Back in 1978, I was admitted to Northwestern Polytechnical University.

Chapter 314: Why is Northwestern Polytechnical University's technological development so rapid?

"Good, good, good. Next, the Navy's brand-new destroyers will be equipped with all the new gear from Northwestern Polytechnical University!" The Navy leaders were very satisfied: "We've witnessed this naval battle and know the situation on the future battlefield. Next, our Navy will be issuing tenders to develop the most advanced air defense destroyers. Is Northwestern Polytechnical University ready to bid?"

"Of course, our navigation department has already refined all the technologies," Qin Liang said. "As long as the Navy issues a tender, we are confident that our Northwestern Polytechnical University's design proposal will definitely satisfy the Navy!"

"it is good!"

The original Type 051 was destined to be unable to meet the needs of the navy. The Type 051S, which was improved by introducing the Sea Dart, was completely abandoned during the Falklands War. Everyone knew that the Sea Dart was useless, so how could they possibly introduce such a thing?

Moreover, with Northwestern Polytechnical University now in place, the air defense problem can be solved!

After reviewing the progress of the Department of Aerospace Engineering, the naval leaders were very satisfied and went straight to the Department of Aero Engines.

“Each department has its own building; right now, only Northwestern Polytechnical University can do that,” said Zhang, the naval leader, with emotion.

The campus of Northwestern Polytechnical University has undergone tremendous changes. Buildings have sprung up like mushrooms after rain. Even the Department of Aero-engine Engineering has built a new building. Moreover, there is a dedicated aero-engine laboratory near the building.

This laboratory seems to be occupying the original location of the Dongping classroom.

Back then, Qin Liang tricked the Americans in the classroom at Dongping and got their funding to support the aero-engine department's research and development.

At the time, it was just an unintentional act on his part, but he never expected it to yield results so quickly!

From Chang'an Aviation College to Northwestern Polytechnical University, Professor Wang Hongji served as the head of the Department of Aero-engines until 1980, when he became the honorary head of the department. Of course, this was only a nominal honor; he was still engaged in research and development on the front lines.

When the group arrived at the laboratory, Director Wang, wearing a white coat, came to greet them.

"Everyone, welcome, welcome! Liangzi, you've finally decided to come back."

"Ahem, well, it's not that I didn't want to come back, it's just that the navy and air force forced me to stay in the capital..."

"Yes, I know you're busy. Everyone, you've come at the right time. Our Spey ship modification project has completed all the research and development work. The testing at Factory 430 has been successfully completed, and the engine can stably output 18 megawatts of power..."

Everyone was stunned: "Wasn't it originally projected to be only 15 megawatts?"

"That's right. It was originally designed for 15 megawatts, but because of its excellent design and large margin, the final output power exceeded the limit. As a result, four engines are enough to propel a warship of more than 7,000 tons, and the displacement of the warship can be further increased, with more space..."

Western warships, such as those designed by Britain, are designed to control costs and limit displacement. In contrast, the displacement of Eastern warships depends entirely on the size of their engines; larger engines allow for larger warships.

Navy leader Zhang took a deep breath: "Good, good, not bad. This way, our warships can be more complete. Are there any bigger ones?"

"Of course, we are currently designing a zero-stage compressor for the engine to further increase the pressure ratio and strive to make the output power of this engine reach 20 megawatts."

"Okay, okay, okay!" Director Zhang nodded. "How did you design it? Can we take a look?"

"Of course, everyone come to the computer room. Oh, and you need to change into shoe covers."

The server room was spacious, with the air conditioner blowing cold air. A large octagonal machine was clearly running at full power, with various indicator lights flashing.

"A supercomputer built with Loongson 2?" The naval leaders were stunned, and Qin Liang was also stunned. Is Northwestern Polytechnical University really that wealthy? One department has a supercomputer?

"Yes, this is a supercomputer that can perform hundreds of billions of calculations per second. Our previous improvements were calculated on this computer. In the past, complex fluid dynamics simply couldn't be simulated on a computer because of insufficient computing power. Now, we perform the calculations on the computer and then take them to the wind tunnel, which is many times faster. By the way, many British projects are also calculated here."

In fact, the Spey modification was initially induced by the computer science department of Northwestern Polytechnical University, which led Rolls-Royce to join in the research. At that time, it only had tens of billions of calculations per second, but now it has hundreds of billions of calculations per second, and the British use it frequently.

Qin Liang had an idea. Now we have another means. If the British dare to continue to make a fuss about equipping the crying country, then we will stop all cooperation with them and make them unable to use our supercomputers!

Looking at the aerodynamic analysis of the zero-stage compressor above, Qin Liang felt as if he had forgotten something.

Wait a minute! You're talking about the Spey modification right off the bat? We're doing this for the pulse detonation engine project.

"I've heard that our pulse detonation engine has made progress in the past few years?"

"Yes, last year we successfully simulated the entire process of detonation combustion on a computer. This year we started developing a prototype. Since we have just started development, we are targeting the engine for use in missiles... If you want to see, I will take you to the pulse detonation laboratory."

This large laboratory is divided into many smaller laboratories. The term "small" is only relative to the entire laboratory. Once inside, the interior space is several hundred square meters.

Professor Liu was still leading his students in research when the group entered. One of the students looked up at them and became instantly excited.

"Qin Liang, you're here?"

"Ding Jun, didn't you... graduate from university a long time ago?"

"Yes, I'm a graduate student! I'm going to get my master's degree at Northwestern Polytechnical University, then my doctorate, and after that..."

"Stay at school and teach?"

"That's right! We were born a student of Northwestern Polytechnical University, and we'll die a ghost of Northwestern Polytechnical University!"

The current students at Northwestern Polytechnical University have an innate sense of superiority. When conducting scientific research at Northwestern Polytechnical University, their technology is among the best in the country and even the world. Staying at the university to teach is what everyone hopes for most. However, the university cannot accommodate so many people, and many will definitely be reassigned.

No matter what organization they go to, if they hear that someone is from Northwestern Polytechnical University, they are almost always immediately appointed as the chief engineer of the project, and can directly lead the research and development.

At this moment, everyone else also put down their work and swarmed around.

"Qin Liang!"

"Senior Brother Qin Liang!"

There are also students who call themselves "senior brother" or "senior brother," which means they are students below the senior year. The fact that these students can do research shows that they are also very capable!
Qin Liang looked at those young faces. The new generation has grown up, and the future of Northwestern Polytechnical University is promising!

"Professor Liu, hello. The naval leaders are very interested in our pulse detonation engine. Could you tell us more about it?"

"Alright, Liangzi, come here, look here. This is the prototype of our pulse detonation engine. This engine doesn't have traditional components like compressors and turbines, so its structure is simple, its thrust-to-weight ratio is high, and most importantly, its cost is low. You could say this engine is a dream engine..."

Nothing else matters; what the naval leaders value most is low cost. They initially thought this brand-new engine would be very expensive, but now it seems it might be cheaper than a rocket engine, allowing for large-scale procurement…

Not bad!
The naval leaders nodded repeatedly.

After leaving the pulse detonation engine laboratory, everyone's stomachs started rumbling, and before they knew it, half a day had passed.

"Everyone, I'll take you to the nearest cafeteria for a meal."

"Yes, eating with these students allows us to absorb some of their talent." The naval leaders nodded. Eating in such a scholarly setting was far more meaningful than dining at a fancy restaurant.

It was peak dining time, and the students in the cafeteria were queuing up in an orderly fashion to eat.

Beep, beep...

Soon, the naval leaders were drawn to the strange sound. Looking around, they saw that each food serving window had a machine about the size of a shoebox with a digital display showing various numbers. Students would insert a card into the machine, and then the chef inside would press a button. After a series of beeps, the card would be removed.

"What... high technology is this?"

Why is nobody using the usual cafeteria meal tickets? Everyone's using these cards! I can understand the stainless steel tray, but I really don't understand these cards.

"Currently, IC meal cards are still contact-based. It will be even more convenient when they are developed into contactless systems in the future."

"IC?"

"An integrated circuit card, you can think of it as a card with an integrated circuit inside, which can store various data. At Northwestern Polytechnical University, this system has been fully implemented."

Qin Liang was aware of this; the relevant departments had been studying it when he left before the Lunar New Year, and now it was finally in use. "After students arrive at school, they can store their money, school subsidies, and so on, in this card to avoid loss. At the same time, it also avoids some of the drawbacks of using meal tickets when getting food in the cafeteria."

Using meal tickets instead of cash is to prevent cafeteria staff from embezzling money and putting it directly into their own pockets. However... this also has its problems. The chefs serving the food can also put the meal tickets in their pockets and then sell them to some students they have good relationships with later.

To completely eliminate this problem, we need to use meal cards!

Meanwhile, all other purchases within the campus are made using this card, and scholarships and similar payments are also processed through it, which helps prevent potential embezzlement by those who handle money.

Northwestern Polytechnical University (NPU) is the first in the country to use this type of card. Of course, this is just a small project jointly developed by the Department of Electronic Engineering and the Department of Computer Science. The replacement of all cards for students is free. Later, when other organizations purchase these cards, NPU can profit from them.

"What if I lose this card?"

"Report it lost!"

What if the device was stolen before it was reported lost?

"For small amounts, like getting food in the cafeteria, you can just swipe your card, but there's a limit, like a maximum of one yuan per transaction. For larger payments, you need a password. Unless it's stolen by an acquaintance who knows the password, they can't steal large sums of money. But if the transaction record can be found, the case can be solved in no time."

If someone steals money and spends it without leaving a record, the case becomes much more difficult to solve. Therefore, the advice from later generations is to always bring cash when going to a massage parlor and never use mobile payment, even if it's been several months, as you might still be investigated.

The so-called "why can't I withdraw my own money?" means I can only withdraw cash; I can transfer it directly through a bank. As long as the card doesn't have a limit, I can transfer freely.

The naval leaders had mixed feelings. They thought, "Even just having a meal in the canteen can broaden our horizons!"
The navy doesn't need it internally, since meals are free, but this system could be promoted in many places across the country to avoid a lot of internal corruption problems.

What would you all like to eat?

"Hmm, this shredded pork with garlic sauce looks good."

"Braised eggplant is also very good!"

Carrying their stainless steel plates, everyone found a place to sit down. Many leaders deliberately carried their plates and sat among the students so they could listen to their discussions during the meal. These students were not afraid of the leaders' authority; students of Northwestern Polytechnical University should have this kind of pride!
"Students, which department are you from?"

"Computer Science Department."

"Oh, Northwestern Polytechnical University's computer science department is top-notch in China. Did you do any research during your studies?"

"We're researching artificial intelligence."

"What?"

"It's about making computers think like humans."

"How is that possible? Don't computers only work according to programs?"

"That's right, computers used to work like that, but things will be different in the future. Our Computer Science Department at Northwestern Polytechnical University is going to research something completely new, something that will allow computers to think for themselves. Just imagine, in the future, when unmanned aerial vehicles take to the skies, you won't need to give them detailed instructions. Just give them a task, and they will choose their own route, fly autonomously, and even handle any unexpected events that occur along the way..."

The naval leader didn't even eat, his eyes wide open. Could this really be happening?
"Yes, the most amazing thing is that it didn't know how to deal with it this time, but it learned how to do it by observing how other aircraft do it..."

Is this... am I sure I'm not listening to someone bragging or talking science fiction?

the other side.

"Which department are you from, students?"

Department of Space Engineering.

"What are your research areas? Cough cough, don't look at me like that, I'm not a bad person."

"No, we can't just say that. Our research project is confidential; we need the teacher's permission, or..."

"Or what?"

"Qin Liang agrees!"

"Liangzi, come here!"

Qin Liang could only bring the tray over.

"Can we talk now?"

"Yes, we work in satellite positioning."

"How's this project going?" Qin Liang was also looking forward to it.

"The project feasibility study was completed last year, and satellite construction has already begun this year. It is expected that the satellite will be completed by the end of the year."

"Did you get the atomic clock?"

"Yes, the same atomic clock supplier for the American GPS satellites sold us. We paid a lot of money for it, but... we won't lose out. We bought three, used two, and gave the last one to our teachers and students in related majors for research. In a few years, we will be able to build our own."

"Great!"

The country is still developing its economy and doesn't have much money to invest in national defense. Even though satellite navigation has huge market potential for civilian use, the high investment is still beyond the country's means. Therefore, Northwestern Polytechnical University can only develop dual-satellite positioning at present.

However, the preliminary research on technology will not stop. A global navigation system with 20 to 30 satellites will definitely be built. At that time, it will be impossible to buy atomic clocks from the international community. We will have to develop them ourselves. Fortunately, our starting point is high enough!
"It'll be launched by the end of the year, that's wonderful!" Qin Liang's eyes sparkled, his mind already filled with the advantages that the development of the satellite navigation system would bring.

Various precision-guided weapons, long-range navigation for the navy and air force, and civilian vehicle-mounted satellite navigation terminals...

It can be said that satellite navigation has the potential to change the world order!
"No."

"Why?" Qin Liang was taken aback.

"Because...our country does not yet have the capability to launch geostationary satellites."

What the hell!

For ordinary satellites, as long as they can escape the dense atmosphere and don't quickly lose altitude and burn up due to air resistance, that's enough.

Therefore, more than 95% of the satellites launched globally are of this type, with an altitude of only about 200 kilometers. The launch requirements are also very low; as long as the speed is greater than 7.9 kilometers per second and reaches the first cosmic velocity, it is acceptable.

The countless small satellites launched in later generations were also of this kind.

At this altitude, there will still be air resistance, so the satellite's lifespan is not very long. It needs its own engine to push and increase altitude from time to time. When the fuel runs out, the satellite's lifespan is over.

Therefore, slightly more expensive satellites will choose medium orbit, which is above 350 kilometers, where the air is thin enough that the drag is very small.

What about geostationary satellites? The first consideration is that their rotation period is the same as Earth's, completing one revolution in 24 hours. According to the orbital formula, the larger the period, the larger the orbital radius. A low Earth orbit satellite can complete one revolution in 84 minutes, so it would take a day and a night to complete one revolution. Therefore, the orbital radius would be more than 42,000 kilometers. Subtracting the Earth's radius, there would still be about 36,000 kilometers left!
That's right, 36,000 kilometers, which is 100 times the orbit of a typical satellite! This distance is comparable to that of the moon!
The distance between the Earth and the Moon is approximately 380,000 kilometers, and the orbit of a geostationary satellite is about one-tenth of that distance.

If the rocket thrust were large enough, it could launch a satellite to that altitude in one go, but... the East doesn't have that capability right now. Even the two superpowers, the US and the Soviet Union, didn't do it that way; it would be too wasteful.

Launching a geostationary satellite requires two orbital maneuvers.

First, launch a near-Earth satellite, which orbits in a circle at an altitude of several kilometers on either side of the Earth's surface. Then, at a certain point, activate the engine to propel the satellite into a centrifugal motion, thus changing its orbit from a circular orbit to an elliptical orbit, with the Earth located at one focus of the ellipse.

The point where the engine is activated is the perigee, which is still 200 kilometers away. When the satellite flies to the farthest point on the other side of the ellipse, it can reach the apogee, which is 36,000 kilometers away!

If you can't reach it on the first try? Then fly back, and at close range, start the engine again to adjust the trajectory!
If there is no change at the apogee, then it can only fly back and move around in an elliptical orbit. Therefore, after completing the elliptical orbit, it is necessary to start the engine again at the apogee to accelerate the satellite so that it can stay in the great circle orbit.

(End of this chapter)