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Centmo

131 karma · joined June 6, 2021

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Centmo··on The last person standing in the floppy disk business
Especially when you're on floppy #25 of OS/2 Warp.
Centmo··on An extrasolar world covered in water?
The robot from I Am Mother
Centmo··on A prompt engineering guide for DALLE-2
Is this significantly different from Dall-E2?
Centmo··on The Lightning Network: Turning Bitcoin into Money
How much are Lightning transaction fees?
Centmo··on The Lightning Network: Turning Bitcoin into Money
The holy grail is a cryptocurrency that can scale to billions of users while maintaining sufficient decentralization and security to be immune to state-level attack and corruption. BTC in combination with the higher level protocols such as Lightning (and others not yet conceived) is the only system that I believe can achieve this.
Centmo··on The Lightning Network: Turning Bitcoin into Money
The 1.5-3.5% credit card processing fee for starters. Also, you can't use a CC to send money peer-to-peer globally at near-zero cost.
Centmo··on Compare Webb's Images to Hubble
Also, when comparing the deep field images I don't think it can be stressed enough the difference in exposure time between HST and JWST images (Hubble had a 10x longer exposure time). Many many more distant galaxies would become visible in the JWST image with the much longer exposure time. I look forward to seeing some long-exposure deep field images from JWST!
Centmo··on Tether Required Recapitalization in May 2022
Was just going to say that about the purchasing power of USD.
Centmo··on A simple math equation can transform your productivity
He must be one of the few that can recognize numbers and language while dreaming.

https://www.inverse.com/science/can-you-read-in-your-dreams

Centmo··on Predict 3D position of flying bugs and pest to shoot down them with a laser
Perhaps if the laser light were put through adjustable optics to set the focal point at the target. That way, anything sufficiently closer or further than the target along the laser's path will see non-dangerous intensity. Still don't want the thing accidentally targeting eye balls though.
Centmo··on Web3/Crypto: Why Bother?
The safest and most effective method for storing wealth that the unbanked currently have is to bury gold jewelry somewhere. Gold holds its value better than fiat, but is not easily divisible and there is a large cost to converting it to/from fiat. Bitcoin keys can also be buried, but if necessary they can also be memorized and transported across borders without risk of seizure. Also, having multiple wallets is not complicated; you may be underestimating the cleverness of the unbanked.

The parameters of the Bitcoin code are changeable (and have changed multiple times since inception) via hard-fork based on the 'voting' of the nodes which verify all new blocks and number in the tens of thousands distributed across the globe. The parameters of the protocol are set such that anyone can run a verification node on only a couple hundred dollars worth of hardware, thereby encouraging decentralization.

https://river.com/learn/can-bitcoins-hard-cap-of-21-million-...

Centmo··on Web3/Crypto: Why Bother?
A person's Bitcoin holdings can be distributed across any number of wallets. How does the thief know (1) their mark owns Bitcoin, (2) how much Bitcoin they are stealing, and (3) whether they have coerced the owner to hand over the keys to all of their wallets?

Energy storage is inefficient and expensive, so a new renewable project based around this is less likely to be funded and built than one that can directly monetize the excess. Profit and greed is the incentive structure for much of human society.

Bitcoin has all of the properties we need in a store of value for the base layer of a digital monetary system of the future. The energy expenditure is required to provide the highest level of security and decentralization which is needed for a global reserve asset. Any other system is vulnerable to attack or centralization, which will inevitably succumb to human greed like every fiat system in history.

Centmo··on Web3/Crypto: Why Bother?
You could think of where you store your wealth as a vote for the system which best represents your values, and for the system you would like to see proliferated. Your inclusion adds value to the network, which strengthens its security and helps push it up the adoption s-curve. The more users there are, the more services appear, and the more accessible and useful it becomes.

I was never that interested in monetary policy or the history of money until I found out about Bitcoin and started doing my own research.

Centmo··on iPhone camera app replaces person’s head with a leaf in photo
Clearly, the ML algorithm had been given the goal of optimizing the happiness of the user. It had ascertained that the user was quite active on social media and had tied a significant amount of their self-worth to the number of likes received from posts and photos. It had correctly calculated that the user would extract more enjoyment from the photo by way of likes if their friend's face were replaced with an arrangement of foliage. The user clearly did not like that friend very much anyway due to the lack of engagement with their posts. Truly impressive technology.
Centmo··on Web3/Crypto: Why Bother?
How about as a means to provide financial security to the world's 1.7 billion unbanked, a means for those who live under oppressive rule to preserve wealth in the face of rampant currency debasement, in a form that cannot be confiscated or stolen. Money-printing drives inflation which is is a regressive tax that disproportionally hurts the poor, who don't own real estate or stocks. It accelerates the wealth gap, which further strains our society. Bitcoin is a means to expand financial inclusion, and help level the playing field just a bit. It's not just about greed.

Regarding energy use, Bitcoin mining inherently seeks out the lowest cost electricity which turns out to be either stranded energy (not usable for anything else) or renewable (solar, wind, hydro). This is yet another reason to push governments to stop subsidizing fossil fuels. Also, since Bitcoin mining can be done at any time and in any place, it is able to act as the buyer of last resort for renewable projects whose energy production does not line up with grid demand. Having this extra buyer can greatly reduce the payback period for a proposed solar/wind project that otherwise would not have been able to attract the investment to build it.

Centmo··on The gift of it's your problem now
If you liked it so much, why don't you give a donation :)
Centmo··on Technology Behind the Lilium Jet
Agreed, the distributed battery system does not seem practical for the Lilium design but you could get at least part way there by segmenting the central battery into parallel modules with separate safety disconnects. Not sure about the feasibility of the parachute system, it may be impractical due to the aircraft weight as you mention.
Centmo··on Technology Behind the Lilium Jet
It certainly increases the safety factor, but should never be relied upon as the sole redundant backup system. There are situations where it will not do you any good such as hovering at low altitude. If the aircraft does not have a reasonable glide slope, most people would feel a lot more comfortable with one.
Centmo··on Technology Behind the Lilium Jet
A way around this risk is to come up with a design for which a total power loss is extremely unlikely (i.e. it would take multiple simultaneous non-correlated failures in a short span of time). This could be achieved through a distributed battery system where each motor has its own battery physically and electrically separated from the others, and critical flight electronics have their own backup batteries. A ballistic parachute is always nice as a last-resort hail mary.
Centmo··on Technology Behind the Lilium Jet
From a safety perspective (ignoring cost, though which is also critical for viability), I mean minimizing the number of 'Jesus bolts' in the design - single components that if they fail, you are in a world of trouble. In the Lilium for example, what if the tilt mechanism for one of the main wings locks up while in cruise, and you only discover this while coming in for a vertical landing? This could be due any one of many possible reasons: SW bug, electrical failure, mechanical failure, debris jamming the mechanism, etc. You've got one wing producing forward thrust and the rest producing vertical thrust which is not likely to end well. You need to either prove that every part of this particular system is extremely reliable or you need a redundant backup system in place. Due to the design, neither of these options are easy here.

Obviously you need to assume there will be motor-out situations in any eVTOL design and the system needs to handle this with full payload over the flight envelope needed for a safe landing. Lilium has the advantage of many propulsion systems to take over the lost thrust, but many other eVTOLs are questionable here.

The same thinking has to be applied throughout the entire aircraft design (electrical and mechanical) and then you need to test, test, test. Each failure mode, using full payload over the full flight envelope, stability testing under differing weather conditions, the list goes on. To give you a rough idea, having a flying prototype is great but once you are comfortable enough with the design to put in a test pilot under controlled, monitored, and ideal conditions, you are maybe 20% of the way towards something you can responsibly put into service. If you want to see a simple design, check out the Opener Blackfly.

Centmo··on Technology Behind the Lilium Jet
I ended up moving on for personal and geographic reasons, nothing to do with the tech. The tech is all there for short-haul flights with batteries as the only limiting factor for range and speed.

There are various paths to economic viability for an eVTOL aircraft but I don't see how Lilium's current prototype fits into any of them. Unlike an ultralight design, it will require a certified pilot to chauffer passengers around until the day when full automation moves into the aviation space. Other than selling as an extravagant toy, this limits it to air taxi service. The design is complex so will be very expensive to buy and to maintain, so I don't see it as an improvement over existing helicopters beyond the 'green' energy source and claimed lower noise.

I am familiar with the Moller SkyCar. Lots of promises were made and broken, and lots of money burned on that project. Many modern eVTOL concepts suffer from the same basic design flaw: forward flight hanging from small propellers is inefficient. If you care about range, you need the lift of a large airfoil. Moller also had stability issues, but the responsiveness of electric propulsion and the advances in IMUs have solved this problem.

I think you can have a viable eVTOL product without a hot-swappable battery in the same way that electric cars have shown.

Centmo··on Technology Behind the Lilium Jet
I was a core engineer in a different manned eVTOL project, so have spent a lot of time thinking about this technology and watching the space. Lilium raised some eyebrows recently with their SPAC IPO valuation of over $3B, without having released footage of a single manned flight. The prototype is unique and aesthetically appealing, but my engineering mind recoils at the complexity of the design. The variable pitch blades, the adjustable exhaust nozzles, the tilt-wing vectored thrust system, etc. With complexity comes cost, maintenance, and exponentially increasing failure modes. Safety is paramount in aviation, so all flight-critical failure modes require redundant backup systems, which further increase cost and complexity. It's a slippery slope.

The eVTOL space is currently seeing a Cambrian explosion of different design concepts, but the first to see economic viability I think will be the simpler ones.

Centmo··on Omicron variant more resistant to vaccine but causes less severe Covid: study
Fix the incentives, fix the world.
Centmo··on Ideal Monitor Rotation for Programmers
Now, you're going to need to stock up on these (https://www.digikey.ca/en/products/detail/sparkfun-electroni...) and start re-wiring your office.
Centmo··on El Salvador's Bitcoin use grows but headaches persist
These transactions are not occurring on the bitcoin network - they are occurring on the lightning network which is a second layer on top of the base bitcoin layer. Transactions here are virtually free and use virtually no energy. This is how bitcoin scales for many small transactions.
Centmo··on Scientists test medieval gunpowder recipes with 15th-century cannon replica
When I was thirteen, I had the brilliant idea to make my own gunpowder and use it to build a bomb to set off in the field across from my house. I looked up the recipe in my Encyclopedia Brittanica (this was the early 80's) and began collecting the ingredients. I will never forget the ratios: 75% Potassium Nitrate, 15% Charcoal, 10% Sulpher. After pulverizing the ingredients and combining, I funneled the mixture into a spent CO2 cartridge from a pellet gun. I inserted a sparkler as a fuse, and lay it up against a large tree. I lit the sparkler and ran around to the other side to wait for the explosion. After a painfully long wait, I heard a loud hissing sound and saw some something fly and land right at my feet, a jet of flames shooting out the tiny hole. I took off running but it never exploded. I was old enough to realize I had won a dice roll and never played with gunpowder again.