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Comment: Re:Ah, PDP8 (Score 2) 92

by kenaaker (#49358185) Attached to: Rebuilding the PDP-8 With a Raspberry Pi
We had a PDP 8/I that the EE guys built a high speed paper tape reader for. One I/O addresss made it go forward, the other backward. Watching various sort algorithms run against data on the tape were educational in a unique way.

We also had a paper tape based 4K 2Pass Algol compiler that worked, it waited until you reloaded the freshly punched tape of intermediate format to start the next pass and gave you an loadable paper table on the final pass.

Not bad for a machine that had 8 Opcodes.

Comment: Re:The future of the Internet is Television? (Score 2) 271

by kenaaker (#49047121) Attached to: Peak Google: The Company's Time At the Top May Be Nearing Its End
Really wishful thinking. While we're seeing articles about "cutting the cable" and binge show watching (without commercials). The television advertising groups are trying to convince their customers that everyone wants to be like television. I spend time and money avoiding commercials, because they waste my life-span.

Comment: Re:why? (Score 1) 677

by kenaaker (#49043023) Attached to: Empirical Study On How C Devs Use Goto In Practice Says "Not Harmful"
Of course I understand. Mostly from having to debug and fix some of the multitude of ways that sort of "pattern" gets bollixed up. The biggest source of bugs in that instances of that pattern is the disconnect between the statements preceding each goto and the statements after the label. Do you have multiple labels? A label for each potential failing resource? An unwound set of labels? What convention are you using for the labels?

Or, the another possibility is recording everything that needs to be cleaned up. That introduces more state data that has to be initialized, maintained in a coherent state and cleaned up.

Now suppose that you have to change the order of setup because of a newly discovered hardware restriction. You potentially have to re-order the labels for your gotos, or which cleanup gets done after each label.

If the cleanup is done at the bottom of every block that is executed because of success, it is automatically done in the proper time and place.

Comment: Re:They are going big into alternative energy (Score 1) 163

by kenaaker (#48350491) Attached to: The Military's Latest Enemy: Climate Change
That process is already running in pilot plants in Germany. They're generating methane using a Sabatier process driven by excess renewable energy. The methane is injected into the national natural gas pipeline network. Typically national natural gas pipeline systems have a buffer of several days to weeks of supply.

The Wikipedia article is labeled Power to Gas There's a section for hydrogen and another section for methane. And of course, once you have methane and CO, you have feedstock for Fischer-Tropsch processes that provide liquid fuels.

Comment: Re:Existence of this... (Score 1) 451

by kenaaker (#48264337) Attached to: Ken Ham's Ark Torpedoed With Charges of Religious Discrimination
While it isn't completely impossible for some sort of coating material to have solved the problem, it would be inventing technology that was almost certainly unknown at the time.

In the 1800s even under the copper plating, the seams were caulked with oakum soaked in pine tar, driven in place with a caulking mallet and a caulking iron, putty was then applied to the hull seams and the deck seams were payed with melted pine pitch. The weather deck of the ship had to be as water-tight as the hull or waves breaking over the deck would founder the ship in short order. That's another thing that the typical Ark description gets wrong.

The pictures I've seen of the interior of modern Ark replicas look more like barn framing than ship framing. Wooden cargo ship frames from the 1800s were large. For example, the Flying Cloud had floor timbers (think ribs) that were sided(along the length of the ship) 12 inches, moulded (outside to inside) 17 inches at the keel (typically white oak or live oak), space between the frames was typically the same as the sided dimension (12 inches in this case). The keel of the Flying Cloud was 3 layers of rock maple, moulded 44 inches, and sided 16 inches, with additional keelsons and sister keelsons, the ship was nearly 9 feet through the backbone. And, it was all bolted through and through with 1 1/4 inch copper and iron bolts. Even the garboard strakes (outside hull planks) were from 4 1/2 inches to 7 inches thick, The ceiling (inside hull planks) was a minimum of 4 1/2 inches up to 7 inches thick. Most of the planking and ceiling were southern pine.

Comment: Re:Existence of this... (Score 1) 451

by kenaaker (#48260217) Attached to: Ken Ham's Ark Torpedoed With Charges of Religious Discrimination
The key phrase that describes something the purported size of Noah's Ark built from wood, is "Works like a wicker basket".

If you can't keep the hull from flexing, every time a section of the hull passes over a wave the frames and strakes will bend, the seams will open, and the sea will come in. Then, unless you have high volume bilge pumps running constantly, down the ship goes.

Comment: Re:100 year old survival knowledge in PDF files??? (Score 1) 272

by kenaaker (#48251431) Attached to: A Library For Survival Knowledge
That depends on whether you know where the stored reading glasses are. I spent a couple of hours one time searching for my glasses because I hurriedly put them on top of the refrigerator and then couldn't see well enough to spot them. I felt a lot of sympathy for that character when I saw that episode again.

Comment: Re:I still don't see what's wrong with X (Score 2) 226

by kenaaker (#48171677) Attached to: Lead Mir Developer: 'Mir More Relevant Than Wayland In Two Years'
Someone above mentions exporting a video stream to handle remote sessions. I think that's actually a strong contender for a new User Interface system, but it discusses nothing about how that actually happens.

It the GPU exports an MP4 video stream that can be delivered directly to any display (local or remote) that deals with the last connection bottleneck. It's a standard, its ubiquitous, and its implemented in hardware. The return channel for user interaction needs to be done, but that doesn't have the performance issues that the presentation does.

The other piece of the system that needs to be handled is the API for the interface to the GPU hardware. A contender for that seems to be an API tied to EGL ES (if I read the acronyms right), and there should be others. That assumes the Khronos Group is doing something useful there. How many implementations are there of EGL ES to GPU hardware drivers?

The layer in the system between the user applications and the hardware interface is the place where QT, GTK, Windows graphics api, and all the other graphics toolkits go. Those toolkits shouldn't care too much about the hardware details, just the published capabilities of the GPUs.

Just some thoughts

Comment: Re:Seems incorrect (Score 2) 80

by kenaaker (#48115811) Attached to: NVIDIA Presents Plans To Support Mir and Wayland On Linux
It seems like there's a strong possibility that the replacement for remote X-Windows could be something conceptually simpler but could require one massive block of processing. (And I think Nvidia is most of the way there).

The remote presentation could all be done with an mpeg 4 stream, direct from the GPU. That chooses one standardized mechanism for presentation, and I think it should be sufficient for almost any sort of application. The presentation space in the GPU would be written with a number of APIs, but as the time came to present that image to the user, the GPU would transform the presentation space into an appropriate mpeg 4 frame and push it out some serialization interface for delivery to the end device.

The only additional interface required is for the user input device, which is non-trivial, but doesn't require the brute processing capacity that presentation requires.

Speculation, I know.

Comment: Re:This just illustrates (Score 1) 365

by kenaaker (#47342027) Attached to: Germany's Glut of Electricity Causing Prices To Plummet
Comfortable as in sheltered, warm in the winter, fed any time I feel like it any time of year, and dry when a thunderstorm has knocked out the power and is dumping on us.

To restate. Critical being the heating boiler (LP), some lights, the kitchen (except the electric oven), a sump pump, and a circuit for the living room and master bedroom. I grew up without running water and with wood stove heat. The current setup is way better than that. And it does last for days without starting up the generator.

Comment: Re:This just illustrates (Score 5, Informative) 365

by kenaaker (#47340485) Attached to: Germany's Glut of Electricity Causing Prices To Plummet
Sure, the inverter/ATF is a Xantrex SW4048. The model has been replaced with other models. I've never had a problem with it, although I've heard some complaints about components in the newer models. The main service tie is a 30 amp 110 circuit, and there's a secondary input that I can drive with a generator or other 15 amp 110 source.

The batteries are Fullriver DC310-6 gel-packs which are supposed to deal with hydrogen out-gassing. I think the model number translates to 6 volt, 310 Amp hours. They're connected in series to yield 48 volts DC to the inverter.

The system was sized to run the critical circuits in the house for 3 days. (Critical being the heating boiler (LP), some lights, the kitchen (except the electric oven), a sump pump, and a circuit for the living room and master bedroom.

The clash of ideas is the sound of freedom.