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User: Guspaz

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  1. Re: Economics of that stunt are dodgy on SpaceX Successfully Lands Its Rocket On A Floating Drone Ship For The First Time (theverge.com) · · Score: 5, Informative

    That's not really how rockets work. Sometimes a launch profile is compatible with secondary payloads, and so they sometimes do that. But often they're not, and so you can only launch to the one orbit. SpaceX doesn't control the satellite manufacturers operators: if the payload doesn't need the full payload, they can't just stick another satellite in there or tell them to make it bigger. If they could be putting additional payloads in the rocket to derive additional revenue, they would be. When they do the Orbcomm launches, they're launching lots of satellites at the same time, but then, those satellites all launch into very similar orbits.

    Reusability on the first stage doesn't add terribly much weight anyhow: it takes a lot less fuel to decelerate a mostly empty stage than it does to accelerate the whole thing up to speed in the first place. It's also not a 1:1 relationship: 1 kilo of extra fuel does not subtract 1 kilo of mass from the potential payload. That would be true of the second stage, but not the first stage.

    Since they can't really use that extra capacity anyhow, they might as well use it for cost savings, because reducing your costs is even better than increasing your revenue.

  2. Re: Economics of that stunt are dodgy on SpaceX Successfully Lands Its Rocket On A Floating Drone Ship For The First Time (theverge.com) · · Score: 3, Insightful

    Most of their launches don't require the full payload capabilities of the rocket. If they're not going to use the extra payload mass anyhow, how does that reduce revenue?

  3. Re:Windows Update on New Windows 10 Preview For PCs With Bash, Cross-Device Cortana Released · · Score: 1

    What does a touch screen have to do with anything? Win10 apps don't require touchscreens.

  4. Re:Nobody cares. on New Windows 10 Preview For PCs With Bash, Cross-Device Cortana Released · · Score: 1

    Windows runs a lot more than just bash too, since this isn't a port of bash, but an entire Linux kernel compatibility layer. It's basically reverse WINE.

    If you want to SSH into Windows after installing WSL, you type the same thing you would on your Linux box: "sudo apt-get install openssh-server"

  5. Re:Microsoft Linux on New Windows 10 Preview For PCs With Bash, Cross-Device Cortana Released · · Score: 1

    Windows only makes up 10% of Microsoft's revenue, and that's dropping. They literally gave away Windows 10 for free. They can survive just fine without any OS revenue.

  6. Re:Windows Subsystem for Linux? on New Windows 10 Preview For PCs With Bash, Cross-Device Cortana Released · · Score: 1

    "Windows Services for UNIX" was introduced 17 years ago, so "Windows Subsystem for Linux" is at least consistent with their prior naming for such things.

  7. Other provinces have major issues with corruption too. Ontario is in the midst of a developing scandal, where you've actually got lobbyists coming out in favour of campaign finance reform because they're tired of always getting shaken down for money by the Ontario liberal party.

  8. Why is it a problem? on Why BART Is Falling Apart · · Score: 1

    I get that being expensive means things cost more, but is it really all that big of a problem? Montreal's metro system is way more custom than BART, is nearly a decade older, and handles three times as many daily passengers on a system roughly a third as big, and upgrading/replacing stuff hasn't been presented like some sort of impossible task. Yeah, it means that when you buy new cars, they need to be custom designed. So... you hire a company to design them.

  9. Re:Efficiency on Google Challenge Results In Astoundingly Efficient Inverters · · Score: 1

    The inverters used for 120 kW+ charging isn't in the car, it's in the charging stations. The only charging stations hitting 120 kW+ are Tesla's superchargers, which are pure DC as far as the car is concerned.

  10. Re:Why the drone ship on SpaceX's Latest Launch Successful, But Ends With a "Hard Landing" (theverge.com) · · Score: 3, Informative

    It's all about the fuel. On launches that leave enough spare fuel, they actually return the rocket all the way back to a landing pad at the launch site in Florida. They successfully landed the rocket once in that manner. But on launches that require more fuel (to put a heavier payload into a faster orbit), there isn't enough fuel leftover for the burn that would send the rocket back towards the launch site. As a result, they are limited to a relatively ballistic trajectory from the launch site, which means landing somewhere out to sea. The landing destination is actually pretty precise (the drone ship is trying its best to stay stationary, not move to meet the rocket), it's just that it's the only place they have enough fuel to get to.

    The first stage of the rocket never reaches orbit: it's still going really really fast, but not orbital velocity. So after the second stage separates, left alone, the first stage would start falling down again downrange and crash into the ocean.

    Normally, after separation, the first stage flips itself over and then does a boostback burn to kill the forward momentum, and give it enough momentium backwards to line up its trajectory back towards the launch site. Then later it does a deceleration burn to slow itself down to keep the atmosphere from ripping it apart. And then finally, it does a landing burn for the last segment to slow it to a stop.

    On some missions, they don't have the fuel to do that full boostback burn, so they kill some of the forward momentum, but that's it.

  11. There was originally supposed to be enough fuel for the landing. The way it works is that they normally put the satellite in a transfer orbit, and then the satellite moves itself to the final orbit, kind of a third stage of the rocket. That's very slow, however. SpaceX was months behind schedule, so they promised to put the satellite into a much closer to final orbit to shave around a month off the required orbital maneuvering. Unfortunately, that used up the extra fuel reserved for landing.

    Had they not been so far behind schedule, then they would have had a much better shot at the landing. Unfortunately, SpaceX still has a serious problem with launch cadence: they just can't get the thing flying as regularly as they're supposed to.

  12. Re:Why does nobody... on SpaceX's Latest Launch Successful, But Ends With a "Hard Landing" (theverge.com) · · Score: 1

    Because it will basically never be cheaper than expendable rockets due to the massive R&D and construction costs, and by the time it was flying, it would be competing against other reusable rockets anyhow.

  13. Vulkan [...] [is] a replacement for OpenGL to make it more difficult to buy other people's graphics cards.

    Whose graphics cards? The graphics card vendors representing roughly 99.5% of the market support Vulkan, and the other 0.5% don't matter because their stuff is very old super low performance embedded chips that isn't useful for gaming anyhow.

  14. Not the first time... on Windows 10 Forced Update Resets Default Apps To Microsoft Products (theinquirer.net) · · Score: 1

    I've already had a Win10 automatic update reset all my file associations to the Microsoft apps before. How does this keep happening?

  15. Re:Kind of crippled there... on UK Company Riversimple Plans a Fuel-Sipping Hydrogen Car (techienews.co.uk) · · Score: 1

    We have smart cars here too, and they have a top speed of 125-130 km/h.

  16. Kind of crippled there... on UK Company Riversimple Plans a Fuel-Sipping Hydrogen Car (techienews.co.uk) · · Score: 2

    A car with the range for highway driving, which is incapable of traveling at highway speeds...

    It's got a top speed of 96 km/h, while typically highway speeds here are around 120 km/h with a speed limit of 100... Do you really need a car with almost 500km of range if the anemic top speed effectively limits it to surface streets?

  17. Last time Microsoft released a first person Halo game on PC? 9 years ago, with Halo 2, and even that was three years after the console version.

    Put your money where your mouth is, Microsoft.

  18. Re:Cats & dogs living together on Samsung's AdBlock Fast Removed From the Play Store (androidheadlines.com) · · Score: 1

    Try a different ad blocker, maybe? I've been quite happy with BlockBear. I must admit that it doesn't block all ads, but it catches the vast majority of them.

  19. Cats & dogs living together on Samsung's AdBlock Fast Removed From the Play Store (androidheadlines.com) · · Score: 0

    So, let me get this straight: Apple is encouraging iOS users to use ad blockers by adding explicit and specific support for them to Safari, while Google is trying to erase ad blockers from existence...

    I feel like I'm taking crazy pills!

  20. Re:Copyright on Ask Slashdot: Economical Lego-Compatible 3-D Printer? · · Score: 1

    You really don't need 0.005mm precision to get two plastic bricks to mate. Higher resolution 3D printers like the Form2 have a 25 micron layer height with a 140 micron laser spot. That's already overkill to make a LEGO-compatible brick.

  21. Re:They tried it before with Cablecards on Cable Lobby Steams Up Over FCC Set-Top Box Competition Plan (arstechnica.com) · · Score: 1

    While it sucks that they didn't support SDV in some cable cards (I'm assuming, CableCard is an American thing that we never had in Canada), SDV is really quite valuable from a technical standpoint. Cable systems tend to be really crunched for spectrum, and SDV lets them free up huge swaths of spectrum for DOCSIS (cable modem) use.

    Eventually, it seems like the trend is moving to IPTV over DOCSIS 3.1, which should solve the capacity issues by letting them use the entire spectrum for data, ultimately getting them reasonably close to GPON throughput.

  22. If it was shit wiring, then how come only the Cree bulbs have issues, while Ikea LED, Walmart LED, generic CFL, incandescents, and flourescent tubes have no issues?

  23. I started out with 15 fixtures with Cree bulbs. I suffered from 1 completely failed bulb, one bulb that randomly changed between full and half brightness (and so had to be replaced), one bulb that sputters frequently, and a few others that sputter occasionally. Some of these bulbs are relatively new (the one that sputters frequently was bought less than a year ago) while others are first-gen bulbs from when they first launched in Canada.

    Two other fixtures have Ikea LED bulbs in them, and have not had any issues at all. A few months ago, I replaced three of the Cree bulbs with Walmart bulbs, since one of the three Cree bulbs had failed, and Cree bulbs are very poorly diffused so it resulted in very unpleasant hotspots in the translucent fixture.

    My Cree bulbs are not all one kind. I've got 40W, 60W, 100W, and PAR. The 40W bulbs haven't had any issues that I can recall, while the 60W seem iffy, and the 100W seem pretty much gauranteed to fail quickly. None of these are in closed fixtures, and many of them are completely bare.

    So, you can imagine that my opinion on Cree bulbs is not all that favourable, having owned that many, and had that much trouble with them.

  24. I hope you kept that receipt, because I have not found Cree bulbs to be any more reliable than incandescents.

  25. Re: Cart before horse on SpaceX Plans Drone Ship Landing On January 17th (nbcnews.com) · · Score: 1

    Except they're not doing that they've announced that they're going to inspect it and then stick it on 39A and fire it up for a static fire. They do that for all flight rockets, put them on the pad and go through the entire launch process except at the point where a real launch would release the rocket they shut the engines off.