> Bandwidth and processing are substantial bottlenecks with SAR; Only targeted and stationary applications have been broadly useful so far, and more focus has been put on planes than satellites for this.
I'm not sure why you assume this, this is factually incorrect. Satellite based SAR has been successfully used for civilian ship detection applications (traffic management, illegal fishing, smuggling detection, etc) for over three decades. I am sure its military use goes back much further.
> SAR is not as simple as taking a static image with a fixed resolution, your sensing window has got a target velocity and distance in mind and the antenna and processing needs to be tuned for that.
No? SAR satellites take thousands of SAR images of stationary scenes every day. It's true that object motion in the scene introduces artifacts, specifically displacement from true position - this is often called the "train off track" phenomenon, as a train moving at speed when viewed with SAR from the right angle will look like it's driving through the adjacent field rather than on the track. However, this isn't a significant problem, and can actually be useful in some situations (eg: looking at how far a ship is deflected from its wake to estimate its speed).
40 years ago the USN was working on using SAR with a elliptical kalmann filter to detect _submarine_ wakes. I assume things haven't digressed since then.
Eh, not really. Synthetic Aperture Radar satellites used for marine ship detection have extremely wide sensor swath widths, and ships show up as very bright radar targets against the ocean. Detecting a large ship, even in a very large search area, is almost trivial.
Identifying a ship is harder, but not insurmountable. In particular, large ships like aircraft carriers tend to have very identifiable radar signatures if your resolution is high enough.
How do these work? I would think radar would have a very difficult time seeing a ship against the backdrop of the ocean from so high above. Is the satellite bouncing radar waves off the side of the ship as the satellite is near the horizon? Even if you can detect a ship, I'm having a hard time imagining a sufficiently high radar resolution for such a wide sensor swath width at such an extreme range. Is the idea that you locate it with the wide sensor swath and then get a detailed radar signature from a more precise sensor?
Even with an extremely low resolution radar hit they are very identifiable.
Most naval vessels move in groups/squadrons. Carriers basically always travel with a "carrier strike group"/CSG of a dozen other ships and destroyers often travel in "destroyer squadrons"/DESRONs. So any time you see a cluster of hits, just by the relative responses of each hit you can narrow down and guess the entire CSG/DESRON in one go and then work out which responses map to which ship in the CSG/DESRON once you have a good idea of which group you are looking at.
This is especially true because ships even within the same class have varying ages, different block numbers, and differing retrofits. So each one has a unique signature to it.
But also if you aren't completely certain you can always come back with a second high resolution pass and then it's trivial to identify each ship just visually.
Granted, but how does satellite radar actually see ships at all? How do the ships not blend into the ocean (the relative difference between the distances between ship<->satellite and ocean<->satellite is minescule)?
Consider shooting a ray at the ocean at an oblique angle from a satellite: it bounces off and scatters away from you. Hardly any of the energy scatters back towards you.
Now, put a ship there. The ray bounces off the surface of the ocean and scatters up into the side of the ship, and from geometry, it's going to bounce off the ship and come straight back towards its original source. You get tons of energy coming back at you.
A ship on the ocean is basically a dihedral corner reflector, which is a very good target for a radar.
> I'm having a hard time imagining a sufficiently high radar resolution for such a wide sensor swath width at such an extreme range. Is the idea that you locate it with the wide sensor swath and then get a detailed radar signature from a more precise sensor?
That's one approach, there are so-called "tip and cue" concepts that do exactly this: a lead satellite will operate in a wide swath mode to detect targets, and then feed them back to a chase satellite which is operating in a high resolution spotlight mode to collect detailed radar images of the target for classification and identification.
However, aircraft carriers are big, so I don't think you'd even need to do the followup spotlight mode for identification. As an example, RADARSAT-2 does 35 meter resolution at a 450 km swath for its ship detection mode. That's plenty to be able to detect and identify an aircraft carrier, and that's a 20 year old civilian mission with public documentation, not a cutting edge military surveillance system. There are concepts for multi-aperture systems that can hit resolutions of less than ten meters at 500 km swath width using digital beamforming, like Germany's HRWS concept.
If only it could actually do anything. I genuinely don't understand how we refused to retrofit any weapon system to the gun mounts. We have 5inch guns. They aren't the magic cannon it was designed for but do they really not fit? Apparently we are now putting hypersonic missiles in those mounts instead.
A Zumwalt with 5 inch gun offers almost no mission capability above a simple coast guard cutter.
They're putting hypersonics on it because they've got 3 hulls and might as well get some value out of them, but not because it's what you'd design for from scratch.
The Zumwalt program was dumb from day 1. It was driven by elderly people on the congressional arms committees that have romantic notions of battleships blasting it out.
The reality is since the development of anti ship missiles, sitting off the coast and plinking at someone is suicidal, even if you have stealth shaping and uber guns of some sort.
The Zumwalt class are being refitted to carry CSP. And the boutique gun system is really a complex thing, it's not like packing in a bunch of VLS containers.
Just do a youtube search and you'll find plenty of talking head explainer videos. Ignore the talking head and just look at the imagery and data they share.
87 years ago, our founders launched a disruptive startup on this continent—a new nation built on the core values of liberty and the mission-driven proposition that "all men are created equal."
Right now, we’re facing a major pivot point in a great civil war, testing whether this organization, or any venture with such a strong culture and vision, can truly scale and endure. We’re currently on-site at a key battlefield of this conflict. We’ve gathered here to dedicate a portion of this space as a final resting place for the team members who gave everything to ensure the brand could live on. It’s the right strategic move.
But looking at the bigger picture, we can’t actually "brand" or "consecrate" this ground. The high-performers, both living and dead, who put in the work here have already established its value far beyond our ability to add or detract. The world won't remember our status updates, but it will never forget their execution.
It’s up to us—the remaining stakeholders—to stay dedicated to the massive project ahead of us. We need to take inspiration from these top-tier contributors and double down on the cause they were so passionate about. We are here to resolve that their efforts won't be a sunk cost; that this nation will undergo a digital transformation of freedom; and that a customer-centric government—of the people, by the people, for the people—will never be disrupted out of existence. #Leadership #Vision #Legacy #GrowthMindset
This is great. My only gripe is that it's still way too smart compared to most of the stuff I see on LinkedIn. If it had wrapped up with a "it's not X, it's Y", would've been perfect.
> Then again maybe the quality of Lincoln's literacy defies it.
I think so. My first thought reading this output is that I should ask the LLM to first write in the style of Lincoln and then slightly modernize the prose.
Anybody else being annoyed by all this focus on em-dash use to detect AI? In no time, the bad guys will tell their BS machines to avoid em-dashes and "it's not X it's Y" and whatever else people use as "tell-tale signs" and eventually the training data will have picked up on that too. And people who genuinely use em-dashes for taste reasons or are otherwise using expressions considered typical for AI are getting a bad rep.
This is all just demonstrating the helplessness that's coming to our society w.r.t. dealing with gen AI output. Looking for em-dashes is not the solution and distracts from actually having to deal with the problem. (Which is not a technical but a social one. You can't solve it with tech.)
This is turning out to be a huge issue for me as my frequent use of em-dashes makes my remarks trigger people effectively disrupting attempts to communicate. Maybe my communication needs to change or maybe these objections are yet another red flag to watch for.
> Anybody else being annoyed by all this focus on em-dash use to detect AI?
Yes, the “AI detectives” can be quite annoying, as the comments are always the same. No substance, just “has X, it’s AI”. The em-dashes detectives tend to be the worse, because they often refuse to understand that em-dashes are actually trivial to type (depending on OS) and that people have been using them on purpose since before LLMs.
Mind you, using em-dashes as one signal to reinforce what you already perceive as LLM writing is valid, it’s only annoying when it’s used as the sole or principal indicator.
I keep reading about students are learning to intentionally write worse so that it doesn't get flagged as AI-generated. I think it's a systemic problem that won't be solved in the short term, unfortunately.
It's hilarious that em dashes and "it's not X; it's Y" and other trivial things are the best way for humans to spot AI now. Like if AI robots infiltrated us, at first we'd be like "ooh, he has long ears, he's a robot". And after a while the robots will learn to keep their ears shorter. Then what? When we're out of tell-tale signs?
> We’ve gathered here to dedicate a portion of this space as a final resting place for the team members who gave everything to ensure the brand could live on. It’s the right strategic move.
This is hilarious but... and I can't believe Im actually giving critique here... but a modern day, LinkedIn version would be couched in words like "exceedingly complex", "multi-domain", "system of systems", etc.
But the whole thing is brilliant. And #GrowthMindset at the end is absolute gold.
What does it mean for two people to be "equal"? Obviously, it cannot mean they are equal in strength and in quality. There are people who are excellent, and excellent in many ways, and people who are mediocre or poor in quality in many ways. People are also morally diverse, ranging from the virtuous and the saintly to the thuggish and the depraved.
No, this equality is an equality of basic human dignity. It rests with human nature: our dignity is rooted in our rationality and freedom to make chose. Incidentally, this is also the basis for human rights.
Historically, however, most cultures did not believe in human equality or equality of dignity. You only see that with a robust account of natural law and in its fullness within the Imago Dei; living up to it is another matter. Liberalism [0], as an offshoot of this tradition, takes for granted this notion, but when pressed, it has trouble offering justification. That's why political appeals to equality now appear more frantic and strident. When there is an underlying uneasiness about the rational basis of one's convictions, this often transmutes into emotional defensiveness. But mere assertion has little force. Over time, emotion and pure assertion does not maintain its grip, which makes these quotes that much more interesting.
[0] Another fun case are materialists who simultaneously believe in equality. If there is anything that would dash the very notion of equality, it is materialism.
Their WAF isn't there yet, the moment it can build the expressions you can build with CF (and allows you to have as much visibility into the traffic as CF does), then it might be a solid option, assuming they have the compute/network capacity.
Many countries have solved this with a special background check. In Canada we call this a "vulnerable sector check," [1] and it's usually required for roles such as childcare, education, healthcare, etc. Unlike standard background checks, which do not turn up convictions which have received record suspensions (equivalent to a pardon), these ones do flag cases such as sex offenses, even if a record suspension was issued.
They are only available for vulnerable sectors, you can't ask for one as a convenience store owner vetting a cashier. But if you are employing child care workers in a daycare, you can get them.
This approach balances the need for public safety against the ex-con's need to integrate back into society.
Why are only some sectors "vulnerable" and who is to make that call? How about the person cooking my food?
You're over-thinking it, trying to solve for a problem that doesn't exist. No one has a "right" to work for me. There's plenty of roles that accept ex-cons and orgs that actively hire them.
Of course, I don't need to know everything, just if I'm hiring them I'd like to know if they have been tried and convicted of a crime, and then I can make a judgement whether it's disqualifying for my particular need.
I don’t think everything you’re saying is completely out of line, but the way you’re drawing a line in the sand and being so unequivocal about this is kind of striking. You won’t even entertain a more nuanced to approach to this.
Hardware should be much easier, especially if you get your boards fabbed and assembled at a CM (which you probably should, very few companies have a good reason to move assembly in-house).
All Canadian jurisdictions, as far as I am aware, are at-will employment. Unionized environments are an exception because they have layoff procedures in their collective agreements, but that's the same in the US.
Seems like a very bizarre move, considering Canadian-domiciled corporations have access to very generous financial incentives (SR&ED) at both federal and provincial levels.
Can't help but think this is a move meant to satisfy the US admin.
Again, I have no inside info, but I'm pretty sure it's got nothing to do with that.
Most Canadian YC founders incorporate their startups in the US (sctb and I did that, way back when), just like other international founders do and of course U.S. founders do, so the number of companies being affected by this change must be very small—small enough that it would be of little interest to the US govt.
Most probably the change is because the number was too small to justify all the paperwork, legal hoops to jump through, compliance tracking, etc., that inevitably come with cross-border investments. The startups that YC funds are almost always so early-stage that it ends up being easier for everyone if the founders just incorporate in the US. (It would be like a software team saying "why are we putting all this extra effort into supporting platform X when we only have 3 users on platform X and they can all easily switch to platform Y".)
But please understand that I'm just guessing here. The reason I'm posting at all is that I'd hate for any Canadian founders (or potential founders) to read a misleading headline and say "welp, I guess YC doesn't want us then". That is certainly not the case!
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I'm not sure why you assume this, this is factually incorrect. Satellite based SAR has been successfully used for civilian ship detection applications (traffic management, illegal fishing, smuggling detection, etc) for over three decades. I am sure its military use goes back much further.
> SAR is not as simple as taking a static image with a fixed resolution, your sensing window has got a target velocity and distance in mind and the antenna and processing needs to be tuned for that.
No? SAR satellites take thousands of SAR images of stationary scenes every day. It's true that object motion in the scene introduces artifacts, specifically displacement from true position - this is often called the "train off track" phenomenon, as a train moving at speed when viewed with SAR from the right angle will look like it's driving through the adjacent field rather than on the track. However, this isn't a significant problem, and can actually be useful in some situations (eg: looking at how far a ship is deflected from its wake to estimate its speed).
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