rckoepke

11 ms·

31.
by rckoepke 5y ago
See also: https://linearbookscanner.org/
32.
by rckoepke 5y ago
Very few loops need any real tuning. For most of them, an incredibly wide range of value works perfectly well. Systems usually have a lot of slack in them. It's hard for most field engineers to get experience tuning loops when there ar
33.
by rckoepke 5y ago
They are not always the lowest bidder. Colonial Pipeline was known for selecting the higher bids sometimes in order to ensure quality of work. They'd generally evaluate risk vs. quality vs. price. Colonial also kept multiple overlappin
34.
by rckoepke 5y ago
Generally the controls are firewalled from the administrative/business systems, not air-gapped. Production data (like gallons per minute of flow through the pipeline) must be sent from the controls to the business analytics software. T
35.
by rckoepke 5y ago
It makes some things more difficult. CD/DVD's are generally used instead. Sometimes other computers could be connected but in that case there would be some organizational procedure for attempting to make sure that other computer w
36.
by rckoepke 5y ago
That functionality would be local, before the one-way isolator. A human at a terminal located near the valve could still press a button to make that happen. That system could even be running windows (most are!). But a hacker wouldn't b
37.
by rckoepke 5y ago
Generally it's been the opinion that the control systems need to be modifiable. For example if you add a single valve in a facility which has 4,000 valves already, it would be nice to just add add a controller for that valve to the cur
38.
by rckoepke 5y ago
Indeed the best evidence supporting this view is that Natanz was fully air-gapped and still got destroyed by the Stuxnet hack. That said I have heard of customers expressing desire to control valves and pumps using iPhones, and believe ther
39.
by rckoepke 5y ago
It was not intended to be air-gapped. These systems generally communicate to business layers through firewalls. Onion-layer security rather than air gaps. Communication through the firewall isn't supposed to allow control over the valv
40.
by rckoepke 5y ago
TCP would not be possible if your physical layer doesn't support two-way communication. I think UDP would. Firewalls are currently used, and probably generally configured well. Petrochemical companies have a many-layered onion security
41.
by rckoepke 5y ago
I have no idea. Shutting down preventatively would be smart, and they had good leadership in their IT space while I was there. Friendly people who could make the hard decisions quickly, weren't afraid to pick up the phones to call peop
42.
by rckoepke 5y ago
I would disagree with this. No petrochemical company I've worked with had OT/PLC/SCADA layers enabled for remote login. Other middle layers, like the historian, potentially. But not the control system itself. It's possib
43.
by rckoepke 5y ago
Most petrochemical companies have an onion structure. There are lots of layers of firewalls with what are supposed to be limited communication paths for specific applications. We need to move to using physical layers where data can only be
44.
by rckoepke 5y ago
USB ports are generally disabled in BIOS or purposefully physically damaged on most OT systems I've worked on for oil/gas/chemicals. Many places are fond of using epoxy to block the ports.
45.
by rckoepke 5y ago
It can be already hacked but while power to the valves and pumps are removed then the SCADA system hacks can't cause physical damage. I haven't seen any evidence that the "OT" side of their network was compromised in a w
46.
by rckoepke 5y ago
I built some of the SCADA and IT systems for Colonial Pipeline. Many industrial SCADA systems (nearly all) send data from their "OT" systems (PLC/DCS/SCADA) to their "IT" and business layers (Historians/Ti
47.
by rckoepke 5y ago
I had a similar feeling installing Gentoo on my graphite iMac in 2004. Except in my case I received so, so much help from the IRC channel, particularly Joseph Jezak (JoseJX) who helped me with some very deep problems I had involving patchin
48.
by rckoepke 5y ago
Interesting! For me ESP8266/32 felt trivial to reach successful prototypes. With no prior experience it took me less than a week to create PoE temp/humidity monitors for a datacenter with Grafana and Prometheus. In contrast I have
49.
by rckoepke 5y ago
I've had trouble finding an answer to one question: I don't understand why one would need multiple drives. Seems like you could earn the coin, sell it for USD, erase the drive, and earn another coin with the same disk. What preven
50.
by rckoepke 5y ago
I don't understand why one would need multiple drives then. Seems like you could earn the coin, sell it for USD, erase the drive, and earn another coin with the same disk. What prevents this?
51.
by rckoepke 5y ago
Alienware's published lead time should be taken with a large grain of salt. My 3090RTX / Ryzen 5600X build just shipped 12 days after I ordered it, a full 3 weeks faster than the estimate I was given at the time that I ordered it.
52.
by rckoepke 6y ago
I really miss the old weatherspark. It was extremely performant and also had by far the best/most useful UI visualizations of any weather app to date. http://radar.oreilly.com/2011/09/weatherspark-weather-data
53.
by rckoepke 6y ago
I thought these numbers must be off but the YubiKey HSM really is $650 [0]. What justified that price? Can someone walk me through the typical use case/application for these? 0: https://www.yubico.com/product/yubih
54.
by rckoepke 6y ago
Instant wake for me. However any time I come across a password field in a website the computer freezes for a painfully long 10 seconds or so while it presumably decrypts my password vault. Sometimes this will happen multiple times per page
55.
by rckoepke 6y ago
What does this have to do with https://gpu.land/ ? I've been very impressed with NN-512 in your past postings but I'm failing to see the direct salience w.r.t the top level post. Perhaps readers would benefit from
56.
by rckoepke 6y ago
Also of note: https://renew.rice.edu/ . Discussed here: https://news.ycombinator.com/item?id=24026416
57.
by rckoepke 6y ago
I've done this exercise and generally what you want is a combination of your suggestion (which is elaborated by 'polyphora[0]) and 'p1necone's suggestion [1] Polyphora mentioned CIELAB as just one example, and it's
58.
by rckoepke 6y ago
I'd love if it had an excellent webcam. I imagined the M1 would have a better webcam than the 2015 Retina MBP but instead the newest built-in webcams are significantly worse in quality. I'd imagine including a camera system from a
59.
by rckoepke 6y ago
Worth mentioning that there's a new version of that here: https://github.com/scc416/Visual2 I don't believe the source code for the first version was ever released.
60.
by rckoepke 6y ago
I believe the first attempts at doing something like this were back in July of 2020. https://github.com/below/HelloSilicon : Someone with an early Developer Transition Kit (pre-M1 release) worked to convert the code fr

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