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dosshell

1,310 karma · joined June 27, 2014

Sweden Eye tracking
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dosshell··on Glass discs that can store 360TB and remain intact for billions of years (2016)
Just speculating, but if you can index in 5 dimensions to get your data, should it not be called 5D?

data = read_bit(x, y, z, yaw, size)

But i agree, i would appreciate more information if they are going to use buzz-words.

dosshell··on Why Hong Kong Is Still Marching
I agree that one should respect other countries law, from their point of view. But when you are not allowed (read killed) to protest against the ones who decides the law, that is a big problem whatever the laws are.

Democracy is not only about majority votes, it is about free speech, the ability to review and criticize the government. It is about that the people do not get censored information but where the people are the bosses of the government, not the other way around.

dosshell··on AMD Ryzen 9 3950X is the fastest processor on Geekbench
And it looks like it has room for overclocking. Here to 5GHz and 65499 points in Geekbench 4 (record for Core i9-7960X is 60991 points)

https://m.youtube.com/watch?v=1woeitoCXsQ

dosshell··on Flying-V: Flying long distances energy-efficiently
Maybe there is region differances here. Here in Sweden most RC-Wings, actually all, I have seen have been self made and do not use any active controller.

What kind of observations do you have to support your statement?

Ps. Most of them I have seen, and built, has been to play a game where you put a string on your tail and try to cut each others with the propeller. They were airodynamic stable.

dosshell··on A Visual Introduction to Morse Theory
I think you are a little bit confused.

This is about Morse theory (topology), by Marston Morse. The Morse code you are talking about is something else, by Samuel Morse.

dosshell··on In Defense of Fahrenheit
> The truth is, outside of a chemistry lab I don't care that much about the freezing and boiling points of water

What? Freezing point of water is one of the most important things with temperature outside. Will it snow or rain? Will the lake freeze or melt? Will the road be slippery or not. That is like... the most important thing about temperature and outside.

However, I agree that the boiling temperature of water is not much used outside in a daily life.

dosshell··on Show HN: Lorem Picsum – Lorem Ipsum but for photos
Wonderful, this may be.. IS the best product website I have ever seen!

If you have not thought about it: images does not really work for place holders for charts. Maybe placeholders for pie-, bar- and line-charts etc, can be a feature to come?

dosshell··on Speedgate: World’s First Sport Generated by AI
They say you can use spherical balls too (to the right in the rule image). It seems to not be important for the game.
dosshell··on YouTube bans comments on all videos of children
I guess I'm reading the words to strictly

- We will stop giving you money

- We will force you to stop by delete the channel

I guess it can feel the same for many creators and be the same thing when communicating on twitter. (No sarcasm intended)

dosshell··on YouTube bans comments on all videos of children
Limited Monitization

Video that include minors and are at risk of predatory comments may receive limited or no ads (yellow icon). If you think we made a mistake please appeal [link]. We will continue to refine our approach in the coming weeks and months.

Is misstaken as deletion? English is not my first language, but I have a hard time reading this as "we may delete your channel".

dosshell··on YouTube bans comments on all videos of children
YT also ask for referns so they can correct the faulty information.

If i understand the twitter thread correctly, he referens that ads can decrease, and this somehow in his mind means that YT will delete his channel...

Edit: In my world, that is called a lie.

And well, who wants to advertize if the comments is full of pedophils?

dosshell··on Show HN: I taught my little brother JS, and he made this videogame in a week
My code when i was kid was half english and half swedish, heck even today when i write simple "run once"-code they often have some swedish named variable.

Funny story from ~2005, a company developed a jvm for a special cpu and was aquired by a bigger company. After the aquasition 2 developers had to search the code base for two weeks after swedish swear words, they replaced them with the word of dandelion in swedish ("maskros").

What I want to say is that it is very common to mix english and ones native language.

dosshell··on JSCPP, a simple C++ interpreter written in JavaScript
Strictly speaking, C++ is not anymore a superset of C. Mostly syntatic sugar but still, some C code can not be parsed by C++. But yeah, i know what you mean, i guess this is a bastard of C and C++?
dosshell··on Why OpenCV uses BGR color space (2015)
Interesting link! Yhea, I guess JPEG destroys a lot information low light images.

> probably because most cameras, except DSLRs, don't support storing raw images

This may be true for consumer cameras but not for machine vision cameras. Most color machine vision cameras do support the Bayer format. Basler, FLIR (Point Grey), IDS and so on all support the Bayer format. If you roll your own camera you definitely have to deal with the Bayer format from the sensor you are using.

And if you do not want any compression on your data-set images the Bayer format also takes less space than the RGB format.

I'm not arguing it is a good idea, I'm just interested if it works :)

dosshell··on Why OpenCV uses BGR color space (2015)
Interessting. Why is not the "raw" sensor format, for example Bayer BG8, used more in deeplearning? Would it not contain a little bit more correct information? and if used, we could skip the Bayer-> RGB conversion completly.
dosshell··on Why the Swedish Vasa Ship Sank – An Engineer's Explanation
This reminds me of a quote from Scott Myers:

The Vasa was a 17th-century Swedish warship which suffered such feature creep during construction that it sank shortly after leaving the harbour on its maiden voyage. In the early 1990s, the C++ standardisation committee adopted the Vasa as a cautionary tale, discouraging prospective language extensions with "Remember the Vasa!" Yet C++ continued to grow, and by the time C++ was standardised, its complexity made the Vasa look like a rowboat.[0]

[0] https://youtube.com/watch?v=ltCgzYcpFUI

dosshell··on Conflating pointers with arrays: C's biggest mistake? (2009)
This was written in 2009, didn't rust first appeared in 2010?
dosshell··on Sponsorship needed for new OS/2 web browser (2017)
I do not know if this counts but:

- change default port for sshd will take away 99.9% off all random attacks.

- many copy protections may count as this. Some of them uncrypt themself before running so that it is harder to disassemble the bin file on disc. Also some more creative protections have been around, https://www.makeuseof.com/tag/5-strange-video-game-copy-prot...

dosshell··on Go 1.11 Beta 1 is released
It is not deterministic on playground if it is not cached.

You can add dummy code to the file to break free from the cache.

dosshell··on DevTube: Searchable index of developer videos
Since he embedd youtube videos like a "youtube service" i'm not sure the logo is the biggest issue here? Or are you allowed to do that? Make a new youtube front?
dosshell··on Blender is testing PeerTube after YouTube blocks their videos worldwide
Wait, is it really solved now? I get the following error for many videos:

> This video contains content from BlenderFoundation. It is not available in your country.

For example: https://www.youtube.com/watch?v=kes2qmijy7w and all other videos in "Blender Fundamentals" playlist.

I'm located in Sweden.

dosshell··on Dissolving the Fermi Paradox
And some numbers from the paper:

> we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively).

> ’Where are they?’ — probably extremely far away, and quite possibly beyond the cosmological horizon and forever unreachable.

dosshell··on GitLab Isn’t Really Open-Source
> Rebase merge requests before merge

> Approve Merge Requests

What!? This is not true. You can both rebase and approve merge requests with with Gitlab ce. You can even force semi-linear history. The webpage must be outdated - or did i misunderstood something?

Source: I do it every day.

dosshell··on Patents: how and why to get them
The article forget to mention that patents is per country. This means that you have to choose which countries you want to protect yourself in. You also have to translate the application to the language to those countries and file it there. Just because you get a patent in US does not mean that you will be granted one in Germany for example. My experience is that it is harder to get a patent in EU (better prior art check etc).

The countries you choose not to patent in are free to use your claims and specifications as much as they want. (but they can not sell, marketing etc in the protected ones)

What can be patented can also slightly differ, specially in SW.

dosshell··on AT&T updates firmware to block access to 1.1.1.1
In swedish: https://www.svd.se/telia-fortsatter-att-ge-facebook-fordelar

(note that its not an article but a debate post)

dosshell··on Is sorted using SIMD instructions
Do you have any explanation of why you think so? And how much is hugh data for you?

I work with image processing, >1GiB/s. We optimize for each platform for hand, many embedded platforms but also x86_64. Most of our work is detectors and loss-less compression and we could not do these things in realtime if it weren't for SIMD/MIMD.

dosshell··on Google is shutting down its goo.gl URL shortening service
I do not understand. Please say what you mean in your message instead of just dropping some urls:s. For example now, your url:s goes to this submission and an unknown (!?). If you had written what you meant at least I could understand your point.
dosshell··on PID Without a PhD (2016) [pdf]
How do you mean with "better result"?

For a non-linear system, machine learning can perform much better and solve more complex tasks. Like walking for a humanoid robot. A linearzied PID solution can not beat that.

For linear systems:

Depends of what you mean with better I guess. My understanding is that you can place some of the poles of a system with a PID pretty much where you want. So for a simple linear system: no.

There exist also other controllers where a LQR can be used in linear systems to get a perfect theoritical controller based upon to minimize the cost of control outputs. (yes, several outputs).

However maybe a ML can be used to choose and tune the controllers better than humans?

EDIT: Also, the discretication is not always perfect (backward or forward euler is common estimates). So maybe ML can help in that too?

dosshell··on PID Without a PhD (2016) [pdf]
I am a little suprised that the author does not use a low-pass filter for the D part, for example 1/(1+s Tf) and instead tells you to modify the hardware.

Sure, you need cut off the noise with hardware in respect to your Nyquist frequence but you can still have a lot of high frequency noise. And it is not always possible to use hardware filters to get rid of the noise, for example if your are tracking an object with a camera and the x,y is your input to the pid. Ofcourse you can skip the D part.

What am I missing here?

I also find it more easy to use a reset based integrator anti-windup, where you specify your limits on your control signal instead of limiting the integrator.

Here is an diagram of what I usally do:

          +--------+           +------+
   -y     |    1   |           |      |
 -------->+ ------ +---------->+ Kd*s +----+
          | 1+s*Tf |           |      |    |
          |        |           +------+    v
          +--------+   +----+            +-+-+       +-------+   
   e=r-y               |    |            |   |       |    __ |      u
 --------+------------>+ Kp +----------->+ ∑ +---+-->+ __/   +---+--->
         |             |    |            |   |   |   |       |   |
         |             +----+            +-+-+   |   +-------+   |
         |                                 ^     |               |
         |   +----+   +---+    +-----+     |     |     +---+     |
         |   |    |   |   |    |  1  |     |     |   - |   | +   |
         +-->+ Ki +-->+ ∑ +--->+  -  +-----+     +---->+ ∑ +<----+
             |    |   |   |    |  s  |                 |   |
             +----+   +-+-+    +-----+                 +-+-+
                        ^                                |
                        |                                |
                        |      +----+                    |
                        |      |    |                    |
                        +------+ kt +<-------------------+
                               |    |
                               +----+


The kt gain will reduce the integrator when we have saturated output.

Does some one knows the pros and coins with the different anti-windup solutions?

dosshell··on Will Cash Disappear?
Also, many stores in Sweden does not accept cash.

All stores I have visited the last year accepted card or Swish but around 15 % of them did not accept cash. The argument is that cash is expensive to handle and it increases the risk of robbery.

I have only heard about some old people (bank trust issue) and people with economic problems (no credit card) that feel like this is a problem.

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