<story><title>Weapon physicist declassifies rescued nuclear test films</title><url>https://www.llnl.gov/news/physicist-declassifies-rescued-nuclear-test-films</url></story><parent_chain><item><author>M_Grey</author><text>&lt;i&gt;&amp;quot;You can smell vinegar when you open the cans, which is one of the byproducts of the decomposition process of these films,&amp;quot; Spriggs said. &amp;quot;We know that these films are on the brink of decomposing to the point where they&amp;#x27;ll become useless. The data that we&amp;#x27;re collecting now must be preserved in a digital form because no matter how well you treat the films, no matter how well you preserve or store them, they will decompose. They&amp;#x27;re made out of organic material, and organic material decomposes. So this is it. We got to this project just in time to save the data.&amp;quot;&lt;/i&gt;&lt;p&gt;That&amp;#x27;s... incredible. Then it sounds like they used a DNN or something similar to analyze the rate of fireball expansion in the films to refine their earlier estimates of yield.&lt;p&gt;What a beautifully subtle use of tech.</text></item></parent_chain><comment><author>jabl</author><text>&amp;gt; Then it sounds like they used a DNN or something similar to analyze the rate of fireball expansion in the films to refine their earlier estimates of yield.&lt;p&gt;Back in the day, some rather simple models were used to estimate yield based on photographs, see &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Nuclear_weapon_yield#Calculating_yields_and_controversy&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Nuclear_weapon_yield#Calculati...&lt;/a&gt;&lt;p&gt;It&amp;#x27;s actually quite amazing that even with such a simple model, G.I. Taylor was able to estimate yield&amp;#x27;s to within 10% of the official figure for the Trinity device.&lt;p&gt;Just because DNN&amp;#x27;s are terribly trendy doesn&amp;#x27;t mean that every image analysis task is done with them. :) I think that at least with such a crude model as the Taylor one, the model itself will introduce errors that DNN&amp;#x27;s per se won&amp;#x27;t fix. DNN&amp;#x27;s might help the manual drudgery of analyzing each frame of the videos manually though..</text></comment>
<story><title>Weapon physicist declassifies rescued nuclear test films</title><url>https://www.llnl.gov/news/physicist-declassifies-rescued-nuclear-test-films</url></story><parent_chain><item><author>M_Grey</author><text>&lt;i&gt;&amp;quot;You can smell vinegar when you open the cans, which is one of the byproducts of the decomposition process of these films,&amp;quot; Spriggs said. &amp;quot;We know that these films are on the brink of decomposing to the point where they&amp;#x27;ll become useless. The data that we&amp;#x27;re collecting now must be preserved in a digital form because no matter how well you treat the films, no matter how well you preserve or store them, they will decompose. They&amp;#x27;re made out of organic material, and organic material decomposes. So this is it. We got to this project just in time to save the data.&amp;quot;&lt;/i&gt;&lt;p&gt;That&amp;#x27;s... incredible. Then it sounds like they used a DNN or something similar to analyze the rate of fireball expansion in the films to refine their earlier estimates of yield.&lt;p&gt;What a beautifully subtle use of tech.</text></item></parent_chain><comment><author>DelTaco</author><text>Fun fact, SSDs deteriorate faster than HDDs, which deteriorate faster than tape.</text></comment>