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Unless some radical change happens to laptop power supplies in the next few months - a change from designs that have remained the same for over a decade - it's very likely this adapter will work with the newest (normal) laptops available when it comes out.

Also, laptops have very flexible power input circuits that will accept a wide range of DC input: they'll start running from ~12V (the voltage of an almost-dead battery), and go as high as the voltage specs on the input components allows - 25V (filter caps) is the usual absolute upper limit. Higher voltage means lower I^2R losses but manufacturers like to leave some safety margin, which is why 20V is somewhat of a de-facto standard given the parts available. The general power distribution circuits in a laptop are like this: there's a main power rail, whose voltage varies with battery voltage when running on battery, and is the DC-IN voltage with the adapter plugged in. The voltages for the CPU, GPU, chipset, etc. are all generated by DC-DC converters supplied from this main rail. There's a set of diodes/MOSFETs that wire-OR together the battery and DC-IN to the main rail, preventing current flow in the wrong direction. It also powers the battery charger.

I've read a lot of laptop schematics, and all of them use very similar power circuitry, often with the same components. The only real concern with device compatibility is in the ID schemes that some manufacturers use, either to "lock out" third party adapters or encode wattage selection. The simplest ones are nothing more than a resistor in the plug, different values for different wattages (IBM/Lenovo is one example). More complex ones use a 1-wire interface to an EEPROM or other storage element (Dell, Apple) (http://www.laptop-junction.com/toast/content/dell-ac-power-a... http://www.righto.com/2013/06/teardown-and-exploration-of-ma... ). Then there's all the others that have no ID at all, just +/- input, and these are the most compatible.

About the Dart itself: the technology used here (VHF SMPS) has been around for a long time in military/aerospace applications, where size/weight is more important than reducing switching losses.

http://www.eevblog.com/forum/crowd-funded-projects/vhf-lapto...


I would be skeptical of correlated variables that defy logic.

Butterflies numbers in North America likely have some correlation with dementia in New Zealand, but that does not imply causation.


Background: We had rescued a baby sparrow with an injured leg. There was no way to return it to its nest (it was at the nestling stage), and we'd already seen dozens die and not a single one get rescued by the parents after falling throughout the years (zerg rush of very big ants; cats; other insects) so we made the call to try and rehabilitate this one (there were no wildlife rehabilitators where we lived at the time).

She thrived and reached a point where she could be released, which we tried to do. She took it as us teaching her how to fly, and kept circling back and then looking at us like "hey guys, what do we do next?" After a bit of flying lessons she'd go back into her cage and sit in the back corner, away from the door, and after a while we'd have to bring the cage back into the house. After trying this a few times over a few weeks it became clear she had no intention of leaving, and she was starting to show social behavior towards us. She loved our routine. I would sit close to her cage whenever we ate, and she'd come up and eat at the same time. If we were late, she'd perch on the food thing and try and make eye contact with us (not eating until we did).

One time she produced a sort of "emergency" chirp. I had never heard it before yet it worked and made me realize she was calling for help. I went over to check on her, and she was sitting in the back corner of her cage, looking concerned. The large cage door had been stuck in the open position back when one of us was changing her food. I closed it and she was relieved.

One day I sat in a different place from usual and she was unhappy about it. She kept trying to get as high up in her cage as possible in order to get a look at me and make eye contact. She didn't eat very much and was looking a bit concerned. She was relieved again when I got up and talked to her. Later on we made sure not to change the seating arrangements.

Her ability to interact with us was on the same level as one of the more intelligent dog breeds. She would sometimes play games with us. Sparrows can be cheeky. Her bed time was a sort of game. We'd say the magic words and she'd understand, so she'd go into a corner of her cage and when we'd cover it with a piece of cloth, that'd be the darkest part. The bottom of her cage was transparent so she'd look at us through the plastic and swipe at it with her beak, like the normal beak-cleaning routine birds did. But she'd do it repeatedly (10+ times) whenever she was happy, and she loved when we got close to the cage and made eye contact through the plastic as she snuggled for bed.

Another time she made a unique kind of sound, designed to attract our attention. I went to see what that was about, and she made eye contact with me. She picked up a small piece of hardened bread (we fed her bread and it would get hard after a while) and dunked it in the water, and gobbled it down while looking at me. She was proud of her discovery that you could make hard bread edible again, and wanted to show it off.

She lived with us for about 20 years and sadly died of old age in August of 2016.


Fear not, among the millions of flags firefox exposes in about:config there is browser.link.open_newwindow.restriction that does exactly what you are looking for! Make sure to set it to 0.

Probably the most brilliant contributor to the art of sound design is a guy called Walter Murch. He's somewhat of a polymath in film, as he not only designed the sound for The Godather trilogy and Apocalypse Now, but he also edited the picture.

Anyway, Murch put a lot of his thoughts about both editing and sound into a book called 'In the Blink of an Eye', which is still read by film students today. One passage that always stuck with me is an informal rule that Murch gave himself after he discovered something odd about the interplay between sound and audience immersion. After a lot of experimentaiton, Murch found that in any 'moment' of a film (say 3 - 7 seconds), an audience can only process 2-3 layers of sound playing at once.

For example, Michael Corleone goes to meet Moe Greene and they're walking through the lobby. We hear footsteps, the elevator ding, and the atmos of the hotel. If Murch had added the sound of he luggage of the bell-boys or some guests arguing in the rooms, it would be too overwhelming for us and the verisimilitude of the film would become compromised.

I guess I'm mentioning Murch because this informal sound rule was always independent of speech from the actors, which he doesn't treat as a layer of sound. To me, this may be a very practical example of what these researchers seem to be finding: that there is indeed some parallel processing going on with speech and sound in our auditory cortex.


I don't use Twitter, so this is new to me, but I found this to be interesting because it's not your standard blog post turned into a tweet storm; it's a livestream over text. It's an altogether different experience. I rarely see a livestream over text.

> anyone who says we should "listen to science" needs to open a history book. dogma, dogma, dogma

You're describing humans.

What makes science novel is its mechanism for challenging and disproving blowhards without tipping into anarchy. That makes dogmatic incumbents' positions less stable while, remarkably, maintaining the integrity of the system as a whole.

Science doesn't (or shouldn't) claim to negate our worst instincts. Simply to uniquely check them through its method.


This is mind blowing:

> For the first half of the twentieth century, the going theory was that the invading element—the “antigen”—served as a template around which a corresponding antibody was molded. Only in 1955 did scientists discover the much stranger truth. It turned out that the cells that produce antibodies—called B cells, because they were first discovered in the bursa of Fabricius, an organ that does for birds what bone marrow does for humans—can produce only one kind each. Its structure is random, and nearly every B cell is discarded unused. If, however, an antibody created by a B cell happens to match some part of an antigen, that B cell will not just survive but clone itself. The clone incorporates many mutations, which offer the possibility of an even better match. After a few generations, an antibody with the best fit is “constructed” through a process of mini-evolution that occurs continuously in our lymph nodes and spleen. (Our ancestors the bony fish adapted the machinery of the B-cell system from an even more ancient parasite.)

So, natural selection discovered a way to run an embedded natural selection search process in an individual. Talk about meta.


If you're looking for a bit more flexibility around the current and voltage setting as well as a more solid mounting option and safety features, take a look at fpx board [1]. fpx is open source.

Disclosure: I'm the author

[1]: https://fpx.oxplot.com/


Threads about recycling have started to pile up just like the recycling has. A list of the major ones is below (but only with "recycl" in the title—if you find more, let me know!)

Given the current picture, perhaps most interesting in retrospect is this 1996 article (which apparently set a record for hate mail) and its sequel from 2015:

https://news.ycombinator.com/item?id=9757853 Recycling is Garbage (1996) (55 comments) - https://archive.is/JKG7y

https://news.ycombinator.com/item?id=10327585 The Reign of Recycling (34 comments) - https://archive.is/o8LBm

---

2020 https://news.ycombinator.com/item?id=24454067 Oil Companies Touted Recycling to Sell More Plastic (232 comments)

2020 https://news.ycombinator.com/item?id=24441979 How Big Oil Misled the Public into Believing Plastic Would Be Recycled (310 comments)

2020 https://news.ycombinator.com/item?id=24440516 Pringles tube tries to wake from 'recycling nightmare' (394 comments)

2020 https://news.ycombinator.com/item?id=23040674 Plastics pile up as coronavirus hits Asia recyclers (19 comments)

2020 https://news.ycombinator.com/item?id=22927072 'Horrible hybrids': the plastic products that give recyclers nightmares (40 comments)

2020 https://news.ycombinator.com/item?id=22741635 Industry spent millions selling recycling, to sell more plastic (105 comments)

2020 https://news.ycombinator.com/item?id=22467015 Coke and Pepsi are getting sued for lying about recycling (170 comments)

2020 https://news.ycombinator.com/item?id=22318165 Is Recycling a Waste of Time? (94 comments)

2019 https://news.ycombinator.com/item?id=21837414 Recycling Rethink: What to Do with Trash Now China Won’t Take It (152 comments)

2019 https://news.ycombinator.com/item?id=21742196 The Great Recycling Con [video] (77 comments)

2019 https://news.ycombinator.com/item?id=21303618 How Coca-Cola Undermines Plastic Recycling Efforts (132 comments)

2019 https://news.ycombinator.com/item?id=21297639 All plastic waste could be recycled into new plastic: researchers (150 comments)

2019 https://news.ycombinator.com/item?id=21102560 We asked three companies to recycle plastic and only one did (64 comments)

2019 https://news.ycombinator.com/item?id=21043986 Exposing the Myth of Plastic Recycling (17 comments)

2019 https://news.ycombinator.com/item?id=20762789 Plastics: What's Recyclable, What Becomes Trash and Why (215 comments)

2019 https://news.ycombinator.com/item?id=20728911 Smart plastic incineration posited as solution to global recycling crisis (84 comments)

2019 https://news.ycombinator.com/item?id=20726689 'Plastic recycling is a myth': what really happens to your rubbish (63 comments)

2019 https://news.ycombinator.com/item?id=20549804 Americans' plastic recycling is dumped in landfills (282 comments)

2019 https://news.ycombinator.com/item?id=20433851 Landfill is underrated and recycling overrated (336 comments)

2019 https://news.ycombinator.com/item?id=20134641 I work in the environmental movement. I don’t care if you recycle (15 comments)

2019 https://news.ycombinator.com/item?id=19889365 Why Recycling Doesn't Work (216 comments)

2019 https://news.ycombinator.com/item?id=19844551 Reycling Plastic from the Inside Out (46 comments)

2019 https://news.ycombinator.com/item?id=19799348 Bikes, bowling balls, and the balancing act that is modern recycling (2015) (35 comments)

2019 https://news.ycombinator.com/item?id=19728391 Just 10% of U.S. plastic gets recycled. A new kind of plastic could change that (116 comments)

2019 https://news.ycombinator.com/item?id=19483074 America Finally Admits Recycling Doesn’t Work (35 comments)

2019 https://news.ycombinator.com/item?id=19399543 The World's Recycling Is in Chaos. Here's What Has to Happen (25 comments)

2019 https://news.ycombinator.com/item?id=19346342 What Happens Now That China Won't Take U.S. Recycling (219 comments)

2019 https://news.ycombinator.com/item?id=18893252 The Era of Easy Recycling May Be Coming to an End (84 comments)

2018 https://news.ycombinator.com/item?id=17841584 Recycling in the United States is in serious trouble. How does it work? (94 comments)

2018 https://news.ycombinator.com/item?id=17677698 Trash piles up in US as China closes door to recycling (272 comments)

2018 https://news.ycombinator.com/item?id=17495872 Californians love to recycle, but it's no longer doing any good (14 comments)

2018 https://news.ycombinator.com/item?id=17409152 Plastic recycling is a problem consumers can't solve (441 comments)

2018 https://news.ycombinator.com/item?id=16856246 An enzyme that digests plastic could boost recycling (122 comments)

2018 https://news.ycombinator.com/item?id=16174719 Plastics Pile Up as China Refuses to Take the West’s Recycling (71 comments)

2017 https://news.ycombinator.com/item?id=15888827 Recycling Chaos in U.S. As China Bans 'Foreign Waste' (233 comments)

2017 https://news.ycombinator.com/item?id=15528740 China Bans Foreign Waste – What Will Happen to the World's Recycling? (63 comments)

2016 https://news.ycombinator.com/item?id=11083898 Is it time to rethink recycling? (147 comments)

2015 https://news.ycombinator.com/item?id=10327585 The Reign of Recycling (34 comments)

2015 https://news.ycombinator.com/item?id=9757853 Recycling is Garbage (1996) (55 comments)

2014 https://news.ycombinator.com/item?id=7778956 Is Recycling Worth It? (13 comments)

2010 https://news.ycombinator.com/item?id=1186666 Recycling is Bullshit; Make Nov. 15 Zero Waste Day, not America Recycles Day (18 comments)

2009 https://news.ycombinator.com/item?id=937097 The Recycling Myth (36 comments)


> "We've just made an offer to a new writer", [Chris Espinosa] told [me (Andy Hertzfeld)], "someone who I think will do a much better job on the technical side of things, since she used to be a programmer. Her name is Caroline Rose. I'm going to assign her to the window manager documentation and see what you think."

> The next week I sat down to meet with Caroline for the first time, and she couldn't have been more different than the previous writer. As soon as I began to explain the first routine, she started bombarding me with questions. She didn't mind admitting it when she didn't understand something, and she wouldn't stop badgering me until she comprehended every nuance. She began to ask me questions that I didn't know the answers to, like what happened when certain parameters were invalid. I had to keep the source code open on the screen of my Lisa when I met with her, so I could figure out the answers to her questions while she was there.

> Pretty soon, I figured out that if Caroline had trouble understanding something, it probably meant that the design was flawed. On a number of occasions, I told her to come back tomorrow after she asked a penetrating question, and revised the API to fix the flaw that she had pointed out. I began to imagine her questions when I was coding something new, which made me work harder to get things clearer before I went over them with her.

https://www.folklore.org/StoryView.py?story=Inside_Macintosh...


There is a rather famous blogpost by Bret Victor on this topic http://worrydream.com/ClimateChange/

> Order your thoughts. Keep it short. Communicate one idea in one sentence. etc. etc. etc.

This is true in general. I remember when I did consulting interviews you needed to talk like that and the feedback I got was that I didn't do enough of it.

Funnily enough, I could clearly tell that whenever I had a programmer job interview, everyone was always really impressed with how 'structured my thinking' was.

Other than being impressed the biggest benefit that you also describe in your blog post is that it is simply very clear what you are about! And people seem a lot happier when listening to you feels like a simple thing to do.

Here's an example of how I do it. The following that I wrote down was typed as quickly as possible.

---

Interviewer: So tell me about yourself

Me: Alright, there are three perspectives I'd quickly like to touch:

1. Personal

2. Educational

3. Professional

With 1. personal, I'm all about fantasy and curiosity. Understand that and you understand me.

Educational: I studied to become the bridge between the business world and the computer world while also trying to become an expert in both. Therefore, I started of with business informatics. Upon graduation I immediately started studying psychology - people, and computer science - computers. And I studied game studies to merge them back into one topic again.

Professional it's rather interesting: the past 8 years I saw my university as a playground and I just applied to any job that didn't feel like work. This resulted in me becoming a teaching assistant, a coach for teaching assistants, a bootcamp instructor and a programmer/web developer. In total I have about 2.5 years of work experience, 1.5 on teaching development and 1 on development.

---

It was a huge improvement compared to my standard 15 minute answer. This answer above is just told under 1 minute.


Sure. I didn't figure this out, but was relatively close to the investigation. My team provided a lot of data that ended up being used to come to root cause.

My team and extended teams managed almost 200,000 network devices, spread all over the world, most of which were Cisco, and most of which were installed in stores. And most of the switch ports were connected to customer facing Point Of Sale devices. Among these are employee facing registers and customer facing card scanners. That is, the devices you interact with whenever scan your card to pay for something.

With that many devices in that many locations in a largely unmanaged environment (the switches would be installed all over the store, often in the ceiling, and many of them experienced extreme temperatures), there were a constant stream of failures. The process to manage these failures was optimized, streamlined and largely automated.

However, it was discovered that switches were failing far more frequently in the northern Midwestern US than elsewhere, and then only in the winter.

So this wasn't a really big operational issue, but it had a substantial cost impact, and the rate was high enough that a lot of the affected stores did notice and were complaining.

Right. Very strange, very mysterious.

So, briefly, the root cause:

Apparently, people in the upper Midwest wear wool to stay warm far more frequently than other cold places, specifically the US northeast. And much of the time, the humidity is quite low. So, you have a lot of people wearing a lot of wool in low humidity air. These people generated a lot of static, which they would all too often discharge while interacting with the customer facing point of sale device. And, all too frequently, that pulse of static would end up flowing all the way back to the switch, often killing it.

I didn't follow the subsequent remediation efforts, so I don't know what if anything was done about that.


We don't donate to OSS software which we use, because we're legally not allowed to.

I routinely send key projects, particularly smaller projects, a request to quote me a commercial license of their project, with the explanation that I would accept a quote of $1,000 and that the commercial license can be their existing OSS license plus an invoice. My books suggest we've spent $3k on this in 2015. My bookkeeper, accountant, and the IRS/NTA are united on this issue: they don't care whether a software license is OSS or not. A $1k invoice is a $1k invoice; as a software company, I have virtually carte blanche to expense any software I think is reasonably required, and I think our OSS is reasonably required.

I would do this more often if OSS projects made it easier for me to do so. Getting me to pay $1,000 for software is easy; committing me to doing lots of admin work over the course of a week is less easy. Take a look at what e.g. http://sidekiq.org/ , which is an OSS project with a commercial model, does. Two clicks gets me to a credit card form. If I actually used Sidekiq, Mike would have had my credit card on file the day that form went up.


I have worked with a small number of exceptionally talented individuals (I don't know where to draw the "genius" line, but they were up there), and I see negative aspects of their personalities echoed in Stephen Wolfram. It looks like ego to me. People lose their humility after being told that their better than everyone else for their whole lives.

Being an expert at one thing doesn't make you an expert at everything. But it's hard to realize that when you're king of your world.

A different perspective. Highly creative (smart) people are those who make mental connections that others do not see but which exist. Crazy people are those who make mental connections that others do not see and which don't exist. Perhaps he sees the Wolfram language is superior in some way that doesn't actually exist, or perhaps we're not seeing something that does.


It certainly is a frequently asked question. But spelling everything out is against the spirit of the site.

On HN it's good for readers to have to work a little, and the audience is smart enough to figure things out.


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