Wan Lei was busy when preparing for the founding of the country. When the country was established and he was sworn in as president, he was free. Because general government affairs were handled by the Executive Yuan and ordinary military affairs were handled by the Military Commission. All Wan Lei had to do was to Daily government affairs were reviewed and filed, and he hired a team of secretaries to take care of those trivial matters, so he was very free.
When Wan Lei is free, he spends a lot of time with his family and students every day. He now has five students and is preparing to accept a few more. Since the beginning of Peking University, Wan Lei often gives lectures in various colleges. , I go to the College of Engineering most often, on the one hand, to educate the younger generation, and on the other hand, to cheer up my wife, because Fu Wei is the dean of the College of Engineering, and after the establishment of Peking University, the College of Engineering was merged into it.
In fact, in the entire Peking University, the most promising ones are the School of Administration and the School of Engineering. The School of Administration trains reserve officials, and the fire is inevitable. The reason why the School of Engineering is as famous as the School of Administration, or even superior to the School of Administration, is mainly because Because the engineering college has the strongest students and teachers,
The College of Engineering consists of science and engineering, chemical engineering, applied mathematics, biological sciences, geological and mineral exploration, metallurgical engineering and other subjects. The teaching content covers applied mathematics, physical principles, chemical principles, biological principles and mechanical engineering. Research directions include civil engineering, shipbuilding engineering, water conservancy engineering, papermaking, winemaking, vinegar, sugar processing, and textile industries.
There are many subjects and heavy academic work. People who are not particularly smart will not be able to enroll, and those who are not particularly hard-working will never be able to graduate. Therefore, the Engineering College is a gathering place for the elite. Every citizen of Beiping Province has to go to the Engineering College. It is a honor to study. If a child can enter an engineering college, the whole family will feel honored.
Those recruited are all elites, and those responsible for education are the elites among the elites. Chongdaotang, which is responsible for high-end scientific research, sent fifteen of the best scientific researchers as professors, and also invited dozens of people from various places who are skilled in various fields. Many veteran craftsmen came to give lectures, and even Wan Lei was one of the honorary professors.
At the same time, the School of Engineering will also issue many small scientific research projects to encourage students and teachers to participate in research and development. Once there are results, they will also be given material and reputational rewards, making the students in the entire School of Engineering work hard to study. In the past, Some unsolvable technical problems were easily solved through collective efforts.
"Today, let's talk about the principle of telegraphy." On the night of February 16th, Wan Lei came to the School of Engineering to give a lecture. He would either not give a lecture, but would talk about the most cutting-edge topics. This also attracted many teachers from the college to come and observe. Wan Lei has become accustomed to this. He shook a piece of paper in his hand that was full of words and said: "Now I have a document in my hand. What should I do if I want to send it to the frontline general? "
"Using a fast horse to deliver a message can cover thousands of miles in one day."
"Sending messages by flying pigeons,"
"Transport by train,"
"Build a beacon tower and use flags to send messages,"
Everyone immediately came up with a plan, but Wan Lei shook his head and said: "These methods are really too slow. This document is not too important. A few days of delay may not matter. But if it is an urgent military situation, then a day of delay will be fine." It may lead to a disastrous failure, especially at sea, where there are ocean barriers, inconvenient transportation, and ineffective information. Therefore, we need to find a new, fast communication method that is not affected by distance and environment."
"Everyone knows that in this world, the speed of light is the fastest, 300,000 kilometers per second. If light can be used to transmit messages, instant communication can be achieved even across oceans. However, with our current technology, it is still impossible It cannot be realized. What I want to talk about now is to use electric current to transmit messages. Electrons can be transmitted along wires. The theoretical speed is equal to the speed of light. It is also the most likely method of communication to be realized in the short term."
"First of all, let's review the knowledge about electrons and electric current." Wan Lei paused, glanced around, and said, "Who can tell you about the generation of electric current and the electromagnetic induction effect?"
The students below immediately raised their hands. Wan Lei just called a female student casually, and the female student talked non-stop. In fact, electricity is also one of the compulsory courses for entry into the School of Engineering. Many people present were surprised. Concepts such as various electromagnetic induction effects and current, resistance, and voltage give me a headache.
"Electromagnetic induction refers to the magnetic effect of electric current. When a current is passed through a wire in a circuit, a magnetic field can be generated; when the wire moves through the magnetic field, it can also generate a current."
"Thank you for your explanation. Please sit down now." When the female student said this, Wan Lei interrupted her, "There is a magnetic field when the power is on, and there is no magnetic field when the power is off. This means that we can have two It is an intuitive and controllable physical phenomenon. When I turn on the power here, as long as there are wires connected to it, and as long as there is an electromagnetic sensor, even if it is thousands of miles away, it can sense the current passing through it at the same time, and it will also know that it is connected here. Turn off the power switch, that’s what it looks like,”
"That's true, but just turning on the power doesn't express the meaning of the words," said a student below. In fact, the School of Engineering now has batteries that can be used for experiments, as well as copper wires, and many current circuit experiments can be done. Students all understand what Wan Lei said.
"Of course, just turning the power on and off once can't express the meaning, but as long as it is turned into a pulse signal, it can convey the message,"
"For example, within one second, I press the switch, then the receiver thousands of miles away will know that the number I want to express is 1. If I don't press it, then, of course, it is simply the sum of 1 It has no practical meaning, but when you combine them, it becomes a string of numbers, which can express the meaning."
Seeing that the students below were all frowning and thinking, Wan Lei added: "Now, let me briefly explain the knowledge of binary. Binary is actually a brand-new calculation method. It has similarities with decimal. Decimal is the When decimals are added to one, the base is ten, while in binary, when two are added to one, the base is two,"
"The reason why we talk about binary is mainly to facilitate the calculation of mechanical language. Machines are different from people. They do not use different symbols to express numbers. There are only two relative states: open and closed, closed and closed. Open can be regarded as 1 , the combination can be seen as, if you want to use this state to express decimal numbers, you have to use base conversion,"
"For example, the number 1 in the decimal system can be represented by the binary 1, and in the decimal system, it can be represented by 1, 3 can be represented by 11, and 4 can be represented by 1. We can try to represent each Divide three seconds into a group, and you can express these eight numbers, that is, 1 is 1, which is 1, 3 is 11, 4 is 1, which is 11, 6 is 11, which is 111."
"Within three seconds, I turned on the current three times in a row, which is 111, which means that if I turn on the current once first, and then turn it on again one second apart, it is 11, which means, and the commonly used Chinese characters are, Around 3,500, when it comes to these eight numbers to mark them, four paragraphs are enough. For example, for the word 'I', assuming its number is 43, then translated into a telegraph code, it is 111,,1,11 Four sections, if you send out a pulse signal like this, you can transmit a word in more than ten seconds, and a simple order can be issued in a few minutes."
"Of course, this is just an idea stage. With mature technology and skilled dispatchers trained, efficiency can also be improved. A document of several hundred words can be delivered within an hour. Now that the theory is over, the focus is still on how to apply it. "Wan Lei stopped to take a sip of water and said below: "If you have any questions, you can ask them now."
"Sir, how do binary operations work and what are the rules of operation?" Someone stood up and asked urgently,
"Binary operations will be discussed in applied mathematics in the future. Now you just need to remember the representation of these eight numbers,"
"Sir, although the two methods of turning on the light can theoretically achieve communication, the magnetic field generated by the current is inherently very weak. How can it be observed? In addition, the wire has resistance, and the current will become weaker as the distance increases. This makes it even more difficult to observe." Another student stood up and asked,
"What you are talking about is one of the technical problems we are facing now. In order to overcome this problem, we must develop highly sensitive electromagnetic sensors. At the same time, we must increase the voltage of the power supply and use materials with smaller resistance as wires. Reduce the loss during transmission, so that the pulse signal can be clearly transmitted to farther places,"
"Sir, telegraphs are connected by wires, and there must be transmitters and receivers on both sides. This means that they can only transmit information point-to-point. This means that if you build a wire, only two telegraph machines can be used, and others cannot Isn’t this too wasteful?” Another student asked,
"Establishing military dedicated lines connecting various places is very important for a country. No matter how much it costs, it is worth it. Compared with the method of urgent delivery by horse, telegraph is still cost-effective,"
"in addition,
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