> I can put the cuff on my arm and sit at my desk for 20 minutes to be nicely rested and calm, and then take 5 different measurements with a few minutes between each one. ...
Doesn't it take more than a few minutes for one's circulation to return to normal after a BP measurement?
Eh, not really. We measure blood pressure every five minutes (or less) for patients under anesthesia. They're pretty reliable. Of course, they're unconscious, so they can't really anticipate the discomfort of the cuff going up on their arm and react to that, and frankly given that they are being carved open the pain of a cuff is pretty minimal by comparison.
This post, along with the tutorial links it and the comments contain, provide good insights on the topic of caches, coherence, and related topics. I would like to add a link that I feel is also very good, maybe better:
In the 1980s, PT and ET were common. I was working at Bell Labs then, and one of my jobs was to change the time zone (back then it was two words) on the testing machines, as needed. This is stuck in my memory since to change the timezone, you needed to edit the Unix kernel source code and recompile it!
Wasn't there a HN post a few weeks ago, describing how your phone's location can be tracked without anything installed and without leaving any trace on your phone? I think it was an exploit of CSS7 protocol used by networks?
That password should include symbols too! Without symbols, each character is one of 62 values (sticking to ASCII letters and digits). Including symbols makes it much harder to guess passwords of a given length. Even better would be Unicode letters, digits, and symbols, even if you stick to the Basic Multilingual Plane.
Best would be non-text, binary strings. Since I already use a password manager, I don't really need to type passwords by hand. But I do understand most people prefer text passwords that could be entered by hand if necessary.
Except that's exactly what the Mossad will be expecting us to use, for our uber-secure password! By eschewing symbols and binary, we are actually meta-out-smarting their ultimate giga-quantum nuclear crypto cracker.
Or: This is Bob "Dim Bulb" Jones we're talking to. KISS, and maybe we can convince him to upgrade his password to "iwantacoldbeernow".
Sorry, your password does not meet complexity requirements because it does not contain at least one of each of the following: uppercase letters, lowercase letters, numeric digits, nonalphanumeric symbols.
I appreciate this post! I was hoping you would add an inline CSS style sheet to take care of the broken defaults. I only remember one off the top of my head, the rule for monospace font size. You need something like:
But I vaguely remember there are other broken CSS defaults for links, img tags, and other stuff. An HTML 5 boilerplate guide should include that too, but I don't know of any that do.
> It is interesting that no software engineering or computer science course I’ve seen has ever spent any time on CI/CD.
It's hard to fit everything student needs to know in the curriculum. Someone else posted here they had 10 pages of proofs per week, for one course. I would have been fired for assigning so much homework!
I was a CS professor at a local college. My solution was to ignore CS1 and CS2 curriculum (we were not ABET accredited, so that's okay) in the second course of Java programming. Instead, I taught students Maven/Gradle, Git and GitHub, workflows, CI/CD, regular expressions, basic networking, basic design patterns, Spring Boot, and in general everything I thought new programmers ought to know. I even found a book that covered much of this stuff, but in the end I wrote my own learning materials and didn't use a book.
The course was a victim of its success. The school mandated the course for non-Java programmers too, resulting in a lot of push-back from the non-Java students.
If anyone is interested, I have the syllabus online still (I've since retired) at <https://wpollock.com/>. Look for COP2800 and COP2805C. I can also send the Java teaching materials as a PDF to anyone interested (book length, but sadly not publishable quality).
>Someone else posted here they had 10 pages of proofs per week, for one course.
Huh. As a professor, I would not be able to grade this kind of volume in any serious capacity. Especially since proofs need to be scrutinized carefully for completeness and soundness. I wonder how their instructor manages.
> There are hurdles still to overcome. In particular, we still have to figure out a way to make the top of our diamond coatings atomically flat.
Not sure I understand this. Is this a requirement for real-world use? What happens if the outside of the coating isn't atomically flat? What makes this hard to do?
These are gigantic and interesting questions packed into some pretty tiny boxes :) I will try to capture some of the issues involved.
Caveat: For older processes, built on a larger scale (>1 micron), these kinds of details may not matter, in which you are right to question this point. But if you want to implement on cutting edge manufacturing processes, these details absolutely do matter.
To put this in perspective, in cutting edge process nodes, I've seen senior engineers argue bitterly over ~1 nm in a certain critical dimension. That's (roughly) about 5 atoms across, depending on how much you trust the accuracy of the metrology.
So, if ANY layer isn't "flat" (or otherwise to spec within tolerance), the next layer in the semiconductor patterning stack will tend to translate that bumpiness upward, or cause a deformity in adjacent structure. This is (almost) always bad. These defects cause voids, bad electrical/thermal contacts and characteristics, misshapen/displaced structures, etc, etc
Crystallization in thin-film (especially conformal/gap-filling films) is a tough job which many poor PhD students have slaved over. Poly crystalline material is arguably harder to control in some key ways vs mono crystalline, since you don't have direct control the specific crystal grain orientation and growth direction. That is, some grain orientations will grow quickly, and others growing slowly. You can imagine the challenge then of getting the layer to terminate growth without ending up too jagged on the ~nm scale. After that you also get into the fun world of crystal defects, grain size, and deciding if you need to do some more post-processing (do I risk planarizing?)
Hopefully I have captured some of the pieces involved in an understandable way.
All semiconductor manufacturing techniques are based upon precisely flat layers of material that can be stacked and/or drilled into to produce a useful design. All vertical irregularities propogate to the layers above and can cause thinner layers when an upper layer is milled flat
This. A quick scan of the wikipedia page for diamond material properties suggests you are very correct. It appears very chemically inert, with some outstanding exceptions: "Resistant to acids, but dissolves irreversibly in hot steel"
Also, removed/liberated particles of Diamond from the workpiece which failed to fully chemically dissolve into the slurry would then contribute to the abrasive in the slurry. If the slurry abrasive was not also diamond, then that could lead to some serious scratch/gouging of the work surface.
Perhaps not insurmountable, but wow, that sounds like a stiff challenge, especially when accounting for cost.
I wonder if diamond would be machinable with a dry (plasma) etch instead? I am purely speculating here, this is far out of my wheelhouse. But SiO2 is already very chemically inert (though considerably softer vs diamond), but manufacturers regularly dry etch it.
Sounds like you have some APS model. I had those issues, and switched to Cyberpower. The alarm can be muted and the battery lasts for many years.
A UPS is a must for me. When I lived in the midwest, a lightening strike near me fried all my equipment, including the phones. I now live in Florida and summer outages and dips (brownouts) are frequent.
I've got Cyberpowers actually. The alarm can be muted, but it doesn't stay muted. Especially when the battery (or ups circuitry) is worn out so a power dip turns into infinite beeping. But also if the computer is turned off.
Many years ago I had the same thing happen - actually came in the phone line, fried my modem and everything connected to the motherboard. More recently I had lightning strike a security camera - took out everything connected to the same network switch, plus everything connected to the two network switches one hop away. Also lit up my office with a shower of sparks. Lightning is no joke.
Doesn't it take more than a few minutes for one's circulation to return to normal after a BP measurement?
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