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Self-hosted GitLab for proprietary customer projects that I don’t want in the cloud. I don’t trust GitHub’s privacy promises — if only because of the risk of my own misconfiguration. The GitLab server runs on Ubuntu Server on a NUC and is accessed via Tailscale by our very small team. No need to make it visible to the outside world.

Slow, simple, inexpensive, safe, and good enough.


For micrograd: is there more documentation available than just the source code in the Github repo?


He (Andrej Karpathy) has got a series on youtube which goes through how he made it!

https://www.youtube.com/watch?v=VMj-3S1tku0&list=PLAqhIrjkxb...


Oh cool, thank you so much!!


Around 1980, in the age of 14, I took part in an US-/German student exchange programme of my school. As a German at that time, I received a supposedly lifelong US-Visum in my passport.

Some years later, as a grown-up, I started to visit the US a couple of times, for business (visiting trade shows, conferences and customers), and as a tourist.

Around the 10th trip, the immigration officer unexpectedly crossed out my visum in the passport upon entry. I was stunned. He explained to me, very friendly, "that the policies had changed, the visum type was not existant anymore and thus cancelled, in the future I would just have to fill a paper in the airplane, welcome to the United States".

Next trip I received the questionnaire in the airplane, with one of the questions being "has there ever been an US visum cancelled for you?". That seemed a difficult question to answer. Would I say "no", that seemed like lying, because a visum had - as a matter of fact - been cancelled for me. Would I say "yes", I probably could just keep sitting in the plane seat for an immediate return. I decided to clear this up with the friendly immigration officer.

Who turned out not to be friendly, at all. Before I could even open my mouth, he noticed the unanswered question on the form, yelled at me like crazy, made me get back to the end of the line (I had spent already almost an hour in the line), told me to better not come back with unanswered questions on the form (I chose "no" on the second attempt) and then kept me interrogating for 20 minutes, all the time giving me the feeling that I would go right home. I was finally allowed to enter and spent another hour with customs.

Didn't feel the urge to ever come back to the US. That was long before ESTA. And long before I started to collect exotic stamps in my passport, some of them showing arabic typefaces. And long before Europe became an enemy of the US.

I have been to African countries (which the current POTUS would describe as shithole countries), whose administrations were less erratic and unpredictable than the US currently are.


"[...]And most, if not all, nuclear power disasters were due to human error.[...]"

And the remaining nuclear power disasters were due to unpredictable natural disasters.

So at what time exactly did we eliminate human error and unpredictable natural disasters, so that we don't have to worry about the dangers of nuclear power anymore? It seems, I somehow missed this two super important historic events...


You are right. As I have come to understand, there is a difference in astronomic longitudes and geographic longitudes as they are used for navigation.

The extra parameter is a good idea. As I am implementing in Rust, I will follow the strong type system and provide two different types that can cast themselves into the other.


Thanks for the hints. I ordered two promising books in German language:

"Astronomie" by Pearson and "Astronomie in Theorie und Praxis" (3 volumes) by Erik Wischnewski. Thats some 2000 pages of stuff to read, so let's see where this takes me.


The piece was definitely written by an AI.

And a bad one at that. It is a redundancy nightmare.

To save your time:

"In 1951, the United States military initiated a program aimed at developing a nuclear-powered aircraft capable of unlimited range (ANP program).

The program’s goal was to create a nuclear reactor small enough to fit into an aircraft yet powerful enough to provide the necessary thrust while ensuring the safety of the crew from radiation.

General Electric (GE) initiated the HTRE (Heat Transfer Reactor Experiment) series to create and refine the technology necessary for integrating a nuclear reactor with a jet engine.

The reactor in the HTRE-1 was essentially a modified version of existing nuclear technology adapted for aviation use.

The HTRE-2 tested different configurations and setups to optimize the efficiency of the nuclear jet engine concept.

The HTRE-3 featured a more compact and efficient reactor design that was closer to what would be needed for actual aircraft implementation. The HTRE-3 incorporated a modified General Electric J47 turbojet engine, which was a well-known engine in military aircraft at that time. The HTRE-3’s design was sophisticated, involving a direct cycle in which the air passed directly through the reactor core, getting heated in the process and then expelled to generate thrust. Moreover, the HTRE-3 featured improved radiation shielding techniques

While the HTRE series ultimately did not result in operational nuclear-powered aircraft due to various strategic, technical, and ethical considerations, it significantly advanced the understanding of nuclear propulsion."


We've come a long way in material construction in the last 50 years, I wonder if this could now be built.


Would be interesting in a drone, no need for the weight of shielding


You’d need a lead catcher’s mitt after it lands. Might make maintenance a bit tricky.


I think it’s basically a non-starter to fly an open cycle nuclear reactor around spewing radiation out in its exhaust to rain down on the people below it. Even if it is a relatively small amount, and is fairly dilute at ground level.


Summarize using AI?


For example, try this prompt on ChatGPT:

"Please write a lengthy essay about the Aircraft Nuclear Propulsion program, including details about the role of General Electric and the Heat Transfer Reactor Experiment. I need about 100 paragraphs. I know, this is a lot, but it is ok if there is a lot of reduncancy in the essay."


Prompting an AI service, like ChatGPT, to write an essay of a certain length about a given topic, then adding imaging and publishing the output on a website.


And this is, what ChatGPT replied to the prompt:

"Sure, here is a detailed and extensive essay on the Aircraft Nuclear Propulsion (ANP) program, including the role of General Electric and the Heat Transfer Reactor Experiment. While aiming for comprehensiveness, this essay might contain some redundancy to fulfill the length requirement.

The Aircraft Nuclear Propulsion (ANP) program was an ambitious initiative undertaken by the United States during the Cold War era. Its primary goal was to develop aircraft capable of prolonged flight durations without the need for refueling, thus providing significant strategic advantages in terms of endurance and range. The program was marked by extensive research and development efforts, significant investment, and a considerable degree of technical challenge. The program is particularly notable for the involvement of major corporations such as General Electric and the development of significant technological experiments like the Heat Transfer Reactor Experiment (HTRE).

The concept of nuclear-powered flight emerged during the early stages of the Cold War, a period characterized by intense rivalry between the United States and the Soviet Union. The strategic advantages of nuclear-powered aircraft were clear: they could remain airborne for extended periods, potentially for days or weeks, without the need to land for refueling. This capability would be invaluable for strategic bombers and reconnaissance aircraft, providing a persistent presence over critical areas and enhancing deterrence capabilities.

General Electric played a crucial role in the ANP program. As one of the leading corporations in the United States with significant expertise in both aviation and nuclear technology, General Electric was well-positioned to contribute to the development of nuclear-powered aircraft. The company's involvement included designing and testing nuclear reactors that could be integrated into aircraft systems. This was no small feat, as it required overcoming substantial technical hurdles related to reactor design, thermal management, radiation shielding, and integration with aircraft systems.

One of the most significant technical challenges in the ANP program was the development of a suitable nuclear reactor that could be used in an aircraft. Traditional nuclear reactors used in power plants were far too heavy and bulky for aviation purposes. Therefore, the ANP program focused on developing compact, lightweight reactors that could provide sufficient power for sustained flight without compromising the structural integrity or performance of the aircraft. This led to the development of several experimental reactor designs, including those tested under the Heat Transfer Reactor Experiment (HTRE).

The Heat Transfer Reactor Experiment was a series of tests designed to evaluate the performance and feasibility of nuclear reactors for aircraft propulsion. These tests were conducted at the Idaho National Laboratory and were critical to understanding how nuclear reactors could be effectively integrated into aircraft systems. The HTRE program involved several iterations of reactor designs, each incorporating lessons learned from previous tests. These reactors were designed to test various aspects of nuclear propulsion, including heat transfer efficiency, radiation shielding effectiveness, and overall reactor performance.

The first reactor in the HTRE series, HTRE-1, was primarily focused on demonstrating the basic principles of nuclear-powered flight. It was a significant milestone, as it successfully demonstrated that a nuclear reactor could be used to generate the necessary power for aircraft propulsion. HTRE-1 was followed by HTRE-2 and HTRE-3, each of which incorporated improvements and refinements based on the findings from earlier tests. These reactors were tested under various conditions to simulate the operational environment of an aircraft, including high-altitude and high-speed flight conditions.

One of the critical aspects of the HTRE program was the focus on heat transfer efficiency. In a nuclear-powered aircraft, managing the heat generated by the reactor is of paramount importance. Efficient heat transfer systems are essential to ensure that the reactor operates within safe temperature limits while providing sufficient power for propulsion. The HTRE reactors were designed with advanced heat exchanger systems that could effectively transfer heat from the reactor core to the aircraft's propulsion system, enabling sustained flight without overheating.

Radiation shielding was another major challenge addressed by the HTRE program. Nuclear reactors emit significant levels of radiation, which can be harmful to both the aircraft's crew and sensitive electronic systems. Effective shielding is necessary to protect against this radiation while minimizing the additional weight that the shielding adds to the aircraft. The HTRE reactors were designed with innovative shielding materials and configurations to minimize radiation exposure while maintaining the overall weight and performance of the aircraft.

General Electric's contributions to the ANP program were not limited to reactor design and testing. The company also played a key role in developing other critical components of the nuclear propulsion system, including control systems, fuel handling systems, and safety protocols. These components were essential to ensure the safe and reliable operation of the nuclear-powered aircraft. The integration of these components into a cohesive system required meticulous engineering and testing, with a focus on reliability and safety.

Despite the significant progress made under the ANP program, the initiative faced numerous challenges and criticisms. One of the primary concerns was the safety of nuclear-powered aircraft. The potential consequences of a nuclear reactor failure or crash were catastrophic, raising concerns about the feasibility and wisdom of deploying such aircraft. Additionally, the technical challenges of developing a practical nuclear propulsion system proved to be more formidable than initially anticipated. The weight and complexity of the required shielding, combined with the challenges of heat management and reactor control, posed significant hurdles.

The ANP program also faced competition from other technological advancements. During the same period, significant progress was being made in the development of intercontinental ballistic missiles (ICBMs) and other advanced conventional aircraft. These technologies offered alternative means of achieving strategic objectives without the inherent risks and challenges associated with nuclear-powered flight. As a result, the perceived strategic value of nuclear-powered aircraft diminished over time.

In light of these challenges and shifting strategic priorities, the ANP program was eventually canceled in the early 1960s. The decision to terminate the program was influenced by a combination of technical difficulties, safety concerns, and the emergence of more viable alternatives. Despite its cancellation, the ANP program left a lasting legacy in the field of aerospace engineering and nuclear technology. The research and development efforts undertaken during the program contributed to advancements in reactor design, heat transfer systems, and radiation shielding, which had broader applications beyond aviation.

General Electric's involvement in the ANP program also had a lasting impact on the company. The expertise and experience gained through the program contributed to GE's broader capabilities in nuclear technology and aerospace engineering. While the dream of nuclear-powered flight was never fully realized, the lessons learned from the ANP program informed future projects and initiatives in related fields.

In conclusion, the Aircraft Nuclear Propulsion (ANP) program was an ambitious and technically challenging initiative that sought to develop nuclear-powered aircraft capable of prolonged flight without refueling. General Electric played a crucial role in the program, contributing to the design and testing of nuclear reactors and other critical components. The Heat Transfer Reactor Experiment (HTRE) was a key element of the program, providing valuable insights into reactor performance, heat transfer efficiency, and radiation shielding. Despite its eventual cancellation, the ANP program left a lasting legacy in the fields of aerospace engineering and nuclear technology, highlighting both the potential and challenges of nuclear propulsion."


I wish they would have used the term "predicted" instead of "predicts" in the title of their article (just to keep my blood pressure down).


At least they use "very small" in the title, whereas here it's just "small" (maybe NASA edited it in the meantime?).

...but fortunately the asteroid was in the news a few days ago, so I correctly predicted (ha!) that they are referring to that one.


1967, Guy Debord: The Society of the Spectacle

https://en.wikipedia.org/wiki/The_Society_of_the_Spectacle

"Debord traces the development of a modern society in which authentic social life has been replaced with its representation"


Similar to Baudrillard, Great to read Debord and Baudrillard in the same sitting for extra flavour.


Calibre is outstanding - really one of my most important research tools. Fulltext search over the content of an entire library is a killer feature. I maintain a couple of hundreds books in PDF format and sync them automatically with a Samsung tablet.

Version 7.0 crashes on my Ubuntu 23.10, unfortunately. Had to return to 6.29.0.


If you run it from the terminal you can see the error. For me on 22.04 it was missing a dependency:

    sudo apt install libxcb-cursor0


Yess, thanks! Stupid me.

Installer is also hinting for the missing dependency now before installation.


Wait, full text including into PDFs? I didn't know that, that's really big!


Yep! In the search field above the library window, press the "FT" button on the very left. You have to create the index the first time you use the feature. It takes a while and from there on new books are indexed automatically.

FT search has word and phrase search, boolean operators and NEAR search abilities. And there is a really cool match list, giving some context of the match before you actually go to it in the PDF file.

You cannot search across libraries, though.


Note: AS far as I know, Calibre does not do OCR, so a PDF with only scanned content will not work.


I've had good luck using Tesseract [0] for scanned PDFs. If you're not CLI-inclined, there are several GUIs for it available [1]. I have had good luck downloading scanned PDFs from archive.org and running them through Tesseract.

Did not know about Calibre for this - I was relying on opening each search and searching it individually.

[0]: https://github.com/tesseract-ocr/tesseract [1]: https://www.opait.com/tessstudio/


OCRmyPDF is a tool using Tesseract, specifically designed for PDFs. I would recommend that over pure Tesseract.

https://github.com/ocrmypdf/OCRmyPDF


I recommend running any such PDFs through OCRmyPDF.

https://github.com/ocrmypdf/OCRmyPDF


Oh, lol, I never knew that.

I created a script that dumped my library of 1000s of books to .txt and then grepped them.


If you want even faster search across different formats, you can try ripgrep-all ( https://github.com/phiresky/ripgrep-all ). It can search across epub, docx, pdf, zip, mp4 etc. If you are handy with the tool, you can write custom adaptor to search across images using OCR with tesseract.


Curious on "as research tools" - do you use it to manage research papers?


I utilise zotero for this. Was unaware that calibre could do this; the search bit.


Could you tell me what software you are using for syncing?


I am using "Calibre Sync" on Android (Payware: US$ 5,49 and worth every penny).

For viewing/annotating on Android I use Flexcil.


Why not just use something like syncthing? Does it offer more advanced features than just syncing files?


> Does it offer more advanced features than just syncing files?

Yes! Covers, Metadata (searchable and including custom columns and comments), reading progress, filters (important for me: tags), different layouts, virtual views.

And it can use the full text search of Calibre (but only when connected to the Calibre content server).


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