Chapter 1002 An aircraft carrier was photographed?
With Chang Haonan’s announcement on the stage, the entire Numerical Algorithm and Computational Science Conference reached its climax.
As for the reporting session that lasted for a day and a half...
On the contrary, the attention is not that high.
Nothing else, too professional.
About half of the actual participants of this conference are from the enterprise side, and one-third of them are not professional and technical personnel.
Since Chang Haonan intends to build the conference in the direction of “discipline forward-looking”, the report content is mostly theoretical.
For those who can understand it, it is certainly a rewarding experience.
But let alone the media and enterprises, even researchers in the field of numerical computing, if they are not specialized in the direction of the report topic, are likely to be confused.
?The only thing that was quite topical was probably that Chang Haonan, who was the first to give a report, had to fill in the gaps for Professor Jameson, who was the second to give a report.
From a theoretical perspective, the former demonstrated the reasons why the finite volume method results in oscillation or even calculation divergence when faced with high calculation weight problems, and proposed a feasible solution.
The only problem is that this solution requires solving the corresponding constitutive equation first.
There is no universal format for this equation, and it can only be analyzed on a case-by-case basis.
??As for this process of "finding equations", excluding the unfavorable method of making your own wheels and brute force cracking, the most suitable calculation tool is...
Version 2.0 of TORCH Multiphysics.
It is already a murderous and heart-wrenching level.
Professor Jameson, who came on stage later, almost finished the whole lecture without hesitation.
? He ??originally planned to take advantage of COMSOL''s victory in the competition and promote the FVM computing system he has studied throughout his life to the entire industry and all fields.
result…
Promote, probably it can still be promoted.
It''s just that he may not be the one to promote it...
??As for Professor Harold Huang, although his report on the application of compact high-precision formats did not cause as big a stir as the first two, the setbacks of COMSOL made the business community re-examine the rationality of its past technical routes.
?Hence, he finally felt proud.
Although in the academic circle, it is still difficult to turn around after offending people.
But at least it has re-entered the vision of many funders.
For Harold, who had almost reached a dead end before, this was enough.
? And the entire conference came to an end with the vast majority of people enjoying themselves...
…
For Chang Haonan, the previous conference was an interlude, and what happened after the conference was the main story.
One week later.
Beijing, Tanzhou Measurement and Control Station.
Including Chang Haonan, Lin Senming, Luan Wenjie and others, almost all management and technical personnel related to Ocean One gathered here.
In fact, this satellite, which has gone through many hardships and finally achieved success, had been launched as early as the end of March when Chang Haonan was still busy in the numerical calculation competition.
?According to the plan at the beginning of the project many years ago, Haiyang-1 will be carried on the same rocket as the Fengyun-1D weather satellite, and will finally enter working status after about half a month of orbit adjustment.
However, due to many changes in the research and development direction during the process, especially after the addition of optical/radar sea surveillance test missions, the size of the entire satellite increased dramatically.
So much so that the originally planned satellite platform cannot bear the full load.
Fortunately, the Dongfanghong 4 (5-ton class) launched on this timeline was launched earlier, and the research and development speed was also faster. It was rushed and slowed down all the way. At least it provided a full-state engineering star for the Ocean 1 project.
By the way, it is also considered as a platform test.
?At this time, a bunch of valuable precious equipment must be loaded in one piece.
But the satellite problem was solved, and another trouble followed.
?Ocean One needs to work in a sun-synchronous (SSO) orbit.
In the past, China usually launched satellites in SSO orbits using the Long March 4 rocket at the Jinyang Satellite Launch Center.
But the SSO carrying capacity of the Long March 4B is only a meager 2.5 tons.
Not enough.
Therefore, we had to temporarily change the plan to use Long March 3B for launch in Yuecheng.
The theoretical SSO transport capacity of more than 7 tons is definitely more than enough.
?But theory is theory. Changsanyi has not carried out a solar orbit launch mission before, so it is also a first time.
In short, pulling one hair can affect the whole body.
Almost everything that can catch up has caught up.
After a series of adjustments, the launch time was limited to a narrow window in the last few days of March.
As a result, Chang Haonan himself will definitely not be able to witness the launch process with his own eyes.
Fortunately, there is still a period in between from launch to return and then to work. Chang Haonan is not a satellite designer, he is only responsible for two sets of software systems: satellite and ground.
So, as long as he can be there when the satellite comes into operation for the first time.
That is now.
“Director Luan, according to plan, the satellite has officially entered working status at 3:45 this morning, and the first batch of remote sensing photos will be sent back soon.”
The speaker was Zhang Weiyong, the chief designer of the entire Haiyang-1 satellite project.
“Will the first batch of photos… definitely pass the screening?”
Luan Wenjie asked, turning his gaze to Chang Haonan.
Since the content captured by Haiyang-1 is highly sensitive, it cannot send the imaging results to nearby receiving stations around the world like ordinary remote sensing satellites, and then the receiving stations transmit them to the Beijing control center through ground transmission means. Therefore, the communication window is much shorter. .
According to the satellite-borne screening algorithm, if the photo does not capture the content of interest on the ground, it will not occupy the precious space-to-ground link to send it back.
“This… still depends on luck.”
Chang Haonan explained:
"Aircraft carriers are no better than merchant ships. They rarely follow fixed routes except for ports and straits. A single Haiyang-1 satellite can revisit the same location in the shortest period of 3-5 days. If you are unlucky, it will take half a day in a row. It’s normal to not be able to find the target for a month or more.”
“However, before each photo is transmitted back, the satellite will first send out an inquiry signal. The ground can choose to only accept the information that has been preliminarily screened by the satellite, or choose not to screen and accept all information.”
The reason why it is designed in this way is, on the one hand, to get the bottom of things -
??In case there is a problem with the identification algorithm, at least this satellite can be used as an ordinary ocean remote sensing satellite and will not become scrap metal.
On the other hand, it is also considered that this satellite still has to undertake part of the scientific research mission.
Luan Wenjie naturally understood the meaning of these words:
“So... what we are going to test right away is the state of receiving everything without filtering?”
“That’s right.”
Chang Haonan gave an affirmative answer:
“After all, the satellite has just entered working mode. The focus is still on testing the basic functions of the equipment on it. As for whether the algorithm level is effective... this may need to wait for a while to try our luck.”
“Can’t we go and take pictures of ports, such as Yokosuka or Norfolk?”
A naval leader next to him asked:
“These are places where aircraft carriers are almost permanently stationed.”
“And I remember, Comrade Haonan, you also demonstrated in the previous meeting that the algorithm can identify the special outline of the aircraft carrier under relatively complex background conditions.”
“Photographing the port...of course you can”
?Chang Haonan hesitated for a moment, then nodded:
“But it’s best to be similar to our expected use situation, which is to catch a target on the high seas. If we take pictures of ports, we will lose the meaning of our ocean surveillance system...”
“That’s right…”
?The other party obviously agreed with this explanation.
While a few people were chatting back and forth, time finally came to the planned first communication window.
“Report satellite data!”
?Zhang Weiyong walked to the podium and gave instructions in a deep voice.
Soon, a voice came from the hall of the measurement and control center:
“The self-test of spaceborne equipment and programs is normal, and the data is ready to be returned!”
Then, there was a few seconds of silence.
As Chang Haonan said, this is the first time the satellite reports data.
It takes about 10 seconds.
?But this time, the silence seemed to last a little longer.
"Report!"
The voice of the on-site staff showed a rare hesitation:
“Satellite reports indicate that…there are currently 77,920 kilobytes of data streamed.”
At this point, he even swallowed his saliva before continuing:
“There are 16,540 kilobytes of data stream…valid.”
???”
"efficient?"
Chang Haonan, who had just been inoculating Luan Wenjie, said that he might not be able to take pictures of effective targets for half a month, was a little nervous.
Judging from the result, it seems that I was slapped in the face.
But it seems that he was not beaten.
The people around him were also in a daze because of this unprepared situation:
“Effective means that…”
? Luan Wenjie walked to the podium and looked at the display screen in the distance showing the words 16540 kilobytes/77920 kilobytes:
"You mean...we really photographed an aircraft carrier?"
(End of this chapter)