Posts by cyberdemon 3496 publicly visible posts • joined 26 Jan 2010
El Reg could have provided a link for posterity.. There are a few clips from 2000 on the U-bend.. Paxman doesn't look terribly impressed.
"The idea is that your mobile phone will vibrate in your pocket, and Ananova will be there to give you exactly what you want.. (fnarr fnarr)"
I have heard that, and I am a little skeptical how a 69MW Wind Farm can jump start the grid when the UK's biggest power station (Drax, 2.6 GW) had issued a warning that they aren't sure if even they are big enough to do it. (or perhaps they are too big?) I'm not sure how it works to synchronise and connect only the generators and disconnect all of the loads, when all power and comms are down.
But nevertheless, I think they really need to organise a full scale test of the Black Start mechanism. Much better to have a little disruption in peacetime, than to wait until we really need it and all the neighbouring grids are down due to a solar flare or enemy action.
Another part of the grid that could be affected by geomagnetic storms, I reckon, are XLPE-insulated underground cables, whether DC or AC. Overground transmission lines have a spark gap at each insulator, which protects the insulator from overvoltage due to lightning strikes etc, and these are spaced every few hundred metres. Underground cables i think would see just as much magnetic induction(?), but there is nowhere for the energy to go, because they don't have regularly spaced spark gaps, and they could also more easily overheat because they are coated in plastic and buried in a tunnel. Perhaps one of our resident HV power systems engineers could comment here
> The Victorians also struggled with the effect of space weather in 1859 when a huge solar eruption caused a geomagnetic storm that interfered with railway signalling and telegraph lines.
That was the "Carrington Event" that you mention
Current UK railway signalling equipment is pretty old, but I don't think much of it dates back to Victorian times. Signals changing from red to green is pretty unlikely. Signals failing altogether, far, far more likely.
However I'm much more worried about the effect of a CME on the world's interconnected electricity grids. HVDC interconnectors could be quite vulnerable to massive common mode current, and they tend to trip offline very easily.
The UK grid operators are also quite worried (search for "blackstart") that without the hulking coal plants with their massive turbine inertia, and with HVDC links and renewables requiring an existing 50Hz grid to sync to before they can supply power, it will be difficult to restart the grid if it does go down completely.
Sounds like it is a supply-chain attack on some kind of Cloud CRM (which ought to be banned in itself), so it could be any charity, anywhere
This is exactly the reason I gave to the chugger (Charity Mugger, the annoying clipboard-people who stop you in public places) at my local train station. She was collecting for some charity and I said I'd love to donate to you, here's some cash. "No I can't take cash since Covid". Well do you have a contactless card machine then? "No, you need to put your details into this IPad". So much for the Covid excuse then..
I told her there is no way I am putting my details in, because I don't frankly know who she is really working for, and I don't want to be on some database of people who could be persuaded to give to charity. "Oh, we don't sell your details, we take privacy very seriously". Can you guarantee that your data won't be hacked and leaked all over the internet? Er..
I asked her so then why can't you take cash or contactless card payments then? It's obvious that the marketing CRM database is as valuable if not moreso than the donations she is collecting. She started to get annoyed and said well I obviously don't want to give to charity at all.. On the contrary, waving her a £20 note, please take my cash. Take it! She would not, and fortunately for me I had a train to catch which gave me an excuse to end the ridiculous conversation.
Are you David Cameron?
You didn't reckon on the price of B****t though, did you.
There is such a concept as a hybrid fusion-fission reactor. Fusion reactors can't produce a lot of heat on their own (the reaction happens surrounded by vacuum for a start..) But they are very good neutron sources, and it is trivially easy (unlike fission reactors) to turn them off.
Thus, a fusor can be used as a neutron source to activate sub-critical Uranium. Basically the fusion becomes an on/off switch for the fission reaction, and because it is low-enriched, there isn't so much of a weapons proliferation issue.
Fusion as an energy source on its own though, is likely to be a dead end. May I remind you that the only practical fusion reactor that we have, that big one up there, has approximately the same power density as a compost heap. It's just such a mind bogglingly enormous compost heap that it glows. That's why when we try to do fusion on earth, to get a useful power out if it, we need even higher pressures and temperatures than the sun
Funny how the world is playing out to the plot of Deus Ex
When there are only two main players in a major marketplace, and the vastly bigger of the two, owned by a company with almost infinitely-deep pockets, deliberately operates at a loss, isn't that called anticompetitive?
GitHub isn't so much a marketing tool for Microsoft as a data-mine.. I was flabbergasted that they were allowed to buy it.
Not to mention the godawful and privacy-invasive HP Cloud Print service
No, I do not want my Printer to be on the Internet of Things, thanks! What's the point of printing to a printer on the other side of the country / world? It's a printer for goodness sake, it spits out a physical piece of paper that requires physical presence to pick up..
If you happen to be not near your printer but need to print something for later.. Save the PDF and print over WiFi when you're near enough to pick it up, instead of handing all your private documents to HP!
& HP have got to be the worst printer manufacturer out there when it comes to crapware, planned-obsolescence and refill-prevention DRM chips
> My point remains. We do not currently have the technologies to feed 7 or 8 o 10 million people and fuel a modern civilization.
But we do! It was called Nuclear Power, but the green lobby killed it.
It is now prohibitively expensive because the more it spends on safety, the less the uninformed masses trust it.
Er, no.
Basically a toy helicopter rotor has no friction until it gets up to speed. It doesn't need to produce power at low speeds, so it is possible to use sensorless (back EMF) commutation.
Encoders allow a brushless motor to produce torque at low or zero speed.
Even a (brushless) toy car needs Hall sensors, because it cannot, without low-speed torque, spin the brushless motor to a speed where the back-EMF can be measured, because the wheel is in contact with the road.
An EV doesn't need a clutch, but it does need an electronic sensor (an encoder) instead.
While it's possible to maintain and replace a mechanical component after the manufacturer has gone bust, it's harder to maintain and replace an electronic component
> Isn't that the BMW i7 "range extender"
That's just a ~3kW 4-stroke petrol genset, similar to what you'd have for a building site, albeit integrated into the car. It takes up a lot of boot space and it's not powerful enough to run the car without the battery. A gas turbine generator could be 10 times as powerful in the same or smaller package, so it would make for a true series-hybrid powertrain
What you've basically just said is that Corn is an extremely inefficient extractor of CO2 from the atmosphere, and that all of the Biofuels industry are effectively burning food.
Your idea could work if we had an unlimited amount of land and fertile soil to grow crops on, but the fact that there are many people in the world going hungry, suggests that we do not.
Also, do your corn stalks not rot down and produce Methane / CO2? I doubt if it is all really sequestered
An EV traction drive is not an "ESC" like you would have on a toy helicopter.
It needs to work at high stall torque, even a hobby ESC can't do that without sensors. It needs to be powerful and efficient across a wide range of operating points, unlike a fan, vacuum cleaner or a HDD platter, and it needs to respond to rapidly changing loads.
Because even if you monitor every super-cell and have fuses between each cell in a super-cell, it is still possible for a li-ion cell to burst into flames spontaneously, at what should be a safe voltage and temperature. Microscopic dendrites can grow inside (when it is charged too quickly when nearly full, for example), they don't completely go away on discharge, and they grow bigger on the next charge. When they are too big they can internally short circuit the cell. And if its neighbours were already warm, the whole pack can go up.
> Are you sure all the sub battery components are all individuall monitored and they are not wired in parallel for less sensors ?
You need high voltage to get the power, you can't transfer hundreds of kilowatts at four volts because you'd need 100,000 Amps (more, because the heating losses go with the square of current), so the "wiring" (copper ingots) would weigh more than the car. The top speed of the motor is also limited by the voltage.
So EV batteries run at 800 Volts, that is the most common standard.
The way to get more volts out of a battery is to put cells in series. Not all of them, but groups of them, called supercells. An 800V battery has at least 200 of those (some have multiple strings in parallel, so 400 or 600 supercells), and yes, they are all individually monitored.
There are ~200 supercells per parallel string in an 800V pack as I said. But there are multiple sensors for each supercell, and if there are multiple strings, then multiply that again. We are splitting hairs between "hundreds" and "thousands" of sensors. Contactless encoders are still encoders.. But the fact remains that there are many more things to go wrong in an EV than in an ICE vehicle, which can be largely mechanical, and easy to maintain.
Yes just like the "negative emissions" from BECCS that Drax pretends exists.
In reality, they are chopping down forests to burn, destroying ecosystems and polluting the air with far worse emissions than the dirtiest of dirty brown coal, all the while collecting "green" subsidies from the UK Taxpayer!
Personally, I am waiting for a "series hybrid" with a decent-sized battery and a compact high-speed gas turbine generator. It could be lighter than a BEV yet not suffer the range anxiety. It would double as an off-grid generator for your house.
On the other hand, it would suffer the same reliability issues of an EV, with the extra issues of a high-speed gas turbine, so not surprising that it doesn't exist yet :)
No, having worked for a manufacturer of BMSs, I can tell you, each supercell (a bunch of cells in parallel, producing 2-4.2V collectively) is individually monitored, twice. You can't rely on string voltage to tell you if one cell is failing. Similar for temperature. This is why E-Scooters (which are not well-regulated, unlike automotive batteries) keep exploding, whereas EVs don't explode quite so often. The only thing that you can monitor at string-level is current.
As for encoders, some (less efficient) drivetrains use Hall sensors for low-speed commutation and back-EMF for high-speed, but the more efficient designs use synchronous commutation, i.e. they rely on an encoder. They can fall back to other methods of commutation in the 'limp mode' that I mentioned.
> if you make strings of individual cells you would lose the entire string. if a single cell goes out in a bank the rest of the bank still works and does not interrupt the string so you don't lose the string.
As I said, they use multiple strings, made of parallel groups (called supercells). But if a cell within a supercell fuses, then the capacity of the supercell is lowered, so you need to monitor the (super-)cell voltage to detect this, otherwise the lower-capacity supercell will reach a dangerous voltage before the whole string does.
Like most technologies, design focus has shifted towards performance and efficiency, at the expense of lifetime, with a whiff or forced obsolescence. There is no fundamental reason why a condensing boiler can't have a cast iron heat exchanger like your 25yo boiler probably has, but it would be more expensive, it would take longer to warm up (so can't be used as a combi boiler) and would be (slightly) less efficient than a heat exchanger made with the thinnest possible stainless steel to get it past its 3 year warranty.
After the 3 year design life, you need a new boiler. Bonus for the manufacturer. It's the lightbulb cartel all over again, but scaled up.
Rotary position encoders are probably the most sensitive piece of an EV. It lets the drive electronics know what angle the rotor is at, so that it can apply the correct field to produce maximum torque. Without it, the motor cannot produce much torque at all. If the motor-encoder coupling slips by one degree, or if the electrical shielding is sub-par, it would force the EV into an extremely low power limp mode, if not disable it entirely.
I would guess that encoder issues are probably the second most common EV drivetrain trouble, the first being battery problems. If one of thousands of temperature, current or voltage sensors in the battery is dodgy, it probably also would put the vehicle into limp mode. (Yes, thousands of single-point failure possibilities. That should make any reliability engineer shudder. An 800V battery needs 200 (parallel groups of) cells in series, the voltage and temperature of each needs to be individually monitored. If one goes above 4.2V or below 2V then it is a safety hazard. So voltage sensors are often doubled up for safety, and series cell strings are often doubled up for reliability)
No, it's only Trussonomics if you don't do anything else to balance the books.
They could increase other taxes, such as income. If people have slightly less money to spend (because of higher income tax) but stuff costs less by the same proportion, does that not reduce inflation? What am I missing here?
> Why do we need to import nurses?
Because to become a nurse in the UK, you need a degree. It's easier, cheaper and quicker to qualify as a nurse in other countries.
And since UK nurses and junior doctors are not paid enough to recoup the cost of that degree, not many people want to study nursing.
But fundamentally, if you expel foreign skilled workers, they are gone pretty quickly.. But you can't magic up domestic skilled workers to replace them. You need years to train them up, if you can even attract enough people into the trades. It drives up inflation because the existing domestic workers that there are will demand higher pay, doing less work overall only for those who can afford it. That's why plumbers/builders/electricians/mechanics are so expensive, and why healthcare staff are moving to private healthcare providers.
> Where does the gov then get the lost VAT revenue
Well, the idea would be that it would stimulate the economy, so in the long run they would get more VAT revenue from the increased growth.
But what they did instead was to cut inheritance tax - that does absolutely nothing to stimulate the economy, and it only benefits the rich, i.e. tory voters.
"Did no-one tell them what the calls and texts are made of?"
A lot of those walnut-brains in power seem to think that it is the SIM itself that does the inter-wibbling, when in fact it is just an identifier
Remember when MI5 were shocked to find hidden SIM cards inside diplomatic vehicles? I wonder what they'd make of the trend towards eSIMs..
MISRA says that any of its rules can be ignored with a statement to say that this rule has been ignored for whatever ${reason}. There is no such thing as formal MISRA compliance, because there are few people who can say if all [${reason}] are reasonable.
It's easy to make a MISRA-compliant RTOS, as long as you restrict it to a MISRA-ble set of features. For any extra features, you need to write a ${reason} to ignore their rules.
One: MS are trying to hit out at Zephyr, which is a very fast-growing in popularity RTOS run by the Linux Foundation with excellent open source governance..
Two: MS are stopping active development of ThreadX, they are hoping that someone will maintain it for free, and they will not be continuing with its safety certification
Both may be true, but if Two is true then anyone who paid for safety artifacts in the past is a bit shafted.
> NHS Fife is on the wrong end of a stern ticking off by Britain's data regulator after it made a howling privacy error that aided an as yet unknown person who had entered a hospital ward only to walk off with data on 14 patients.
Meanwhile Palantir walks in, takes data on 75 million patients, and the NHS pays them £400 odd million for the privilege!
