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Is iron a potential replacement for coal in steel and cement production?


it could be, but like other posters have mentioned, it takes a lot of energy to mine and refine the iron so it'd be in a usable state.

I think it's easiest to think of iron as another energy storage medium that could ease the peaks of renewable energy, by taking excess renewable energy to generate the iron, and oxidizing the iron for energy generation during peak demand periods with low renewable generation

It's like hydrogen in that way.


Making steel from ore using iron seems a bit weird. If you already have a method to reduce the oxide, why not use it on the ore?


Steel in principle is iron + carbon.


Are you? If so, why?


The leaf has 150-226 miles of range depending on the battery option. Even the first generation nearly a decade ago had more than 60.


I've heard that cold weather combined with high speeds and a very degraded battery and running the heater can leave some of them with an effective range around 60 to 80 miles.


You don't even need to have high speeds or heater usage. 1st gen Leaf's have 60mi range pretty consistently just because of how small the battery was, and how degraded they are.

In general the Leaf seems to be a bad buy, IMO, just because they do not have any liquid cooling. I don't know why they think they can get away with it... but literally every other EV manufacturer decided liquid cooling/heating is necessary for operating... but not Nissan.


I'd define being 'financially secure', as being confident that you will not need to make changes to your lifestyle for financial reasons. It makes sense that that depends pretty heavily on how expensive your current lifestyle is.


Right. It sounds funny to have a 2x guestimate from many people though. Is that evidence of a common mental heuristic for estimating and mitigating future risk?

I personally can think of a net worth figure which seems like it might be comfortable under lucky circumstances (no major crash or catastrophic health issue). And, right now I also feel like twice that would make me feel pretty secure. In spite of my concerns about the future unknowns, having that amount would probably cause me to essentially retire, turning my career into a hobby so I could shed the less enjoyable parts...


"2x" is the same thinking behind "if you don't have a backup for it, you only have it temporarily" , for anything "it" may be.

The thread starter is ambiguous about whether "secure" means "secure in what you currently temporarily have" vs "secure to have a reasonably acceptable life".


> "if you don't have a backup for it, you only have it temporarily"

Fabulous line. Is that attributable to anyone in particular?


Slate and ceramic tile roofs are good options - they are not combustable and will not melt. I'm not sure they would hold up to a 15 meter log landing on them, but they really do reduce the chance of your house burning.


Yes, true. Slate is not common in the west. Tile is, although I think faux-tile is getting common.


Highly flammable polymer faux-tile or somewhat-fire-resistant fiberglass faux-tile?


Fiberglass faux-tile sounds like "polymer with a nice wick embedded in it".


Facebook got money for the ads bought based on Cambridge Analytica's use of their API.


Correct.


The tricky part about this sounds like it would be specifying in the proxy service which parts of structured requests are responses are PII - how do you handle this?


In short, our REST based APIs are done via a YAML syntax, but our newer APIs are through Protocol Buffers.

See my other comment for more details https://news.ycombinator.com/item?id=16237349


I don’t have any recommendations for reading, but do enthusiastically recommend the korg volcas from the article - they are self contained, fun and intuitive to use, and very affordable. They sound good enough that you will continue to use them even if you have more expensive gear, and what you learn about synthesis transfers easily.


Be careful w/ these urls - I visited one and it appears my IP is now blocked from accessing yelp.com.


What do you suppose would happen if we all visited these URLs from every public access point we use? (edit: and shared VPNs, Tor, corporate networks, etc.)


That's really interesting. They might be trying to blacklist scrapers that don't properly respect robots.txt files.


Why would a scraper who doesn't respect robots.txt be accessing that file?


If I was building an unruly scraper (which, in case our new overlords are listening, I would never do), I would read robots.txt so that I had a clue where the secret information that the company did not want me to read was located.

I'm not allowed to look in /documents/source/? Perfect. Let's start there.


They might be using it as a way to find specific pages which have content Yelp doesn't want you to scrape. The "evil" scenario.

They might also not be looking at the file, and just appending random words to the end of Yelp's biz URLs to scrape every business. Which, at some point, it might hit that URL by accident, since they are all words you'd find in other business URLs. Though this seems less likely.


I assume the GP was using their browser to access these links, though they still be blacklisted by Yelp?


Scrapers can be pretty shady, so they're isn't a good way to ensure that web traffic is coming from a legitimate human using a browser. To the server it's all just bits on the wire.


I just visited all of them: the IP was not blacklisted


Worked on my laptop, but when I tried the same thing on my phone, I was not blocked. (even when I request the desktop version of the site)


Because they whitelist the exit IP for the phone network, else one person could block access for millions.


And what a great loss that is :-)


The statistic that stands out to me from this article is that 1 bitcoin transaction uses enough energy to power 5.58 us households for a day.

I'm hoping someone more knowledgeable about bitcoin can comment - is it likely that this will continue as the mining reward decreases? How expensive will transactions be after that happens? And if smaller rewards reduce total mining and power consumption, how vulnerable does the blockchain become to attack?

What i'm wondering is if transaction costs in the 'end state' of bitcoin can be competitive with centralized competitors like credit cards, paypal, etc. given this level of power consumption?


    I'm hoping someone more knowledgeable
    about bitcoin can comment
I did and was quickly voted to the bottom.

    bitcoin can be competitive with
    centralized competitors like credit cards
In it's current form it can't. It's already running at max capacity. No further increase in transactions per day is possible.

If there will be a cryptocurrency that can handle as many transactions as Visa, it will be something else then what we currently call Bitcoin.


Lightning network allows trustless instant and low fee payments. It is at the embrional stage yet, and the whole structure has yet to be defined, but the point to point protocol for trustless off-chain instant transactions is ready.


Iota?


Correct. Glad someone has heard of it at least on hacker news.


So, the block reward is indeed increasing, but two other things are increasing very fast. First is the price per Bitcoin, and second is the number of fees per block. Just the day before yesterday miners received 1800 coins from mining and an additional 500 from fees. That's already over 20% of the total daily reward. This two things are more than compensating the loss of block rewards (in BTC terms). Things aren't expected to improve based on this.

It's kind of insane if you compare to other payment services (if that's how you use BTC). Not only do you pay $5-$10 per transactions, but that transaction also consumes 20,000-30,000 times more energy.


Well, transaction costs are already super high. I made a transaction yesterday for $5 and it was single input/output. But it was urgent, so I paid generously.

As the network grows, the demand for transaction grows too. The fees will not increase because the reward decreases. Simply miners will stop mining as it is no longer profitable. But this will happen in 2090-2140. So it is very far.

I think in the future, lightning networks and centralized wallets will be the way to go. The blockchain will be used by only a few big guys and transaction costs will be over $100/tx.


Well... Right now we have blocksize limited to 1 mb. If we will remove this limit and Bitcoin becomes a global currency, we can earn a lot from transaction fees. nChain estimates about 0.05 for a transaction if it will became us big as VISA. If you interested where is one youtube video talking about possible fees.


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