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Chinese college students send self-developed satellite into orbit_我的网站

A |     (ECNS) -- A student satellite team from Harbin Institute of Technology successfully launched its self-developed Lilac-3 satellite into orbit, marking a milestone for a young team involved in independent satellite development.    The satellite was launched aboard a Gravity-1 Y4 carrier rocket from waters near Shanghai at 10:54 a.m. on July 22. Telemetry data was successfully received at 11:41 a.m., confirming the mission’s success.    Lilac-3 features an ultra-flat disk-shaped design, with its main body measuring less than 5 centimeters in thickness. The design allows satellites to be stacked more efficiently during launches and is expected to support future low-orbit constellation deployment.    When the project began, about 70% of team members were undergraduates, with an average age of 22. Most had no previous experience with complete satellite engineering projects and learned new technologies during the development process.    After the first Lilac-3 failed to enter orbit due to a launch failure earlier this year, the team rebuilt the satellite within three months, improving its performance and adding new experimental tasks.    Founded in 2012, this team is the first university student team in China to independently complete satellite design, development and mission management. Lilac-3 is the fourth satellite successfully launched by the team.    (By Intern Liu Shuangjing, Zhang Dongfang)                    。    The 1989 song "Rhythm Nation" by Janet Jackson has a funky/new jack swing-ish beat that encourages dancing, but it also has a special frequency that can cause some laptops, fortunately from the bygone era of Windows XP, to crash, Microsoft developer Raymond Chen said.,Chen, the chief software engineer at Microsoft, reported the problem on his blog The Old New Thing this week. He claimed that the song's frequency coincided with the laptop hard drive's resonant frequency, which is an object's inherent frequency.,The way a glass breaks when exposed to certain noises is similar to how a laptop crashes, Chen asserted, as the sound from the source sends an unseen vibration through the air and onto the glass.,"A colleague of mine shared a story from Windows XP product support. A major computer manufacturer discovered that playing the music video for Janet Jackson's 'Rhythm Nation' would crash certain models of laptops," Chen wrote. "I would not have wanted to be in the laboratory that they must have set up to investigate this problem. Not an artistic judgment.",According to Chen, the manufacturer discovered that Jackson's song also crashed laptops built by its rivals.,"Playing the music video on one laptop caused a laptop sitting nearby to crash, even though that other laptop wasn't playing the video," he said. "It turns out that the song contained one of the natural resonant frequencies for the model of 5400 rpm laptop hard drives that they and other manufacturers used.",Then, manufacturers included a "custom filter in the audio pipeline that detected and removed the offending frequencies during audio playback," and this fixed the problem. Chen added that they likely attached a digital version of a "Do Not Remove" sticker on that audio filter.,However, he expressed some concern that, after adding the workaround many years ago, nobody would remember its purpose.,"Hopefully, their laptops are not still carrying this audio filter to protect against damage to a model of hard drive they are no longer using," Chen concluded.,Chen did not say what kind of sounds caused such a resonance. But that apparently does not matter now, given the transition of laptops and desktop computers to SSDs.,In addition, Chen attached to the post an old educational video from the data center, which demonstrates the effect of sound wave vibrations, namely human screams, on the operation of hard drives in a rack.,By and large, resonance is a physical phenomenon in which the frequency of one object's sound waves and those of another object coincide. This may result in a sharp rise in amplitude. This is why some bridges have previously collapsed.。

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Published on:00:30:14