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cjensen

6,062 karma · joined September 29, 2011

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cjensen··on Finding the B-21's hangar location from the stars in its press image
You're right. Vandenberg, Kirtland, Canon, Altus, and Little Rock are all matches for the latitude and there is no text explaining them away. Even the "it must be California because Northrup" is both (a) debatable and (b) doesn't exclude Vandenberg.
cjensen··on Everything SBF is doing is in singular pursuit of not going to jail
Oh my goodness no! I'm not sure what SBF thinks he is doing, but he is definitely maximizing his chances of going to jail.

He is making his future defense lawyer's job very difficult by committing to a story. The lawyer will be severely constrained from suggesting alternate explanations of the facts to the jury because SBF has already negated so many possible interpretations. Every time SBF overstates an explanation, the prosecutors get that into the record. Every time SBF provably misstates or misleads in an interview, the prosecutors get to say "take a look at this slime ball."

When under investigation, you shut up. It's the only smart thing to do.

cjensen··on Apple blocks Coinbase Wallet
No because investments are not digital goods. Just because something is not physical does not mean it is digital. For example, a right to mine iron is not a physical thing, nor is it a digital thing; instead it is a legal thing.
cjensen··on Username cannot contain 'clyde'
In my experience, Apple devices readily respond to "Sarah" which was a top-five baby girl name in 19 of the years from 1980 through the 2000 [1].

[1] https://www.ssa.gov/oact/babynames/top5names.html

cjensen··on The RS-232 protocol [video]
Yep, referencing signals vs ground is the big flaw in RS-232. That's why a lot of industrial machinery uses RS-422/RS-485 which is sent as a differential pair. 422 gives you the same serial interface, the same signaling, but with a better physical layer that lets you send the signal on much longer runs.
cjensen··on The pool of talented C++ developers is running dry
New college grads who went to college right after high school. They have a strong intern program, so the students usually have some real-world experience using C++.
cjensen··on Why are so many babies born around 8:00 AM? (2017)
Hospitals and the medical profession have a lot of work, and for efficiency they stack the work up. A rule of thumb whenever dealing with a hospital is that everything will be massively later than you expect. It's a good idea to set your expectations ahead of time so that a bit of a wait does not take you by surprise. For a hospital procedure, half an hour late is pretty much right on time.

Congrats on the baby!

cjensen··on The pool of talented C++ developers is running dry
For anyone looking for a junior who knows C++ in Canada, we've had good luck with Sheridan College in Oakville ON.
cjensen··on Ask HN: What was being a software developer like about 30 years ago?
The big thing for me was address space size and computer sophistication.

DOS was still popular because it was so much cheaper than a workstation. Single-tasking means exiting your editor to do code check-ins and having to reload your context a lot. Networking was definitely an after-thought that many didn't have access to.

The bigger issue was the device you were programming. Small memory. Pointer sizes that might not be what you expect. Integers that overflow if you fail to think about their sizes. Pointers that cannot reliably be compared without normalizing them first. No threads. An operating system that does nothing other than provide access to files.

I've used C++ for my entire career. CFront 1.2 was a very different language than modern C++. Sometimes people wonder why I use stdio.h instead of iostreams: it's because stdio.h is basically unchanged since cfront and that code still works while and iostreams have changed significantly multiple times requiring re-writes.

One thing I miss is some of the color schemes in the Turbo Pascal/C IDEs. Yellow on Magenta and Yellow on Cyan were fantastic. I'm not sure why those color schemes don't work in GUIs -- I suspect it's because the geometry of fonts is so much different than text-mode graphics. Text mode had super thicc and clear fonts made out of so very few pixels.

cjensen··on Google added HEVC support in Chrome
New mpeg standards come out about once every ten years. It's amusing to me that Google are adding h.265 support six months after the approval of the next-generation h.266 standard[1].

[1] https://en.wikipedia.org/wiki/Versatile_Video_Coding

cjensen··on Available Today: Windows Dev Kit 2023 a.k.a. Project Volterra
HDMI connectors cost a lot of money to the HDMI licensing authority. This payment is very painful if you have a small quantity of shipments. DisplayPort is free. And as others have pointed out, you just need to buy a cable.
cjensen··on California Poised to Overtake Germany as World’s No. 4 Economy
Free college sounds good until you realize that only 30% of German students get to go. In California, it's 60%. Thanks to the community college system in the US, students who do poorly in high school get a chance to prove they can make it instead of having only one shot at admission.
cjensen··on California Poised to Overtake Germany as World’s No. 4 Economy
Yep, that's pretty much the entire reason.

This article is much like the "rich get vastly richer this year" stories that come out when the stock market rises. For some reason the opposite stories do not get written when the stock market craters because that's not "fun."

Expect "California falls to 5th place in the World's economy" articles if the exchange rate trend reverses.

cjensen··on Endonuclease fingerprint indicates a synthetic origin of SARS-CoV-2?
"Dog bites man" is not a story because it's just a thing that happens. "Man bites dog" is a story because it is surprising and not normal.
cjensen··on Heaviest element yet detected in an exoplanet atmosphere
Because Occam's Razor.

Absorption spectrums have never let us down, and are used all the time.

For this one place in the universe to have an exotic particle with an adsorption spectrum is pretty much impossible. To have an adsorption spectrum that is an exact mach for Barium is just adding a second impossible on top of the first.

Given the choice between something surprising and a doubly-impossible phenomena, the choice is clear.

cjensen··on New asteroid strike images show impact 'a lot bigger than expected'
They don't have a radar gun pointing at the asteroid which measures velocity. Instead, they have to measure position after a period of time to measure velocity. The smaller the change in velocity -- and this is a very tiny change -- the longer the time needed to measure the change.
cjensen··on OpenStreepMap 2012 vs. 2022
Not removed. Simply not visible at certain zoom levels. The render does a trade-off between what it can show. When they chose to add building footprints, it removed street names
cjensen··on OpenStreepMap 2012 vs. 2022
OpenStreetMap is very very good. In many ways, I prefer it to Apple and Google.

But the 2022 version suffers from a number of issues that Google and Apple are both suffering from recently: a lack of focus on who this map is for. Is this map ornamental? Or is it for driving? Walking? Finding tourist locations? What is it for?

One of the obvious changes in OSM between 2012 and 2022 is the addition of building footprints at the cost of removing a lot of street names. At this scale, do footprints really help? Am I planning a walk and need to know the street name where I will turn? When you are close to a destination, yes the footprints help one identify the correct building. But not here.

Here's a Google Maps example: if you put Canada's Yukon Territory into frame, does it show you the major roads? No. Does it show you any roads? No. Even if you select "traffic" it doesn't get the hint that you care about driving. It just wants to show you a map of geography.

And now an Apple Maps example: put California into frame. Freeways and two-lane roads are shown as thin lines that are nearly invisible. Good luck planning a route with this map! Want to go from Point A to B? It can do it! But want to consider side trips or general routing yourself? Nope.

There's still no adequate substitute for a AAA map for driving. I suspect hikers, bikers, and walkers are also poorly served by these non-specialized maps too.

cjensen··on Florida to Supreme Court: Let us regulate social networks as common carriers
Unambiguous good? No, it will depend on the quality of the moderation.

But I think it is more important to encourage good moderators to moderate more than it is to punish poor moderation.

cjensen··on Florida to Supreme Court: Let us regulate social networks as common carriers
Congress passed a law to specifically ensure they are websites are not responsible for the speech they reproduce. This law is good because it encourages content moderation because there are never consequences for the moderation decisions.
cjensen··on Head-On Crash: 2009 Chevrolet Malibu vs. 1959 Bel Air (2009)
If you step through the video with the "," and "." keys, you'll see that the steering wheel ends up in contact with the drivers seatback. A seatbelt that holds the driver in place doesn't help if there is no safe space for a body.
cjensen··on Can We Throw Satellites to Space? [video]
Suppose you have an object that has just left the atmosphere, and suppose it is in an orbit. You have the same problem again: every orbit repeats, so the object's orbit, having just left the atmosphere, will repeat into the atmosphere.

Let's put this another way: every orbit is an ellipse. If you do not alter your orbit, you will only travel on the ellipse. The moment you stop interacting with the atmosphere, you are on a fixed ellipse. The problem is just behind you on the ellipse is the atmosphere, and if you continue forward on the ellipse you will inevitably come back to the part of the ellipse that is still in the atmosphere.

cjensen··on Can We Throw Satellites to Space? [video]
The LEO post-launch force you link to is for minor orbital changes. Or large changes over a large amount of time. The problem with an orbit that begins at the ground is that you have exactly one orbit's worth of time in which to convert it into a real orbit. Magnetic or ion propulsion won't cut it.

My comment about solid rockets is due to the fact that they include fully combustable fuel in a ready-to-use mix. Solid rockets don't require much input to get them to combust. I assume no one is considering solid rockets for this application; I only mention it as part of assuming they would need a liquid rocket so I could explain the problem with liquid rockets which rely on pumps and pipes.

cjensen··on Secret talks that could have prevented the Apple vs. Facebook war
Are you trying to say that the poster I replied to, who specifically linked to a Wikipedia article about US Anti-trust Law, was not literally referring to US Anti-trust Law? And that I am being pedantic for assuming the parent poster meant what they said about the law they linked to?

Did you perhaps mean to respond to a different comment?

cjensen··on Can We Throw Satellites to Space? [video]
You can't fire anything into Earth orbit. Once propulsion is complete, you are in an orbit. Orbits repeat. So if your orbit starts from the ground, your orbit will intersect the ground which is... undesirable.

Instead, you have to fire a rocket motor to alter the initial orbit into one that doesn't intersect the ground. Now you have a new problem: you have to design a rocket motor which can withstand the launch. A solid rocket almost certainly will spontaneously RUD when heavy acceleration is applied. A liquid rocket has pumps and pipes which are likely can't survive the acceleration.

This is the reason spin launch is nonsense: you've traded a solved problem (make big rocket motor) for an unsolvable problem: make a rocket motor which can withstand absurd acceleration.

The other red flag with spin launch is that genuinely new approaches to problems do not come from unqualified randos thinking about a problem. For example, if a company has a crazy new idea for blood testing, it's really bad if the crazy new idea came from someone with zero experience and zero domain knowledge.

cjensen··on Secret talks that could have prevented the Apple vs. Facebook war
If Marriott and Best Foods work together to increase both profits, that's not an anti-trust violation just because they work together. The article you cite enumerates a number of categories of violations, but you haven't identified which one you think "working together" inherently violates. My guess is you are talking about Monopolization, but since neither Facebook nor Apple is a monopoly, and since Facebook and Apple do not compete against each other, I'm not sure how that fits.
cjensen··on Tracking 30 Years of Sea Level Rise
Yes with a but: the article says over the last 140 years the rise was 21-24cm, and the last 40 years saw a rise of 10cm. That strongly implies an acceleration of sea level rise that is more than any measurement error could account for.

I dislike climate models for my own personal reasons... but they do predict continued acceleration. For example, in 2019 the IPCC predicted that by 2100 (80 years) the level would rise an additional 0.6-1.0 meters.

So the prediction is accelerated rise, and is backed up by observed recent acceleration.

A 3' increase in max high tides would probably cause some issues.

cjensen··on Tracking 30 Years of Sea Level Rise
The max is 60-70 meters if everything including Antarctica melts. A full melt of Antarctica is not, as far as I know, a prediction being made by any model in the next thousand years.
cjensen··on SSD drives’ 40k-hour “death bug” continues to catch enterprises unawares
For an SSD, you need to buy "Enterprise" or "Data Center" class drives for this kind of application. That class of drive have higher write endurance which is important since enterprise applications can have orders of magnitude more writes to their drives than a typical desktop.

That said, there's no real standard blanket vendor recommendation so long as the "Enterprise" criteria is met.

cjensen··on The inventor of ibuprofen tested the drug on his own hangover
Doctors routinely tell patients to use way above the maximum OTC dose when instructing them on how to treat difficult muscle problems like back problems. (Please don't do that except under specific instruction).
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