'Excerpts' 1. In addition to being truth-seeking and successful, scientific research can be a value if it can prove that something is wrong, that is, to do the right thing and to eliminate some wrong things, we should Try to put it in the same position.
2, as long as the time spent on one thing more, and the other must spend some time is less, so there is no way to balance what it can only guarantee that it is guaranteed to do everything It makes sense that spending time is not a waste of time and that's all. It is also important to popularize science so it will take some time.
3, now the child may have grown up want to be a star, or idol, this is not necessarily out of a hobby, just want to stand in a position of worship, from this perspective, this is science A loss of value orientation.
4, Indoor positioning will be the next trend of navigation, but indoor is not yet a 100%, can adapt to a variety of environments a particularly effective solution, which is now our focus.
5, we are now studying 'seamless navigation', hoping to achieve seamless indoor and outdoor convergence.The main difficulty now is to reduce costs, adapt to the environment and other issues.We have done a set of such a system on the phone, but Still in the stage of technical verification, there is still some distance from large-scale applications.
6.In each country, there is no PK in the satellite navigation system, but more work on compatibility and interoperability, especially in the civilian areas. In civil usage, Beidou satellite precision can reach millimeter level.
'text'
Last year, a science fiction video by BeiDou Navigation Satellite Positioning System, taken by the Chinese Academy of Sciences, became popular online and Xu Ying was the talkative beauty anchorwoman in the video after 80. She has since become very busy: besides doing research and bringing students, To squeeze out time to do popular science lectures for Xu Ying, the concept of rest days have long gone, let alone shopping shopping.
Even so, she still does not want to give up this extra 'work' for science, making it an important mission for children to be interested in science, treating scientists less than celebrities, growing up to be stars, idols instead of The dream of becoming a scientist is what she thinks is a loss of the scientific value orientation. "Now science is to avoid being unable to recruit students after thirty years, for example, when children grow up they do not want to come This thing, it can not recruit students, this is what we do not want to see. "Xu Ying said.
It is understood that Xu Ying or CCTV scientific challenge program "witty" guest, she believes that such a lively and interesting video form can make science interesting, no longer dull boring, thus stimulating public interest in science.
In fact, embarked on this road of scientific research, for Xu Ying is not an 'active pursuit' of the process, but a very natural choice after graduating from college, Xu Ying want to continue their studies, obtained the Beijing Institute of Technology signal and information Under the guidance of the supervisor, he started to contact the first phase of the 'Beidou Second Generation'; after graduation, he naturally entered the work of the Chinese Academy of Sciences and engaged in the Beidou Navigation Satellite Positioning System; and six years later, Was hired as a doctoral tutor, a Chinese Academy of Sciences doctoral tutor.
Beidou system for questioning the outside world in the accuracy and reliability as GPS system, Xu Ying will be relentless to explain.
Positioning is not accurate but also to see the specific conditions.Directly say that it is not accurate, it can only be based on a statistical result.Satellite navigation is such, the satellite is far away from us, so when it comes to the ground itself The signal is very weak, it is submerged in the noise inside. We have to coherently accumulate in this way, its signal to noise ratio compensation back, and then be able to correlate it in order to signal it to detect and estimate So it is actually very easy to be disturbed and obscured, which is normal, for example, you are indoors, you will not receive satellite signals.Xu Ying explained, 'This is the natural vulnerability of satellite navigation systems. But this is the same for all satellite navigation systems. GPS, BeiDou, GLONASS and Galileo are the same, because the big principle is that you can not say that you can not get a dipper Signal, Compass good, so to say it is not good.
She also cited a more vivid example: this is equivalent to saying that there is a chef to give you a plate of twice-cooked pork, you can not eat the smell of fish-flavored pork, and then said that the dish is doing bad. Can not be evaluated from this perspective.
When it comes to indoor positioning, Xu Ying said this will be the next trend in navigation development, and this is exactly the project that Xu Ying led the team to study: seamless navigation, is hoping to be able to do indoor and outdoor seamless.
The current study has two major problems to be solved: First, how to do low-cost. 'Everyone to buy a very expensive terminal, the indoor can be positioned, may not be appropriate.' Xu Ying said the other is how Adapt to a variety of complex environments, to achieve adaptive problems.
According to Xu Ying revealed that the team has done a system on the phone, but is still in the stage of technology verification is still some distance away from large-scale applications.
The following is Netease's interview with Xu Ying part:
Netease Technology: We know that you participated in the CCTV science challenge program "witty", for you, what is the biggest attraction? In the science of communication what kind of innovation?
Xu Ying: I think the biggest attraction mainly depends on what is said to be brought together all kinds of top technologies of artificial intelligence in our country. Because artificial intelligence was especially hot these two years, although I did not do artificial intelligence myself, I was quite interested in artificial intelligence of.
In addition, I feel that science has spread in recent years, but the fact is that the people in the country still pay great attention to it. But where do we all feel the most painful point of scientific communication? It is to find a particularly good form because, after all, science is relatively boring To raise the general public's interest in science, it must find a very good form to stimulate public awareness of science.
Netease Technology: We also read a lot about your report, after (Beijing Academy of Sciences) 'Beidou navigation satellite positioning system science video', you are invited to popularize science knowledge everywhere. Everyone is quite concerned, how do you balance yourself The relationship between research projects and lectures? Time processing is what?
Xu Ying: Time is always limited, you spend more time on one thing and less time on the other. Just as each year our new employees have a training, I sometimes give them Talk about what the road to growth, where they always ask, because in fact we have a lot of girls here, about half the proportion of the most asked girls is a topic, how to balance work and life, just like This is actually similar, that is how to balance your time.
At that time, I still thought that this thing was in fact not balanced. In other words, as long as we spent more time on one thing, and on the other thing, it would take less time and there would be no way to balance it What can be guaranteed? Then make sure that everything that you think you did makes sense, and that the time you spend is not wasted, and that's it - so there's no way to balance it.
It's really going to take you some time before we get back to getting started with this topic, but it's also important to get the science popularized and it will take some time.
Netease Technology: But many scientists will say that research needs to stop and spend a lot of time doing scientific research.
Xu Ying: In fact, I think this view should be changed because now although many scientists may not do science, do not do science popularization of science, we can guarantee that you spend 100% of the time in scientific research. not necessarily.
He still has a lot of other social activities, there will be many other social activities, there will be a lot of things that do not seem to have much to do with scientific research, for example, to do a lot of financial work, the end of the funds to review, to declare Project, there are many coordinated things in this process.It may not be exactly the same as what we call the scientific research sinking in the traditional sense.
So I think this thing is very normal. You see now, for example, you say that you are like Shi Yipong and Pan Jianwei. They actually have very, very much social activities, but this does not really affect their scientific achievements.
Netease Technology: Beidou satellite positioning effect analysis is an important part of navigation system performance evaluation, but many factors affect its precise positioning, how to achieve more accurate positioning?
Xu Ying: Because positioning is not allowed to see the conditions. Direct up to say that this is not allowed, can only be based on a statistical result. Because the satellite navigation is so, the satellite is far away from us, so when it is to the ground The signal itself is very weak, it is submerged in the noise inside.
We need to compensate for the signal-noise ratio by coherently accumulating it before we can correlate it so that it can be detected and estimated, so it is actually susceptible to interference and obstruction It's normal, for example when you are indoors, you will not receive satellite signals.
This is the natural vulnerability of a satellite navigation system, but it is the same for all satellite navigation systems. GPS, Dipper, GLONASS and Galileo are the same, because the big principle is that you Can not say that in the room are not received Beidou signal, Beidou poor, so to say it is not good.
This is equivalent to saying that there is a cook to give you a plate of twice-cooked pork, you can not eat fish-flavored pork flavor, I think this dish is doing bad. Can not be evaluated from this perspective.
Netease technology: whether there is a new evolution of technology can make up for this disadvantage?
Xu Ying: Indoor positioning everyone is doing now, it will be the next trend of navigation. Indoor positioning now a bit like the satellite navigation out of the outdoor positioning before that scene. Because before the satellite navigation, outdoor positioning, there are actually many However, after satellite navigation, it basically solved the problem of locating more than 90% of the outdoors, so it has its own advantages and is widely used.
Indoor There are many different technologies nowadays, such as Bluetooth, Wi-Fi, UWB, mobile network, inertial navigation, vision, PDR, and many others, including Zigbee. But every technology may have its own limitations, and its, for example, to give priority to the deployment of nodes, or in a particularly large number of people when its positioning accuracy is poor or inertia guide that you cut off time To school it once, otherwise it will drift, similar to this.
So indoor is not yet a hundred percent of all, can adapt to a variety of environments a particularly effective solution, which is one of the focus of our research.
Netease Technology: So your current research direction is about indoor precise positioning?
Xu Ying: Yes, we call it seamless navigation, is hoping to be able to do indoor and outdoor seamless.
Netease Technology: The difficulty of this project or the problem where, or to what extent to what extent?
Xu Ying: Now the main difficulties and problems lie in saying that one is how to achieve a low cost, for example, to buy an expensive terminal for everyone, indoor positioning may not be appropriate. Of the sensor, how to integrate it, this is a difficult task because the sensor on the phone some of it may be relatively low precision, and the accuracy of scientific experiments than impossible, because it is after all the cost here .
And the other question is how to adapt it to a variety of environments. It is possible that it is possible to do somewhere in this area, say give me a condition, head up in this building, do it well, after a long period of debugging or What is possible, but then take it to another building inside, it is not necessarily good to use, that is how to adapt to the environment can have a self-adaptive, this is the more difficult place. We are on the phone to do such a system, is to use the phone's sensor to do such a job, indoors.
It is now at a stage of technical validation that may be a long way from large-scale applications.
Netease Technology: Each country in the precise positioning of the key elements of what?
Xu Ying: You said there are PK, there are, but more is compatible and interoperable .In fact, every country is the first to build satellite navigation and positioning system to ensure our own national military safety and reliability, which Is the most important thing. Of course, you have to have it at this time. This is an important point. In fact, more people in the community now do a lot of compatibility and interoperability. For example, every year there will be such compatibility and interoperability Assembly, going to discuss with each other, between our signals should be compatible.
What kind of benefits can this bring? In other words, my cell phone may receive GPS, receive BeiDou, receive GLONASS, and receive Galileo, so that the accuracy or reliability of navigation and positioning can be achieved For example, now there will be a station to a downstairs, because this building may be high, blocking my side of the satellite, probably from the half of the satellite are not received, the positioning accuracy may be poor, but If you say that the sky of the satellite, that is, you said GPS24 stars, Beidou 35 stars, the number of satellites more, then I can now receive more stars, in this case, the satellite is more than enough, but also to navigate Positioning.
Netease Technology: What factors affect the accuracy of what?
Xu Ying: This is derived from several factors, one is the configuration and layout of your constellation. Because the final positioning accuracy of satellite navigation is UERE multiplied by the DOP value, a UERE is a ranging accuracy, multiplied by DOP value is the distribution of satellites, so closely related to the satellite distributed.
UERE is the measurement, the measurement of this thing and what is related to several things ... One is that the satellite launch signal itself is what the accuracy of this signal is like the signal above is carrying the time information, the time is not accurate Quasi, is the satellite atomic clock (sound) this kind of things are not allowed, and then what kind of signal format, the different signal format obtained by the measured Kelame Luo lower bound (sound) may be different, for example, it There are a variety of modulation methods, BPSK modulation, BOC modulation, may be different. Then down is the signal is not a frequency, the frequency of time after the spread of it in the atmosphere of the propagation characteristics are not the same, so And the frequency of what are also closely related, so in general, and all these factors are related.
There is also a very important point to include is that in addition to this one satellite, not a good many satellites, the degree of coordination between these satellites is what, it is also closely related.
Netease Technology: Beidou satellite in civilian areas, high-precision can reach what extent?
Xu Ying: civilian high-precision it is now able to reach the millimeter accuracy. Of course, it is limited, can not be very fast moving objects. Because there is a civilian application scene called bridge deformation detection, is similar to this It puts a receiver in there and then corrects its error differentially, and then does this observation for a very long time, where it can be accurate to the millimeter for long observation times.
Netease Technology: 'The application of satellite navigation and positioning system is only limited by the imagination', what are the application scopes of Beidou satellites explored in our country at present? What new fields need to be explored?
Xu Ying: satellite navigation and positioning system to provide us with a basic one of the time and space information, we call space-time basis.And space-time reference is all the information network can interconnect a foundation.So that is to say, its application is very, very For example, we think power system may not be related to satellite navigation at all, but in fact, satellite navigation system to do the power time is to give it a time synchronization, so that the power system, for example In the peak of electricity, to have a more reasonable power distribution, is similar to this, we all feel that power has nothing to do with satellite navigation.
There are financial systems, such as the time, when the time of the financial settlement, the time difference to go out in milliseconds, in fact, the amount of settlement seems to be out of tens of millions of dollars this heavyweight, so it is also possible to use the Big Dipper system To do it a precise time synchronization is similar to this, we may also think it does not matter.
Netease Technology: We interviewed a series of scientists in addition to hoping to achieve popular science, but also want to let science popularize, science has become a fashion thing.What do you think of the current scientists and celebrities so different treatment?
Xu Ying: First of all, this social phenomenon, of course, we very much do not want to see, when we were young scientists feel that it is a very honorable thing, so write, my ideal to be scientists. Now the children actually do not like this Perhaps their ideal is that I grew up to be a celebrity or I wanted to be an idol, not because of hobbies, because he did not mean I wanted to be an actress or I wanted to be a singer or I wanted When he is pure, he wants to be in a position of adoration, so I want to be the one, so in some ways it is science, or is it a loss of scientific value orientation, indeed.
But you say, in fact, it is very difficult to make scientists like stars.Why? Children may like celebrities will not like scientists, celebrities look good on the one hand, celebrities do things very entertaining, easy to attract But scientists need people to understand the story behind them, scientists are not entertaining and have limited means of communication, making it hard to attract children.
Netease Technology: So we only science.
Xu Ying: Of course, science is very, very important, and we also mean that science popularization now is to avoid the situation that I can not recruit students in 30 years. Thirty years later, for example, when a child has grown up, Do not want to do this thing, you can not recruit students, this people do not want to see the phenomenon occurred.
Netease Technology: Scientific research is a boring process, it may take a long time and did not get the results you want to confirm, when encountered such a problem how do you solve?
Xu Ying: In fact, when we talk about this kind of value orientation, it is the value orientation of science. Apart from being truth-seeking and seeking success, if we can prove something wrong, in fact it should also be a value. There will be no more people to study this thing, take this detour .That is to do a right thing, and ruled out some wrong things, we should try to put it in the same position.Some items may There are a lot of teams to study, not all the hard work and things you do after the research is done by a team, because there are many subdivided points among them, like this year's Nobel Prize Gravity Wave There is nothing, yes, it is not a person to do, it has a lot of people doing it. Not to say that after he made it, there is no value to do gravity waves, and on this basis, he will certainly There are some unique points, just saying they may not be well known to the general public, but they must still be in his profession, and as long as you have done something, there must be some recognition.
Quick answer:
Netease Technology: Who is your most admired scientist? Xu Ying: Qian Xuesen.
Netease Technology: If you did not choose this area, then what are some other dreams or ideas? Xu Ying: that is when a scientist, I now seem to realize the dream.
Netease Technology: If you mention science, what is your first thought? Xu Ying: rigorous and innovative.
Netease Technology: What do you think most need to do scientific research? Xu Ying: rigorous and innovative.
Netease Technology: If you do scientific research, what is the most difficult? Xu Ying: In fact, the most difficult point to do science is to say, do not know this thing is not correct.
Netease Technology: What is the advice of people who want to be scientists? Xu Ying: To be lonely, or to be able to endure loneliness.