Into Unscientific Chapter 544

  Chapter 544 Linkage between the two places, start calculation!

   ".Eat an axe?"

   On the clearing.

   Hearing these words from Sun Jun's mouth.

  Old Guo couldn't help being stunned, and a sense of confusion subconsciously appeared on his face.

   But soon.

  He reacted and asked Sun Junren impatiently:

   "Old Sun, you mean that the radar verification is correct?"

  Sun Junren nodded when he heard the words, pointed to the equipment in Lin Yu's hand, and explained with a slightly complicated expression:

   "That's right, according to the data results of this filter made by Kobayashi, no matter whether it is power spectral density, impulse response or chirp signal, there is no problem."

   "And these are the core attributes of a radar, even for a brand-new category such as Doppler radar."

   "In other words, this weather Doppler radar has fully met the requirements in terms of parameters."

   Hearing what Sun Junren said.

  Xu Yun couldn't help but glance at Lin Yu who was squatting on the ground not far away.

   Matched filter.

   This is an early method in radar signal verification.

   After all, when the early radar was developed, drones had not yet appeared, and it was difficult to get the target into the sky—the feasible ideas were basically airplanes or hot air balloons.

  But the cost of the former is higher, and the latter is prone to leaks if it is a confidential project.

under such circumstances.

  Envelope matched filter came into being.

   Well known.

  There are four kinds of received signals of the radar:

Signal,

   noise,

  Interference,

   and clutter.

   Among them, the signal of noise is also the external factor that challenges the radar receiver the most.

  Because the noise does not carry any required information and is mixed with the useful signal, it will reduce the latter's recognition in disguise and also 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 makes the signal simulate the same amplitude-frequency characteristics, so that a signal with a certain carrier frequency is sent to the radar.

  These signals are different from noise, but can only achieve incoherent superposition.

   belongs to a decentralized state.

  These signals can be processed by various components in the radar, and then some more detailed values ​​can be screened out, so as to achieve the effect of verification and correction.

  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 be made by that 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 should not have entered the country, and there are probably no more than five people in China who have mastered the relevant theory.

  So she is either an overseas student who has just returned from studying.

   Either

Self taught?

  In short, no matter what kind of talent they are, they are rare talents in this era.

Of course.

  Xu Yun's surprise was only fleeting, and his attention was quickly attracted by Lao Guo's next sentence:

   "Old Sun, since there is no problem with the radar, shouldn't we start collecting weather data now?"

  Once Lao Guo said this.

  A needle drop could be heard at the scene.

   Within a second.

  Everyone's eyes locked on Sun Junren at the radar console at the same time.

  And at least half of the onlookers had expressions of anticipation and apprehension on their faces, looking eager to try.

   These onlookers have either participated in the production of radar or are the calculation personnel of the weather center. They are very clear about one thing:

  Radar debugging is not the point.

   Everything they did before was actually for

   Weather data collection!

   Only the meteorological data is collected for this information,

  The base has the opportunity to perform weather simulation calculations, and it is possible to accomplish certain extremely important goals that even affect the overall situation.

  Looking at the expectant and nervous faces in front of him.

  Sun Junren was silent for a moment, nodded, and said to Lao Guo:

   "That's right, in theory, it's time to start collecting data now."

   Hear this statement.

  Old Guo's face remained unchanged, but his left hand quietly clenched into a fist.

this moment.

   It's finally here.

   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 check with the departments again."

   "If they are all ready, then let's officially start data collection. As the saying goes, it is better to hit the sun than choose the day."

  Zhou Cai's expression is solemn:

"clear!"

   Say it.

   Zhou Cai turned 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 30 meters away from the radar.

   Zhou Cai walked to the phone in a few steps, took out a booklet from his body, and dialed the phone skillfully:

   "Hello, 9527, please help transfer to 503 factory."

   "Yes, it's me."

   "Oh, ok, thanks"

A few minutes later.

   After several phone calls, Zhou Cai closed the booklet, carefully put it back on his chest, and hurried back 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 ready to cooperate with data simulation at any time."

  Old Guo Wenyan patted Zhou Cai on the shoulder, and asked Ye Duzheng beside him:

   "Comrade Duzheng, where are the comrades in the Meteorological Center?"

  Ye Duzheng and Tao Shiyan looked at each other upon hearing the words, with extremely solemn expressions:

   "Guo Gong, don't worry, there are a total of 37 people in the weather center, all of them are in place today, and they are ready to fight at any time!"

   Describing data calculation as a battle, it can be seen that Ye Duzheng is excited at this time.

   In a sense.

   This is the battle of shame and proof for the weather center.

  If there is sufficient data, it is impossible to calculate the short-term weather trend in the future

  Then there is really no need for the Meteorological Center to exist—at least Ye Duzheng himself thinks so.

  Seeing that every department is in place.

  Old Guo, who had been authorized by the organization before today, no longer hesitated, and said decisively:

   "Very good, since you are so old, let's turn it on!"

   Pata—

   The voice just fell.

  Sun Junren decisively pressed the main control button of the radar.

   After a while.

   buzz buzz —

  The weather Doppler radar, which was on standby, sounded the start sound again.

   But this time, the radar no longer turns left and right as before.

   Instead, he raised his head slightly, and the two X-band intersecting protrusions slowly moved towards the sky.

at the same time.

  In the microscopic world invisible to everyone.

   Pulse electromagnetic waves of special frequency began to spew 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 over the atmosphere at a speed close to the speed of light, and interact with the atmosphere in various ways during the propagation.

  For example, non-spherical particles scatter circularly polarized waves, resulting in depolarization.

   Another example is the scattering of incident waves by the ionized medium formed by the non-uniform refractive index structure of air and lightning discharge.

as well as

  The water vapor condensation in the atmosphere scatters and absorbs the radar emission.

   That is.

  The movement of the scattering target in the scattering volume produces the incident wave.

Doppler effect.

  Five seconds later.

   Whoosh—

  There was a very light sound coming from the metal box of the storage system, it looked like some kind of disc started to spin at a high speed.

   Another fifteen seconds passed.

   Various values ​​began to appear on the screen in front of Baozheng.

  0.5657959

  0.51635742

  1.44470215

  1.52709961

  2.31811523

  5.9765625

at the same time.

Da da d

  The delayed storage device and the dot timer beside the storage device also quickly began to output content.

  See this scenario.

  Ye Duzheng, who had been waiting here for a long time, took several subordinates, and quickly collected the notes and passed them to the telegram team in several other tents.

  Dididididi—

  The telegraph operator began to send the telegram with the speed of an eagle's hand, and Zaun will be the king in future generations.

   And at the same time as the telegram was sent.

  Institute of Computer Science, Chinese Academy of Sciences.

   Telegraph mail room.

  Wu Jikang, then deputy director of the Computer Institute, was standing by the receiver, staring solemnly at a printing device in front of him.

  According to the original plan.

   Today Wu Jikang has a key meeting to attend, which is related to 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 voluntarily turned down the meeting and chose to stay in the institute.

  Firstly, the components of weather Doppler radar are quite special, involving the storage device of 109 aircraft.

  Although the 109 armored machine is only half completed, and the organization has decided to reassemble a new device.

  But as the person in charge of the research and development of the 109 machine, Wu Jikang still really wants to know whether the storage module can operate normally—after all, this kind of actual combat has never had the opportunity to encounter it before.

  The second is.

  If the meteorological Doppler radar can really obtain the expected data, then computer estimation will inevitably assist the simulation in the future.

  So no matter whether it is emotional or reasonable, Wu Jikang must pay attention to the progress of this project today.

  Why haven't you come yet?

   Just when Wu Jikang was in a daze, the telegraph operator beside him suddenly raised his voice:

   "Director, the telegram is here!"

  Wu Jikang quickly recovered and looked at the equipment.

as expected.

   At this time, a brand new telegram has begun to be typed on the telegraph machine.

   And different from the previous cable about Doppler radar.

  This time the 221 factory sent pure weather data, there is no need to keep it secret.

  The content of these data is not encrypted too much and can be interpreted directly.

   So fast.

  A large amount of data was gathered into Wu Jikang's hands.

  Wu Jikang quickly took these data to the computer room on the same floor, which is a warehouse with an area of ​​more than 100 square meters and a computer No. 104.

  The main body of the 104 machine is more than 60 square meters in size, and the display screen is about 50 pieces, which is about the same size as the tablet of later generations.

   Right now.

  In front of more than 50 screens, there is a computer operator with a formal expression. There are men and women, all in their twenties.

  They are the first batch of graduates in China, that is, the 58th grade computer major graduates, and the graduate school is the University of Science and Technology of China.

  If Xu Yun can fly here and have a fight 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 of the future.

   "Xiao Lin, Xiao Wang, Xiao Chen, come and send me some data!"

  After entering the computer room with the first batch of data.

  Wu Jikang walked quickly to the team leaders on the front left, distributed their respective data, and told everyone:

   "Everyone can start importing data after getting the manuscript. Your task is of great importance. Remember to be cautious and never make mistakes! Do you understand?"

  Unanimous answers quickly sounded from the audience:

"Understood!"

  Wu Jikang still had a stern face, looking very serious.

   Actually.

  Considering that there is a lot of data entered this time, if there is an error in individual data, it will not affect the final result too much, so a 3% error tolerance rate is also given.

  However, Wu Jikang did not tell the operators about this, fearing that they would have accidents due to relaxation.

A few minutes later.

  Each operator got the corresponding data in their hands and started to import.

   Mentioned earlier.

  Lao Guo and the others originally collected more than 500 sets of data, but after Ye Duzheng's calculations, they found that these data were not enough.

   To complete the weather simulation, it must be 100,000 times more.

  That is to say, there are more than 50 million sets of data required.

  However, this is only the data required for calculation, and the workload of importing is not so much.

  Because after going through the two levels of electrostatic analysis and X dual-band, these data will be classified into a more standardized interval:

  This interval is refreshed about once an hour, and the same values ​​will be superimposed and directly recorded through the electrical signal of the photoelectric conversion element.

   Therefore, the amount of data passed to Wu Jikang and the others that needs to be imported manually is far less than 50 million sets.

  Take Rabbit's first weather Doppler radar as an example.

  The first meteorological Doppler radar model in China is called 714SD. It collects as many as 14 million sets of data at a time, with a cycle of 15 minutes.

  However, when actually calculating, the electric conversion element filters out 98% of the identical values.

  So the data that really needs to be manually imported is only a few hundred thousand sets—note that importing and calculating are two different things, and the actual calculated data is still 14 million sets.

  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.

  Now there are more than 50 people in the computer room, and each operator actually needs to enter about 30,000 sets of data.

  True 30,000 per day.

   Then soon.

  Many operators began to input data.

   "The temperature is 26.7℃."

   "Humidity 27%"

   "Meridional Wind 18.5m/s"

   "Diffuse radiation 220W/m^2"

   Mentioned a long time ago.

  It is different from the WRF, WRF/Chem, WRF-CMAQ and other models used to calculate the weather in later generations.

   Meteorology at this time was still in a very primitive stage.

   Therefore, even if there is a lot of data, it is still only possible to predict by solving the atmospheric equation.

   That is to say, grid the surface of the earth, and then interpolate the values ​​of each meteorological element to obtain the value at a certain time 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 is mainly to fit various data into more accurate parameters.

   In the words of later generations, it is.

  Processed into semi-finished products?

Of course.

  Although technology is relatively backward in this era, it is after all separated from the early modern history.

  In addition, the computer institute is at least one of the most advanced technical centers of the rabbits, so at this time, the 104 machine is not so primitive that it is particularly miserable.

  At present, although the 104 machine is still out of the limitation of not understanding the equation, the algorithm it uses. Or the idea is actually quite special:

  The time resolution is 1 hour, covering 6 layers of vertical height, and the decoder has only two levels.

   More critically.

  Its mathematical background mechanism comes from the Institute of Mathematics led by Mr. Hua Luogeng.

   That's right.

  Hua Luogeng.

  So although it is still a brute force calculation.

  But in the case of sufficient data, the simulation of the 104 machine is quite smooth.

that's all.

   At regular intervals, a batch of data is sent from Factory 221 to the Computer Institute.

  The operators of the computer institute import the data, and the 104 machine uses the computing power like a classic car to slowly produce the results.

  Eight hours later.

  A data result with a thickness of five centimeters was officially released.

  The original scattered atmospheric particle data is classified into many more detailed models such as parameters in each time domain, wind field, pressure field, density field, etc.

   Immediately after.

  The data was encrypted and sent back to Factory 221, and finally came into the hands of Ye Duzheng and Tao Shiyan.

   So far.

  The entire meteorological deduction has reached the last link.

   That's the Weather Center's

  Manpower correction and derivation.

   "Comrades."

  In a large temporary tent.

  Ye Duzheng and Tao Shiyan glanced at the many colleagues in front of them, and looked at each other, only to hear Ye Duzheng say:

   "A week ago, our calculation results unfortunately failed because the magnitude of the data was not enough, and we underestimated the mystery of nature."

   "But today, we have more magnitudes of data, processed by computer, and summarized into this parameter file in front of me."

   "Originally Mr. Zhu Kezhen from the capital proposed the idea of ​​handing over this document to the Capital Meteorological Bureau, but I rejected it—this is the opportunity for our Meteorological Center of Factory 221 to avenge its shame, and no one can compete with us!"

   "For this reason, I also issued a military order in front of the factory leaders. If the calculation is wrong again this time, including me, everyone involved in the data derivation will immediately report to the animal husbandry sideline team!"

   Say it.

  Ye Duzheng looked around the scene, his tone eased slightly, and he continued:

   "Of course, comrades who have objections to this can quit the next calculation task now."

   "The members who quit can continue to work in the weather 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 now."

   This is over.

  The scene instantly became silent, as if the breath had frozen.

   But in this dead silence.

   But no one stood up from their positions and left.

  Everyone at the scene had a fire burning in their hearts.

   This fire is not anger, let alone grievance.

  It's the pure urge to prove your worth.

   During the past few days.

  Although they were not punished in the factory, the members of the meteorological center have heard some rumors.

no way.

   After all, there are tens of thousands of employees in the entire 221 factory, and there will always be some people who talk badly or don't like each other.

   It's okay if you have the ability.

  Experts like old Guo Lu Guangda are respected, and no one will slander them.

   But if it is the kind of person who does not work but has no results, he will inevitably receive some criticism.

   More critically.

  These people on the scene are all practitioners in the field of meteorology, and have been working in related fields for several years, ten years or even decades.

  Starting from their 'Tao Heart', they never want to see that the knowledge they have learned is useless in the end.

  So this is a battle of self-reproach and a chance to prove yourself.

  If they are afraid of taking responsibility, they will not even step in the gate of the base.

  The silent but firm choice of many colleagues soon infected Ye Duzheng on the stage, who suddenly slapped the table:

   "Good! Very good! Everything is good!"

   "Since everyone is unwilling to leave here, let's count it out tonight!"

   said.

  Ye Duzheng patted the document in front of him again, and said quickly:

   "Dear comrades, everyone should know that weather data is highly time-sensitive."

   "So now let's make a long story short, please ask the team leaders to come forward and claim the documents that they need to calculate."

   "First group first."

   Then with the assistance of Tao Shiyan and several team leaders.

   These files were quickly distributed to everyone.

   Then it took less than five minutes.

  In the tent, there was the sound of brush calculations and crackling abacus.

  As the general manager of the project, Ye Duzheng also personally went out to carry out the calculation this time, and he was in charge of the most complicated vorticity field.

   Vorticity.

   This is a concept similar to divergence.

  However, the divergence describes the degree of dispersion of the airflow. Generally, the positive value is the airflow divergence, and the negative value is the airflow convergence.

  The 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 requested by Ye Duzheng on his own initiative, after all.

  In the previous calculation process, he once stumbled in the aspect of three-dimensional space fluid.

  At that time, he transformed the Cartesian coordinate system into surface coordinates, and split the continuity equation into horizontal and vertical directions for calculation.

  At the same time, in terms of trace substances, according to Reynolds decomposition, the instantaneous concentration is decomposed into mean value item and turbulent flow item.

   But later the actual situation proved that his thinking was wrong, and he underestimated the actual amount of change in the vertical gradient.

   In other words.

  He had to redesign a model.

  Think here.

  Ye Duzheng first wrote down an equation on the arithmetic paper:

  Du/Dt=(p/ρ)+vu

   This is the well-known Navier-Stokes equation, which was proposed more than a hundred years ago and belongs to a system of equations describing fluid conditions.

  Stokes among them must be familiar to some students—yes, this Stokes is Xu Yun's cheap tutor in the 1850 copy

   Its boundary condition on u is u=0.

   Then Ye Duzheng quickly wrote:

  δT=(T/t)δt+(T/x)δx+…

  δx=uxδt, and then

  DT/Dt=Tt+uxTx+uyTy+uzTz=Tt+(u)T

  DA/Dt=At+(u)A

  So the Navier-Stokes equation can be rewritten as:

  Du/Dt=ut+(u)u=(p/ρ)+v2u.

   Write here.

  Ye Duzheng paused at the tip of his pen.

  The above part of the derivation is an optimization form he came up with a few days ago, which makes up for the lack of his original thinking.

but

   It is the step after the variant.

  Ye Duzheng didn't know how to continue.

   That's right.

   It is not calculated or cannot deduce 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 couldn't help.

  Old Zhu just gave an idea of ​​considering non-linear items, but Ye Duzheng always feels that this is a bit problematic.

   And just when Ye Duzheng was at a loss what to do.

  For some unknown reason, Ye Duzheng suddenly felt something strange in his ears.

how to say

  As if someone was blowing wind into his ear?

  So Ye Duzheng turned his head subconsciously, and he just met a face wrapped like a mummy.

  Ye Duzheng:

Note:

  Everything that needs to be changed has been changed, starting from tomorrow, I will continue to do it day by day, go ahead! !

  (end of this chapter)

Chapter end