today, which is related to part of the current development plan and short-term results of the 109 aircraft.
But after learning that Lao Guo and the others were going to conduct a radar test.
He took the initiative to cancel the meeting and chose to stay in the office.
First, the components of the weather Doppler radar are quite special, involving the storage equipment of the 109A aircraft.
Although the 109 armor machine was only half completed, and the organization had decided to reassemble a new equipment.
But as the person in charge of the research and development of the 109 machine, Wu Jikang still wanted to know whether the storage module could operate normally - after all, he had never had the opportunity to encounter this kind of actual combat before.
The second is...
If the weather Doppler radar can really obtain the expected data, then it is estimated that computers will be indispensable to assist in simulations in the future.
Therefore, regardless of emotions or reasons, Wu Jikang must pay attention to the progress of this project today.
Why haven't you come yet...
Just when Wu Jikang was slightly lost in thought, the telegraph operator beside him suddenly raised his voice:
"Director, the telegram is here!"
Wu Jikang quickly came to his senses and looked at the equipment.
as expected.
At this time, new telegrams had begun to be typed on the telegraph machine.
And it is different from the previous telegram about Doppler radar.
What Factory 221 sent this time was purely meteorological data, and there was no need to keep it confidential.
The data content is not heavily encrypted and can be interpreted directly.
So it's very fast.
A large amount of data was summarized in Wu Jikang's hands.
Wu Jikang quickly took these data to the computer room on the same floor, which was a warehouse with an area of more than 100 square meters and housed computer No. 104.
The main body of the 104 machine is more than 60 square meters in size, and the display screen has about 50 pieces, which is about the same size as the tablets of later generations.
At this moment.
In front of more than fifty screens, there is a computer operator with a formal expression, both male and female, all in their twenties.
They are the first batch of computer science graduates in China who graduated from the University of Science and Technology of China.
If Xu Yun can fly here and have sex with one of the short-haired lesbians, he can also become the adoptive father of a professor in the Department of Mathematics of the University of Science and Technology in the future...
"Xiao Lin, Xiao Wang, Xiao Chen, come and help me send the data!"
After entering the computer room with the first batch of data.
Wu Jikang quickly walked to the team leaders on the front left, distributed their respective data, and told everyone:
"After everyone gets the manuscript, you can start importing the data. Your task is of great importance. Remember to be cautious and don't make mistakes! Do you understand?"
The audience quickly responded with a unanimous response:
"Understood!"
Wu Jikang still had a sullen face and looked very serious.
Actually.
Considering that there is a lot of data entered this time, if there is an error in some data, it will not affect the final result too much, so the above has also given a 3% error tolerance rate.
However, Wu Jikang did not tell the operators about this, fearing that they would have an accident because they were relaxed.
A few minutes later.
Each operator got the corresponding data in their hands and started importing it.
Mentioned earlier.
Lao Guo and his colleagues originally collected more than 500 sets of data with their instruments, but later Ye Duzheng's calculations revealed that these data were completely insufficient.
This chapter is not finished yet, please click on the next page to continue reading the exciting content! To complete the weather simulation, it must be 100,000 times more.
That is to say, more than 50 million sets of data are needed.
However, this is only the data required for calculation, and the workload of importing is not that much.
Because after passing the two levels of electrostatic analysis and X dual-band, these data will be classified into a more standardized range:
This interval is refreshed approximately once an hour, and similar values will be superimposed and directly entered through the electrical signal of the photoelectric conversion element.
Therefore, when it is transferred to Wu Jikang and others, the amount of data that needs to be manually imported is far less than 50 million sets.
Take the Rabbits’ first weather Doppler radar as an example.
The first domestic meteorological Doppler radar model is called 714SD. It can collect up to 14 million sets of data at a time, every fifteen minutes.
However, during the actual calculation, the electrical conversion element filtered out 98% of the same values.
Therefore, the data that really needs to be manually imported is only a few hundred thousand groups - note that importing and calculation are two different things, and the actual calculated data is still 14 million groups.
Although 50 million sets of data may seem like a lot at the moment, only about a million sets of data need to be entered manually.
Nowadays, there are more than fifty people in the computer room, and each operator actually has to enter about 30,000 sets of data.
True, 30,000 updates per day.
Then very quickly.
Many operators began to enter data.
"The temperature is 26.7℃..."
"Humidity 27%..."
"Meridional wind 18.5m/s...."
"Scattered radiation 220W/m^2...."
Mentioned it a long time ago.
It is different from RF-CMAQ and other models used in later weather calculations.
Meteorology at this time was still in a very primitive stage.
Therefore, even if there is a huge amount of data, predictions can still only be made by solving the atmospheric equations.
That is, as mentioned before, the earth's surface is gridded, and then the values of each meteorological element are interpolated to obtain the value at a certain moment in the future.
Therefore, the actual model derivation still needs to be carried out by Ye Duzheng and others. The 104 machine of the Chinese Academy of Sciences mainly fits various data into more accurate parameters.
In the words of later generations...
Processed into semi-finished products?
Of course.
Although the technology of this era was relatively backward, it was finally separated from the early stage of modern history.
In addition, the Computer Institute is the most advanced technical center of the Rabbits, so the 104 machine is not so primitive as to be particularly miserable at this time.
Although the current 104 machine is still free from the limitations of not understanding equations, the algorithm it uses...or the idea is actually quite special:
The time resolution is 1 hour, covering 6 vertical levels, and the decoder has only two levels.
More importantly...
Its mathematical background mechanism comes from the Institute of Mathematics led by Mr. Hua Luogeng.
That's right.
Hua Luogeng.
Therefore, although it is still a brute force calculation.
However, with sufficient data, the simulation of the 104 machine went quite smoothly.
that's all.
Every once in a while, a batch of data is transmitted from Factory 221 to the Computer Laboratory.
The operators of the computer lab imported the data, and the 104 machines used the computing power of a classic car to slowly produce results.
.......
Eight hours later.
A five centimeter-thick data result was officially released.
The originally scattered atmospheric particle data has been classified into parameters in various time domains, wind fields, pressure fields, density fields, and many other more detailed models.
Immediately afterwards.
The data was encrypted and sent back to Factory 221, and finally found its way into the hands of Ye Duzheng and Tao Shiyan.
[A novel app that has been running stably for many years, comparable to the old version of the source-changing app, huanyuanapp, that is used by all chasing bugs.]
So far.
The entire meteorological deduction has also reached the final stage.
That's the Meteorological Center...
Human power correction and derivation.
"Comrades."
Inside a large temporary tent.
Ye Duzheng and Tao Shiyan glanced at the many colleagues in front of them, looked at each other, and heard Ye Duzheng say:
"A week ago, our calculation results unfortunately failed because the data was not of sufficient magnitude and we underestimated the mystery of nature."
"But today, we have more data, which has been processed by computers and compiled into the parameter file in front of me."
"Originally, Mr. Zhu Kezhen from the capital proposed the idea of handing this document over to the Capital Meteorological Bureau for processing, but I rejected it - this is our 221 Factory Meteorological Center's opportunity to avenge our shame, and no one can compete with us!"
"For this reason, I also issued a military order in front of the factory leaders. If there is another miscalculation this time, everyone involved in the data derivation, including me, will report to the livestock sideline team immediately!"
Say it.
Ye Duzheng looked around the scene, softened his tone slightly, and continued:
"Of course, if you have any objections to this, you can withdraw from the next calculation task now."
"Members who withdraw can continue to work in the meteorological center. After all, it is impossible for the base to completely abandon such a department, so..."
"Comrades who want to quit now, you can leave."
Finished saying this.
The scene instantly became silent, as if the breath had frozen.
But in this dead silence.
But no one stood up from their position and left.
There was a fire burning in the hearts of everyone present.
This fire is not anger, nor is it grievance.
It's a simple urge to prove one's worth.
in the past few days.
Although the factory did not punish them, members of the meteorological center had heard some rumors.
no way.
After all, there are tens of thousands of employees in the entire 221 Factory, and there will always be people who gossip or dislike each other.
It would be easier to say if you have the skills.
Experts like Lao Guo Lu Guangda are respected by everyone, and no one will slander them.
But if you are the kind of person who does not work but has no results, you will definitely receive some criticism.
More importantly...
These people at the scene are all practitioners in the meteorological field and have been working in related fields for several years, ten years or even decades.
Starting from their "Tao Heart", they are never willing to see that the knowledge they have learned is of no use in the end.
Therefore, this is a battle of self-revenge and an opportunity to prove myself.
If they are afraid of taking responsibility, they will not even step through the door of the base.
The silent but firm choices of many colleagues soon affected Ye Duzheng on the stage, and he suddenly slapped the table:
"Good! Very good! All good!"
"Since no one wants to leave here, let's have a good fight tonight!"
Said.
Ye Duzheng patted the documents in front of him again and said quickly:
"Comrades, everyone should know that meteorological data is highly time-sensitive."
"So now let's make a long story short and ask the team leaders to come forward and claim the documents they need to calculate."
"First, the first group..."
Later, with the assistance of Tao Shiyan and several team leaders.
These documents were quickly distributed to everyone.
Then it took less than five minutes.
The sound of calculations and the crackle of abacus could be heard in the tent.
As the general person in charge of the project, Ye Duzheng also personally performed the calculations this time, and was responsible for the most complex vorticity field.
Vorticity.
This is a concept that is almost as useful as divergence.
However, divergence describes the degree of dispersion of airflow. Generally, positive values indicate airflow divergence, and negative values indicate airflow convergence.
Vorticity can be divided into absolute vorticity and relative vorticity.
Their relationship can be calculated by [absolute vorticity = relative vorticity 2Ω] (where Ω is the angular velocity of the earth's rotation).
This part of the calculation was applied for by Ye Duzheng on his own initiative. After all...
In the previous calculation process, he had stumbled on the three-dimensional space fluid.
At that time, he converted the Cartesian coordinate system into surface coordinates and split the continuity equation into horizontal and vertical directions for calculation respectively.
At the same time, in terms of trace substances, the instantaneous concentration is decomposed into the mean term and the turbulence term based on Reynolds decomposition.
But the actual situation later proved that his idea was wrong, and he underestimated the actual change of the vertical gradient.
In other words...
He had to redesign a model.
Think of this.
Ye Duzheng first wrote an equation on the math paper:
Du/Dt=??(p/p) v?2u
This is the well-known Navier-Stokes equation, which was proposed more than a hundred years ago and belongs to a system of equations that describes fluid conditions.
Stokes among them must be familiar to some students - yes, this Stokes is Xu Yun's cheap mentor in the 1850 copy...
Its boundary condition with respect to u is u=0.
Then Ye Duzheng quickly wrote:
δT=(?T/?t)δt (?T/?x)δx …
δx=uxδt, then
DT/Dt=?T?t ux?T?x uy?T?y uz?T?z=?T?t (u??)T.....
DA/Dt=?A?t (u??)A.....
So the Okes equation can be rewritten as:
Du/Dt=?u?t (u??)u=??(p/p) v?2u.
Write here.
Ye Duzheng couldn't help but pause with his pen.
The above part of the derivation is an optimization form that he came up with a few days ago, which makes up for the shortcomings of his original ideas.
but.....
At this point after the transformation.
Ye Duzheng didn't know how to continue.
That's right.
It is not possible to calculate or derive which value.
But I don’t know how to derive it.
For this reason, he also consulted Mr. Zhu Kezhen in the capital, but even Mr. Zhu could not do anything.
Mr. Zhu just gave an idea of considering nonlinear terms, but Ye Duzheng always felt that there was something wrong with this.
And just when Ye Duzheng was at his wits' end.
For some reason, Ye Duzheng suddenly felt something strange in his ears.
how to say.......
It feels like someone is blowing air into your ears?
So Ye Duzheng turned his head subconsciously, only to face a face that was wrapped up like Mina Yin.
Ye Duzheng:
"?!"
...
Note:
Everything that needs to be changed has been changed, and we will continue to do it every day starting tomorrow, go ahead!