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Quorten Blog 1

First blog for all Quorten's blog-like writings

Giant ancient South American water distribution system

quorten

2020-06-10

Categories: random  
Tags: random  

Wow, this is really interesting. Nasca lines? Puquitos? The purpose behind these giant colossal constructions has now been revealed. It was behind a massive water distribution system built to bring water to one of the most arid places on earth, to grow farms, to build a highly advanced civilization. Wow, now that is really interesting, they were really expert builders out in the South American, Mesoamerican region.

Those who have the technological know-how to distribute water in such a reason, they hold the very key to life itself. And, therefore, they wielded a significant amount of political power.

20200609/https://getpocket.com/explore/item/the-ancient-peruvian-mystery-solved-from-space

Some insightful articles about the back-story before the Minneapolis riots

quorten

2020-06-10

Categories: random  
Tags: random  

Here are some insightful articles about the issue behind the Minneapolis riots being long in the making. The signs were there decades in advance, it was just a matter of time until something broke out large. Also, some good general background on the issue of housing discrimination. They very interesting point that made: your home basically determines everything else in the rest of your life. Like, wow, really, that’s a really powerful statement about just people’s homes. But, the key. “Location, location, location” is what real estate agents say, not “home, home, home.”

20200608/https://www.theatlantic.com/ideas/archive/2020/06/minneapolis-long-overdue-crisis/612826/
20200608/https://www.npr.org/transcripts/601131468

Wow, 16th century math textbook with pop-up models

quorten

2020-06-09

Categories: media-prog   unlipic  
Tags: media-prog   unlipic  

Wow, 16th century math textbook with pop-up models. The book was a translation of Euclid’s classic geometry publication. That really was a thing, the pop-up models were hand-glued into the textbook after printing. Pretty interesting, especially that back then, they were willing to not only put together such an expensive textbook, but that people were also willing to buy it in substantial numbers.

20200609/https://www.amusingplanet.com/2020/06/a-16th-century-math-book-with-pop-up.html

OpenCL on Raspberry Pi is hard

quorten

2020-06-08

Categories: raspberry-pi  
Tags: raspberry-pi  

OpenCL on Raspberry Pi, it should be easy because of the VidCore IV GPU, right? Wrong. Apparently, for years, there was no official software support, and only recently are we seeing some in-development libraries crop up. Use VC4CL to get real code running on the GPU, there is another OpenCL library `` that simply so that you can write “native kernels” in OpenCL that are pretty much worthless since they run on the CPU.

20200608/DuckDuckGo install opencl raspbian
20200608/https://github.com/doe300/VC4CL
20200608/https://github.com/pocl/pocl

Unfortunately, Raspberry Pi 4 is not supported by this software because of the newer VidCore GPU it uses. So, that’s a real bummer if you’re hoping to do OpenCL on a Raspberry Pi 4.

Also, this is another little bit of a bummer, VidCore IV is a SIMD GPU, not a SIMT GPU like those of Nvidia fame. But, you get what you get. Better than nothing, that’s for sure.

OpenCL 1.2, embedded profile is the limit of support for OpenCL on Raspberry Pi. Sure, it leaves features to be wished, but again, anything is better than nothing.

More information for calculating COVID-19 uncertainties

quorten

2020-06-05

Categories: covid19  
Tags: covid19  

I’ve found some more good information on calculating with uncertainty on Coronavirus.

20200605/https://www.theatlantic.com/health/archive/2020/06/covid-19-coronavirus-longterm-symptoms-months/612679/

30% false negatives, especially when diagnosed more than a week later.

Wow, this is interesting, about people being disbelieved about being chronically sick. There’s a formal name for that, ME/CFS. A few other quotes are also highly insightful.

Formally, Ramey has myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and complex regional pain syndrome. Informally, she’s part of a group she has dubbed WOMIs—women with mysterious illnesses. Such conditions include ME/CFS, fibromyalgia, and postural orthostatic tachycardia syndrome. They disproportionately affect women; have unclear causes, complex but debilitating symptoms, and no treatments; and are hard to diagnose and easy to dismiss. According to the Institute of Medicine, 836,000 to 2.5 million people in the U.S. alone have ME/CFS. Between 84 and 91 percent are undiagnosed.

…

Whatever the case, as the pandemic progresses, the number of people with medium-to-long-term disabilities will increase.

…

Read on →

Computing roots, logarithms, and exponents, part 2

quorten

2020-06-04

Categories: media-prog   unlipic  
Tags: media-prog   unlipic  

Previously, I mentioned some methods to build a table of logarithms based off of adding or subtracting fractional exponents to attain an arbitrary fixed-point decimal power of a base. In general, this is a fast but possibly inaccurate method for computing arbitrary logarithms and exponents.

Here, I present methods that may have better numerical stability on accuracy, are easy to understand how they are fully general, but may come with the extreme expense of being computationally expensive.

So, first of all, computing nth roots using Newton’s method. It’s rather easy once you setup the right equations.

To determine x = sqrt(n):
n = x^2
0 = x^2 - n
y = x^2 - n
f(x) = x^2 - n

To determine x = n^(1/r):
f(x) = x^r - n

Read on →

Shingled Magnetic Recording is slow

quorten

2020-05-31

Categories: pentax-k-1-camera  
Tags: pentax-k-1-camera  

Shingled Magnetic Recording (SMR). This was a hard drive technology I was really excited for because of the increased storage density, and for photo use, high density at low cost is one of the most important things you can ask for. But, the crux of SMR hard disk drives, I realized as I started using my SMR hard drive for virtualization, is that SMR writes are slow. And yes, this actually makes them unsuitable for particular uses like RAID.

Therefore, there is a class-action lawsuit against Western Digital in the making due to not properly advertising and marketing its drives that were using SMR.

20200531/https://www.tomshardware.com/uk/news/wd-class-action-lawsuit-smr-hard-drive-us-canada

Interesting CPU packaging boxes, and custom retail packaging design/manufacturing companies

quorten

2020-05-31

Categories: 3d-printing  
Tags: 3d-printing  

Intel kills off Core i9 9900k speciality dodecahedron packaging? Wow, now this is interesting. Those marketing pictures showing the dodecahedron picture you’ve been seeing? Those were actually representative of the actual retail box that the CPU was sold packaged in, it wasn’t just a cute marketing logo. Wow, now that is really interesting. Alas, the fancy packaging has come to an end, after Intel sent out a product change notification (PCN).

20200531/https://www.tomshardware.com/uk/news/intel-kills-off-core-i9-9900k-speciality-dodecahedron-packaging

Really, I’m with what some of those other folks were thinking, those photos of bulk packaging arrangements really looks like a box of chocolates.

This was purportedly first inspired by, and meant to compete with, AMD Threadripper packaging. Well, it’s not odd shaped like Intel i9 9900k. Just that it’s huge and has rounded corners. No heat sink is actually included in all that extra space, though, just like the Intel dodecahedron box.

20200531/https://hothardware.com/news/amd-unveils-ryzen-threadrippers-massive-and-flashy-retail-packaging

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Interesting updates on Raspberry Pi and Raspberry Pi 4

quorten

2020-05-31

Categories: raspberry-pi  
Tags: raspberry-pi  

Well, well, after updating my Raspberry Pi 4 software, I’m still seeing the video vertical synchronization tearing problem present. I thought they purportedly fixed that? Well, I’m not seeing the improvements. Well, that’s too bad, I better go searching around. I didn’t find what I was looking for, but I found some other great news.

Finally, the Wikipedia article on number of Raspberry Pis sold has been updated! We’re now at 30 million and counting!

20200531/https://en.wikipedia.org/wiki/Raspberry_Pi 20200531/https://twitter.com/EbenUpton/status/1205646606504275968?s=19

The other thing, Raspbian has been renamed to Raspberry Pi OS, long story short. Wondering why updates to Raspbian were always so sluggish when Raspberry Pi 4 hit the market? Raspbian was never officially chartered by the Raspberry Pi Foundation or Raspberry Pi Trading. Rather, it was a small but passionate community-led project that shared a common interest in education and gained a foothold. The most significant customizations were to tune the kernel for the ARMv6 that is used in BCM2835 Raspberry Pi models. Unlike Debian armel, BCM2835 ARM has hardware floating point, but not NEON, fashpaths, and some specialized ARMv7 scalar instructions. So those kernel tunings were necessary for optimal performance on Raspberry Pi, else stock Debian would compile without any hardware floating point.

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Insightful dream reflection on people's attitude toward safety

quorten

2020-05-31

Categories: motor-vehicle  
Tags: motor-vehicle  

“Why won’t people just follow the rules?”

That was the name of an article about industrial safety and industrial accidents that I’ve read a few weeks ago. Then I had a dream quite closely related to the subject matter of the article. I’ve been thinking about it for quite a while, and decided that, yeah, this really is legitimate reasoning coming out of this dream. Sometimes, dreams that people have are more fantasy than logic, but this one was rather sound logic, great for reflection in a technical context.

The key points:

  • Humans have a generally poor understanding of safety with modern industrial technology.

  • The primary form of industrial technology that is most desirable to use in direct contact with laypeople is, of course, motorized transportation. This is, of course, because it is necessary that the user/beneficiary of the machine be within its proximity, else motor vehicles could not be used to transport humans, only objects and animals.

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