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jamessb

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jamessb··on Photographic Reference Scale (2019)
> You're going to have a hard time calibrating that without a whole bunch of patches with known reflectance/transmission profiles

If you care about accurate color, you do use a card with "whole bunch of patches" of different colors. For example, these British Library guidelines on photographing and scanning archival material say:

"An industry-approved colour chart or greyscale reference card is essential in order to check the accuracy of the colour captured in the photographs. This is a physical card that is available to purchase on the internet. It cannot be downloaded from the internet and printed, or inserted into your image using software. Approved colour checkers that have been used in EAP projects include: Gretag Macbeth ColorChecker, QP cards, Kodak Color Control Q13 card, Past Horizons Bookmark Photo Scale."

(https://eap.bl.uk/sites/default/files/Guidelines%20for%20pho...)

ColorChecker (“Macbeth”) Chart: https://poynton.ca/notes/color/GretagMacbeth-ColorChecker.ht...

QP cards: https://www.argraph.com/QP202.html

Kodak Q13: https://www.kodak.com/en/motion/page/color-separation-guides...

Bookmark photo scale: https://www.pasthorizonstools.com/Photo_scale_bookmark_p/boo...

jamessb··on Show HN: I built an app to create repeatable checklists to help with ADHD
Checkli: https://www.checkli.com/

Process Street: https://www.process.st/

https://checklist.com/ also lets you create "checklist templates"

jamessb··on Apollo 11 implementation of Trigonometric functions (1969)
Fermat's Library is an annotation platform, so there are annotations on the linked version - click on the circles (or rectangles, depending on whether the side panel is open) on either side of the document to see the annotations.
jamessb··on Show HN: Convert data exports from various services to a single SQLite database
Simon Williamson's Dogsheep project [1] also provides importers to ingest data from various sources into SQLite databases.

[1]: https://dogsheep.github.io/

jamessb··on Show HN: An interactive visual history of Git development
After a user clicks on the streamgraph, the bottom-left displays information about commits by the corresponding contributor in the corresponding quarter; the contributor name is already a link to their GitHub profiles, but the "changes" count could also be made a link to the actual commits.

These links would have the format:

https://github.com/git/git/commits?author=gitster&since=2005...

or

https://github.com/git/git/commits?author=gitster@pobox.com&...

jamessb··on The Limits of Optimization
> We can now measure and analyze dimensions of personal and social life that we wouldn’t even have thought to measure a decade or two ago. It was always theoretically possible for us to count our steps, but altogether impractical. Now we can have it done for us passively.

Pedometers are much older than "a decade or two": https://en.wikipedia.org/wiki/Pedometer#History

https://walkertracker.com/the-evolution-of-the-pedometer/

jamessb··on Computer Security and the Internet: Tools and Jewels
> and includes two new chapters

Specifically, Chapters 12 and 13, on "Wireless LAN Security: 802.11 and Wi-Fi" and "Bitcoin, Blockchains and Ethereum".

jamessb··on OrganicMaps is Android and iOS offline maps for travel without trackers or ads
Organic Maps is a fork of MAPS.ME, after MAPS.ME jumped the shark and pivoted to something involving cryptocurency.

I think that "curated" refers to maintenance/development of the open-source project.

By "curated ... by MAPS.ME fouders" they mean that the Organic Maps maintainers include founders of the original MAPS.ME project (e.e.g, biodrankik is Alexander Borsuk, a former co-foudner, CEO, CTO of MAPS.ME [1,2]), which suggests that they have the experience to continue updating the app.

[1]: https://github.com/biodranik [2]: https://alex.bio/

jamessb··on The Cerebras CS-2 wafer-scale engine (850k cores, 40 GB SRAM)
This slide (https://images.anandtech.com/doci/16626/Cerebras%20WSE2%20La...) lists announced Deployments at:

Argonne National Laboratory

Lawrence Livermore National Laboratory

Pittsburgh Supercomputer Center

Edinburgh Parallel Computing Centre

GlaxoSmthKline

"Other wins in heavy manufacturing, Pharma, Biotech, military and intelligence"

jamessb··on Mechanisms in Modern Engineering Design (1979)
Probably not: https://www.fourmilab.ch/autofile/www/subsection2_38_3_4.htm...
jamessb··on A visual cash flow tool for Small Business Owners or Professors?
> We did our research and contacted Associate professors and Principal investigators on LI

Academics typically don't use LinkedIn much (I assume this is what you mean by LI); if you want to reach them through social media then Twitter is probably a better bet.

However, rather than contacting individual researchers, you might find it more effective to try contacting people in Research Services/Research Support teams, whose role includes helping academics with things like costing grant proposals.

jamessb··on Ask HN: What kinds of cookies are “required” for a website to function?
The answers to "What is the ‘strictly necessary’ exemption?" and "What activities are likely to meet the ‘strictly necessary’ exemption?" in this guidance FAQ gives some clarification from the UK Information Commissioner's Office:

https://ico.org.uk/for-organisations/guide-to-pecr/guidance-...

jamessb··on Police warn students to avoid Sci-Hub
As a native speaker of British English I did not find the title confusing: I think the confusion is that the typical meaning of "warn to" and "warn about" are different.

"warning someone to avoid something" suggests that there is a risk associated with the thing itself - they should avoid the thing

"warning someone about avoiding something" suggests that there is a risk associated with avoiding the thing - they should not avoid the thing

(e.g., "HMRC warns people about avoiding paying income tax")

jamessb··on Computational Algebraic Topology, lecture notes [pdf]
The webpage for the course [1] includes not just these lecture notes, but also 4 problem sets and links to videos of the lectures on YouTube.

[1]: http://people.maths.ox.ac.uk/nanda/cat/

jamessb··on I self-published a paperback and eBook using LaTeX and Pandoc
Yes - pandoc supports latex math if the `tex_math_dollars` extension is enabled: https://pandoc.org/MANUAL.html#math
jamessb··on The Dunant subsea cable
~~D'oh - yes, that formula is true only if the triangle is right-angled, which is true for only a single base length.~~

Edit: Actually, this is always true: we are considering a right-angled triangle where the base is the horizontal distance from the ground station to point under the satellite, the vertical part is the 550 miles between the point under the satellite and the satellite, and the hypotenuse is the line joining the satellite and ground station.

> if a sat is 500 miles up directly overhead that's the closest it ever will be, as it flies off the hypotenuse gets longer

Yes: as the horizontal distance d increases, then the length of the hypotenuse (sqrt(d^2 + 550^2)) increases.

However, the difference between this and the horizontal distance (sqrt(d^2 + 550^2) - d) decreases.

-----------------------------------------------

If the angle from the horizontal to the line between the satellite and base-station is theta, then:

sin(theta) = 550/hypotenuse => hypotenuse = 550/sin(theta)

tan(theta) = 550/base-length => base-length = 550/tan(theta)

difference in length = 550/sin(theta) - 550/tan(theta)

[which simplifies to 550 tan(theta/2)]

We are interested in angles between 0 degrees (horizontal - corresponding to the limiting case of infinite horizontal distance between the satellite and base station) and 90 degrees or pi/2 radians (straight up): https://www.wolframalpha.com/input/?i=plot+550%2Fsin%28x%29+...

This is always between 0 and 550. The triangle inequality holds: for a single hop from base-station to satellite, the increase in length is never more than 550.

But as you point out, there may also be multiple hops.

> So ideally you bounce off a sat overhead, (distance of 1100),

This is the shortest total ground-satellite-ground distance, but as you cover 0 horizontal distance it is the worst case: the difference between the ground-satellite-ground distance and the length of the direct ground-ground line is maximised.

jamessb··on The Dunant subsea cable
Yes, this is an oversimplification: the original statement seemed to be based on getting a fact about trigonometry backwards, and I was just trying to resolve the underlying confusion.
jamessb··on The Dunant subsea cable
But the correct statement is "no more than" not "at least".

Consider a right-angled triangle with base length d and height 550, corresponding to transmission from a base-station to a satellite. The hypotenuse has length sqrt(d^2 + 550^2), so the difference in length between the hypotenuse and base is sqrt(d^2 + 550^2) - d.

This has a maximum of 550 when d=0 (i.e., shooting straight up), and decreases as d increases: https://www.wolframalpha.com/input/?i=plot+sqrt%28d%5E2+%2B+...

Alternatively, consider the triangle inequality: the sum of the lengths of any two sides must be greater than or equal to the length of the remaining side. This directly implies that the difference in length between the hypotenuse and base is less than or equal the height [base + height >= hypotenuse implies height >= hypotenuse - base].

jamessb··on Ask HN: Why do got this vaccine mess – Problem explained from some expert?
This interview with the AstraZenaca CEO discusses scale-up and supply: https://www.repubblica.it/cronaca/2021/01/26/news/interview_...

It suggests the problem is with technology transfer to partners:

> "We had to change all of these. Then we had to do what we call technology transfer. So we go to each partner and we train them on the process. We train them on how to manufacture. And then, you know, some people are new to this process. It's like they learn the process. They don't know how to make the vaccine and they're not as efficient as others".

> "So you may have lower productivity. That's why we have a productivity going from one to three. And so, unfortunately, it's really bad luck. Actually, there's nothing mysterious about it. But look, the sites that have the lowest productivity in the network are the sites that are supplying Europe. And quite honestly, I mean, we're not doing it on purpose. I'm European, I have Europe at heart. Our chairman is Swedish, is European. Our CFO is European. Many people in the management are European. So we want to treat Europe as best we can. You know, we do this at no profit, remember? We didn't go into this to try and make money or whatever. We would like to treat Europe as good as possible. I actually do believe we treated Europe fairly".

jamessb··on Ask HN: Looking for a boilerplate contract for software development side job
I haven't used it, but SuperFriendly share their Service Agreement template: http://agreement.superfriend.ly/
jamessb··on How we made Typerighter, the Guardian’s style guide checker
I think the "20th century" solution to letting many users in different locations run regexes would probably have been to write a cgi-bin script in Perl, and have users paste text into a box on an HTML form.

The results page generated by the script could have checkboxes to mark each suggestion as useful/not-useful/incorrect and a submit button, with this feedback saved in MySQL.

(I'm not sure whether this qualifies as "without ... services")

jamessb··on Data Visualization and the Modern Imagination
For timelines, the book "Cartographies of Time" [0] has lots of historical examples.

There is also a recent presentation of the design space of timelines in "Timelines Revisited: A Design Space and Considerations for Expressive Storytelling" [1, 2]. This then developed into the Timeline Storyteller tool [3].

[0]: https://papress.com/products/cartographies-of-time

[1]: https://timelinesrevisited.github.io/preprint.pdf

[2]: https://timelinesrevisited.github.io/

[3]: https://timelinestoryteller.com/

jamessb··on Still alive
Robin Hanson had a 2013 blog post titled "Hail Scott Siskind" - the surname was redacted from both the post title and the URL slug sometime between 8 Jan [1] and 24 June 2020 [2] (Slate Star Codex was deleted on 22 June 2020 [3]).

So if a patient had googled "Scott Siskind" before the NYTimes contacted him, they may well have found the post linking the name to the blog.

[1]: https://web.archive.org/web/20200701000000*/https://www.over...

[2]: https://web.archive.org/web/20200701000000*/https://www.over...

[3]: https://slatestarcodex.com/2020/06/22/nyt-is-threatening-my-...

jamessb··on Show HN: Using flamegraphs to read big HN threads
Andrew McNutt's Forum Explorer also visualizes forum discussions and supports HN [1] (it was discussed on HN last year [2]).

[1]: https://www.mcnutt.in/forum-explorer/

[2]: https://news.ycombinator.com/item?id=19912550

jamessb··on Algorithms for Decision Making
Ben Recht [0] has worked on control theory and reinforcement learning.

See his blog post "What we've Learned to control" [1] and the survey paper "A Tour of Reinforcement Learning: The View from Continuous Control" [2] may be of interest.

[0]: https://people.eecs.berkeley.edu/~brecht/

[1]: https://www.argmin.net/2020/06/29/tour-revisited/

[2]: https://arxiv.org/abs/1806.09460

jamessb··on Descript – A collaborative audio/video editor that works like a doc
Maneesh Agrawala [1] and his group has done lots of similar work with the same basic idea of editing audio or narrated video as if it's text:

* Content-Based Tools for Editing Audio Stories [2] (the software is released as an open-source project called speecheditor [3])

* Text-Based Editing of Talking-head video [4]

* QuickCut: An Interactive Tool for Editing Narrated Video [5]

[1]: https://graphics.stanford.edu/~maneesh/

[2]: http://vis.berkeley.edu/papers/audiostories/

[3]: https://ucbvislab.github.io/speecheditor/

[4]: https://www.ohadf.com/projects/text-based-editing/

[5]: https://graphics.stanford.edu/projects/quickcut/

jamessb··on Seasonal Spirals
You might find Cycle Plots [1, 2] useful.

[1]: https://www.cvast.tuwien.ac.at/topics/cycle-plot-climate-dat...

[2]: https://www.perceptualedge.com/articles/guests/intro_to_cycl...

jamessb··on IMAP API – self hosted daemon to access IMAP and SMTP accounts via HTTP API
I think DavMail might meet your needs: http://davmail.sourceforge.net/
jamessb··on How to buy gifts that people actually want
> my pipe dream of a personal CRM or PSA

That sounds like Monica HQ: https://www.monicahq.com/

jamessb··on BiVector.net – Geometric Algebra for CGI, Vision and Engineering
It look like Chris Doran's company was acquired by Arm, and that he is back in academia as a fellow at Sidney Sussex College: https://www.sid.cam.ac.uk/people/dr-chris-doran
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