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Joined 3 years ago
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Cake day: June 26th, 2023

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  • The Department of Homeland Security was just a combination of existing federal bureaus into one entity. What you have to remember and what is noted in the 9-11 report and everyone should read the 9-11 report is that we had evidence of the attacks prior to them occurring, but the problem was inter-agency rivalries prevented the information getting to some central location where you can connect the dots.

    Now it’s not to say that there wasn’t a lot of knee jerk authoritarian reaction to the attacks in the form of the patriot act, warrantless surveillance, legalized torture, and extraordinary rendition. Combining federal agencies into the department of homeland security by comparison seemed pretty mild at the time.







  • Rough surfaces can be more aerodynamic than smooth ones

    “For more than 80 years, the principle of “the surface of an object must be smooth” has been the basic premise of aeronautical engineering throughout the world in order to suppress the transition to turbulence and reduce aerodynamic drag. This premise was based on the results of a 1940 study by Ichiro Tani, a Japanese aerodynamicist who quantitatively demonstrated the relationship between “surface roughness” (an indicator of the state of the machined surface) and turbulent transition, arguing that surface roughness, which was unavoidable with the manufacturing technology of the time, prevented laminar flow from being realized.

    However, in 1989 Tani reinterpreted the experimental data on rough-surface pipes obtained by fluid engineer Johann Nikulase in the 1930s, bringing a new perspective that “roughness may not necessarily only promote turbulent transition and increase fluid resistance.” Inheriting this idea, a research group led by Yasuaki Kohama of Tohoku University experimentally demonstrated in the 1990s that fibrous rough surfaces, which have fine fibrous irregularities on their surface, have the effect of delaying transition under certain conditions.”