* Posts by Martin Gregorie

689 posts • joined 10 Apr 2007

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Emissions cheating detection shines light on black box code

Martin Gregorie

You haven't being attention. CO2 is not the problem for diesels; NOx is.

Now that's out of the way, it seems to me that there's a reasonably simple way to catch both types of cheating.

1) Borrow a car from a dealer chosen at random. Stuff a gas analyser up its tail pipe and drive it at least 62 miles/100 km. with the analyser logging its readings along with gradient and speed

2) put that car and at least one more through the statutory rolling road test cycle.

Now look at the results. Examination of (1) should spot the Chrysler-Fiat style of cheat: if there's a step change after the test cycle length you've got them. Comparing the two traces should spot ECUs using the VW type of cheat because the road test will show higher emission levels at all stages of the drive than the rolling road test does. This approach may well pick up hybrids of the two as well as new and unforeseen ways of cheating.

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Why Uber threw top engineer Levandowski under self-driving bus

Martin Gregorie

Re: fsck Uber

If by "they" you mean the owners of Uber and their money grubbing pals, then you're wrong.

"They" know exactly what they're doing - conning suckers into believing the 'gig' economy, zero hours contracts etc. are smart, 22nd century ways of making a good living, when in reality they're a way to make their hapless employees pick up the tab for medical, pension, holiday and other work-related expenses while "they" can trouser all that lovely money.

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Police anti-ransomware warning is hotlinked to 'ransomware.pdf'

Martin Gregorie

Re: Mmmm

..and make sure that mail preview windows are DISABLED - because they open attachments automatically.

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Britain shouldn't turn its back on EU drone regs, warns aerospace boffin

Martin Gregorie

No. You need an observer who is watching it with unaided eyesight standing with you. This has a lot to do with the very restricted field of view of most/all First Person View camera systems.

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Flying robots are great... until they meet flying humans, anyway

Martin Gregorie

Re: Also, what about emergency aircraft?

Currently no drones are permitted to operate further from their operator, or the observer if the pilot is using FPV equipment, than he can see to control it without visual aids or to exceed 400ft AGL. This is no different from any model aircraft and will always be the case. In this situation, normal VFR rules apply: also known as 'keeping a porper lookout" and/or "see and be seen".

This also keeps drones away from piloted aircraft since none of us are below 400 ft except when landing or taking off (ridge running by gliders and HGs excepted).

For drones to go further afield they'll need to carry some sort of aerial traffic avoidance system as well as a reliable method of avoiding collision with people, ground vehicles, cables, houses, trees etc. Something like FLARM would appear to be ideal for avoiding drone-drone collisions but AFAICT there's nothing yet on the horizon for dealing with the other collision risks I mentioned.

FLARM systems are currently carried by most gliders in the UK and Europe. They also being used by increasing numbers of GA aircraft and helicopters. FLARM systems are small, light and relatively cheap: if the HG people don't use them yet, they should probably think about doing so too.

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Do we need Windows patch legislation?

Martin Gregorie

RE: Do we need Windows patch legislation?

In comparing Linux with Windows, there's one thing you've fotrgotten: the Linux API is far more stable than the Windows API has ever been. This is clearly a matter of design philosophy: Linux has always valued having a stable, well-designed API, so that applications will continue to run despite upgrades while MS has clearly regarded using an incompatible API in each new Windows version as a marketing tool.

I'm running C code that I last compiled in 2005 and that 'just ran' until last March despite both hardware replacements and the six monthly cycle of Fedora upgrades. In March I moved from 32bit PAE kernels to X86-64 kernels and this did require my C code to be recompiled, but that was only to be expected.

If I was buying high-value kit such as an MRI scanner, mass spectrograph or radio telescope I'd require the control software on this kit to show the same level of OS upgrade resilience that I've experienced over the last 10 years, i.e. the control software MUST have the same EOL as the hardware it controls regardless of OS upgrades, etc. I could also reasonably expect a copy of the source code to be provided under an NDA or at least to be put in escrow as protection against its vendor's failure.

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RF pulses from dust collisions could be killing satellites

Martin Gregorie

See also a recent news item from the Cassini project about why and how they use a high frequency radio receiver to detect and measure microparticular impacts during Saturnian ring plane crossings.

Sorry: no URL. I heard the report on BBC Radio 4 this morning.

6
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You only need 60 bytes to hose Linux's rpcbind

Martin Gregorie

Re: Anyone actually use that ...

rpcbind is disabled by default for Fedora 25, but running "rpcinfo -s" locally or "rpcinfo -s hostname" remotely both start it. So, remember to run "sudo systemctl stop rpcbind" to stop it again if you don't need it running.

However, you'll find that running "sudo systemctl stop rpcbind" outputs this: "Warning: Stopping rpcbind.service, but it can still be activated by: rpcbind.socket" so it follows that stopping rpcbind may not do all that much good. I've just found out that running nmap from another host on your LAN can start it, i.e. any process that tries to open port 111 for any reason has the side effect of starting rpcbind if its not already running.

If, like me, your router doesn't accept any inbound connections then you should be safe, though you may still want to block port 111 on your hosts' firewalls.

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Alaska dentist 'pulled out patient's tooth while riding a hoverboard'

Martin Gregorie

Re: One more thing...

And finally, the most heinous of crimes that a dentist can commit with their clothes on; having the latest editions of pristine magazines in the waiting room!

...FTFY

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US military makes first drop of Mother-of-All-Bombs on Daesh-bags

Martin Gregorie

Re: Gather Dust?

Theres one huge difference between the MOAB and bunker busters like Tallboy, Grand Slam or the GBU-28:

- the MOAB has a thin alloy skin so it doesn't interfere with the blast wave. This means that it must be exploded above ground - drop it onto anything hard and it will splatter rather than penetrate.

- Tallboy is the archetypical bunker buster, or penetrating bomb. It weighed 5,400kg, but only 2,400kg, or just over 50%, of that was Torpex explosive. Most of the rest was a thick high tensile steel case, strong enough to be dropped through the few metres of reinforced concrete forming the roof of a U-boat or E-boat pen. Its tail boom and fins were light alloy and were only there to make sure it arrived nose first and spun up to stop it tumbling. One is known to have penetrated 18m into a hill to explode in the railway tunnel underneath.

Grand Slam was a bigger, 10,000 kg version of Tallboy

The Americans have the GBU-28, a laser-guided, 2,268kg bunker buster

THOSE are what you need to destroy caves and tunnels, not airblast bombs: I wonder why they didn't use one or two GBU-28s on the tunnel complex. Earthquakes and wrecked tunnels not spectacular enough for Proper Shock & Awe?.

3
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Boeing-backed US upstart reckons it'll be building electric airliners

Martin Gregorie

Re: A long way to go to catch up with Siemens

Yep, so it can tow an LS8-neo, fitted with 15m wings by the look of it, to 3000m in 78 secs. That's great, and fast too, but as it has a max flight time of around 15 mins, how many gliders can it tow to, say, a more typical 800m before it needs a recharge and how long is that going to take?

In any case, assuming its recharged from the mains, by the time you take into account transmission losses, the proportion of the electricity generated by fossil fuel and the generator's thermal efficiency, just how much greener is it than fitting a plain old Lycoming flat six and burning avgas?

Don't get me wrong, its nice engineering but I have severe doubts about its practicality as a tow plane compared with, say, a Robin GR-300 fitted with normal towing equipment (4-blade 'climb' prop and silencer) or whether the electric drive is much quieter, given that much of the noise comes from the prop.

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Lenovo's 2017 X1 Carbon is a mixed bag

Martin Gregorie

Re: Intermittent Freezes

I recently picked up a nice T440 off eBay (has the 1600x900 screen, 8GB RAM and 500GB hard disk). My first action was to nuke Windows and install Fedora 25 with XFCE. This setup is excellent - no unexpected pauses and about as fast as I'd hoped it would be, so I think your and Simon's long pauses are probably Windows-related. BTW, the SD card slot on this machine is full-size and full depth.

Parenthetically, I got the T440 to replace a ten year old R61i (CoreDuo, 1GB Ram upgraded to 3GB, 120GB hard disk, which was dieing) after I'd tried and failed to get it to accept a 500GB replacement HDD, but as the biggest disk it was designed for was 200GB and you can't now get new HDDs smaller than 320GB I thought it was stuffed. Then I had second thoughts, swapped in a 128BG Sandisk SSD and installed the same OS (Fedora 25 Workstation / XFCE).

So a comparison of the two is interesting. The R61i now boots somewhat faster than the T440, but the latter is quicker once its up, logged in and working on the task du jour. It think this is mainly down to the way Linux uses RAM. On the T440 I find that typically 7GB is used for caching and, as the entire contents of /usr are about that size, the difference in speed between HDD and SSD isn't noticeable during normal operation. OTOH, the R61i, which is running with an identical package set, only has 2GB of RAM available for caching, so will gain from the SSD speed during normal operation because it will be pulling a lot more stuff off the SSD than the T440 does off its HDD.

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US Customs sued for information about border phone searches

Martin Gregorie

Re: Do you have a mobile device?

There's a simple solution: get something non-smart. In my case its a Samsung B2100 - cost £55 IIRC, does everything I need a phone to do and is obviously far too dumb to interest Homes operatives. IMO this makes it the perfect phone to take to the US of A or any other place with an over-intrusive border garrison.

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Microsoft loves Linux so much, its OneDrive web app runs like a dog on Windows OS rivals

Martin Gregorie

What kind of linux user would actually ever want to use onedrive?

One who is sent a link to a OneDrive spreadsheet or WP document they need to read?

Here's an example from real life: one of my friends has recently gotten a new PC. As he and his wife are not even sligtly power users, the new box almost certainly runs Windows 10 and would seem to have come with OneDrive preinstalled instead of whatever all-in-one wp+spreadsheet package M$ used to include in consumer-grade Windows packages: I used to get bog-standard Excel XLS spreadsheet attachments from him. This time he just sent me a link to a OneDrive xlsx format spreadsheet, which I was able to download and save (using Fedora 25 running PaleMoon) and then to open it with LibreOffice 5.

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Martin Gregorie

Re: How many Onedrive users run Linux?

When somebody e-mails you a link to an Excel XLSX spreadsheet that turns out to be on Onedrive rather than attaching a spreadsheet file, you suddenly find out if it can be downloaded or not.

As it happened, the sheet was displayed and saved in my user directory with no trouble. I'm running Pale Moon on Fedora 25, so I was pleased when the speadsheet was downloaded reasonably fast, displayed correctly and saved as an XLSX file without issues, and even more pleased to find that oocalc (Libre Office 5) could read and save it as a proper non-proprietary spreadsheet format (.ods).

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This AI stuff is all talk! Bots invent their own language to natter away behind humans' backs

Martin Gregorie

Re: je ne comprend pas

"Stop it! You'll hurt your throat! - Frank Zappa

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Martin Gregorie

Frederik Pohl's "Slave Ship" shows how this can be done with just a simple yes|no signal stream, the example being how to direct a small dog to do something using only a clicker. Silence meant 'wrong choice' and a click meant 'correct choice'. Its an old book, but well worth reading.

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Europe will fine Twitter, Facebook, Google etc unless they rip up T&Cs

Martin Gregorie

Re: Good

Yes. About time the social networks and advertisers were reminded that the world doesn't owe them a free lunch and that "what's yours is not [automatically] mine" regardless of what their self-regarding T&Cs may say.

Offer a subscription model which guarantees that my personal data will not be resold and I'll take one out if I think the service offers value for money to me.

I'll even accept adverts provided they are static, don't obscure the content I'm paying for and are guaranteed not to contain or link to malware and the provider accepts liability for adverts or content that fails this last test.

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60 slow-mo A-bomb test videos explode onto YouTube

Martin Gregorie

Re: Mesmerising

If you want to kmow more of the background and technologies developed by the early atomic scientists, I can thoroughly recommend Rhchard Rhodes book "The Making Of The Atomic Bomb".

Its really a history of atomic physics from 1873 to 1945 and covers all the major personalities involved, what they did as well as the politics and the technology involved. It starts with the discovery of subatomic particles and ends just after the bombing of Japan, so if you want to know the background to Hiroshima, then this is the book to read.

His next book, "Dark Star", extends this coverage to the development of the hydrogen bomb and to other bomb projects and their participants: everybody has heard of the Mantattan Project and Russian efforts, but did you know that both the Germans and the Japanese were working on atomic bombs during WW2?

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Raw TRAPPIST-1 data lands tomorrow for crowdsourced hijinks

Martin Gregorie

More watery details

I'd really like to know more about the expected behavior of water on a tidally locked planet in the so-called Goldilocks zone. For instance, if the planet is in the outer half of the zone, is there really a sea or collection of lakes at the centre of the sunlit hemisphere, or has all the water been transported as vapour in the atmosphere to the dark side cold trap where it froze out and accumulated as ice?

If that happened, then you could find a bone-dry desert in the middle of the sun side, maybe a wet ring, possibly with some alien lifeforms, nearer the twilight zone round the edge of the sun side, and much of the water doing a Martian polar thing in the middle of the dark side.

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RadioShack bankruptcy savior to file for, you guessed it, bankruptcy

Martin Gregorie

Re: Solder Repellant

That matches my experience: generally shoddy merchandise, uninterested staff and unreasonably high prices. Shoddy, as in the sheet metal nibblers I bought that failed in less than 30 minutes of use and getting used to 10-20% of transistors being DOA. When I lived in Wiilsden, and later in Clapham, it was well worth a trip half across London to Edgeware Road and the electronic sales jungle there instead of walking 1-200 yds to the local Tandy.

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Did your in-flight entertainment widget suck? It's Panasonic's fault, claims software biz

Martin Gregorie

Re: Panasonic has blocked other third party products

I bought a Panasonic TZ-70 last September, along with a spare pair of Hahnel batteries for it. For most of its life its been running on a Hahnel battery, thanks to the disapearance of the second Hahnel and the original Panasonic en route to India[1]. I can't comment about chargers because the camera didn't come with one and AFAIK one isn't available as an optional accessory or I'd have bought it. Having to swap spare batteries into the camera to charge them is a pain: I'd much rather have an external charger.

[1] I think this happened during transit passenger bording checks in Dubai because that was the only place that the camera stuffsack was out of my site for long enough to anybody to find the stuffsack in my carry-on stuff, find the batteries and rifle through my spare SD cards, which were in an alloy SD card wallet. I know somebody had been through the camera stuff there because the SD cards (individually marked) were no longer in the same order different order that I put them in.

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RAF pilot awaits sentence for digicam-induced airliner dive

Martin Gregorie

Re: Airbus design flaw

There shouldn't be any flat surface on which to lay something in front of the control stick.

Have you flown a sidestick aircraft? What I hear from those who have is that a sidestick is quite twitchy because it moves less distance for the same rate of roll or pitch that a traditional control column or column or yoke does. As a result, its necessary to have your forearm on a flat surface in order to make small, precise control inputs.

I can't see how you'd design a forearm rest that you couldn't put a camera on, though I can see how it could be attached to the cockpit wall so it would not move with the seat. I personally wouldn't have a camera in my cockpit thats not secured to a mounting point or at least on a lanyard or neckstrap so it can't easily be dropped where it becomes unreachable and/or jam the controls, but ymmv.

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Who will banish spy-cam drones from US skies? The FAA doesn't want to do it. EPIC disagrees

Martin Gregorie

Re: It's the act, not the platform

Exactly. You don't expect the DVLA (Vehicle licensing authority in the USA) to prosecute car drivers for other misbehavior, such as shagging in their car or following somebody around and photographing them - that is for the police to prosecute if the driver is breaking a privacy or public behavior law.

Same goes for aircraft of all types: the CAA and FDA are responsible for licensing and aircraft safety issues, not for prosecuting other types of misbehavior. For example, in the UK if you fly an 8 kg drone within 50m of a spectator that would be a matter for the CAA because doing it breaks ANO rules, but using the same drone with a telephoto lens to photograph the same person inside his house from 100m away is a privacy issue that would be handled by the police, not the CAA, because at that distance you're outside the ANO limits for flying close to people or buildings.

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Dyson backs Britain plc with $2.5bn AI and robotics investment

Martin Gregorie

Errm, surely you mean...

But the EU's energy labelling regulations decree that voltage

I think you mean wattage. The voltage is set by the electricity generators and reduced by them when demand is high, so specifying it is meaningless for a mains powered device.

Also, as any fule kno, power = watts * time, so limiting the input wattage is also pretty futile because limiting it just makes the run time longer. The only realistic standard for, say, a vacuum cleaner would be to set a limit on the number of kilowatt hours used to clean a specified area of a standard floor covering. But try implementing that sort of standard for all mains powered domestic appliances and bureaucracy will think all its Xmases have come at once, so lets not go there.

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Cloudbleed: Big web brands 'leaked crypto keys, personal secrets' thanks to Cloudflare bug

Martin Gregorie

In any case...

... why should anybody be publishing malformed HTML? Haven't they heard of HTMLtidy?

This also applies to web authoring tool vendors, who should be using fully comprehensive, properly maintained regression test suites and making sure that the comparison outputs contain valid HTML.

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Ad men hope blocking has stalled as sites guilt users into switching off

Martin Gregorie

Re: As I said before...

The publisher outputs two ad streams: one for silent, static ads and no popups and the other is anything goes. Your ad blocker could be set to 'block', 'static ads only' or 'full-fat' for those who think ads are the best part of a website. The silent ad stream would be only for plain text, limited HTML, and PNG/JPG images that get a pass from a scanning program[1] *before* the ad publisher distributes them. Its up to the publisher to do that right: if they don't then switching the adblocker mode to 'block' will fix things.

[1] to filter out malware and URLs linked to malware - obviously - as well as ensuring that no disallowed file type or content gets into the silent, static stream ad stream.

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Martin Gregorie

Re: As I said before...

My ad-blockers stay on until the advertisment publishers are prepared to guarantee that they've filtered out malware from their ad streams AND carry liability for the malware they miss, but I'm not holding my breath for this to happen.

An additional nice-to-have would be an adblocker option to suppress any ads that aren't silent plain text or still images. I don't mind static ads, so would probably let those through provided they don't contain malware or URLs leading to malware: after all the content providers have to eat too, but ads that jiggle, flash or squark are never acceptable here.

I'd even subscribe to an ad-free version of the websites I visit regularly - and already do for sites like Avbrief.

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KCL external review blames whole IT team for mega-outage, leaves managers unshamed

Martin Gregorie

Agreed. Any copy of the data that isn't complete and held offline, either in a firesafe or (preferably) in a different building that's far enough away to survive destruction of the data center is not a DR backup.

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Blundering Boeing bod blabbed spreadsheet of 36,000 coworkers' personal details in email

Martin Gregorie

Re: Here we go again

...and you have to wonder exactly where 'an employee' works in the Boeing corporate structure.

Who would have access to that type of data outside of HR or the C-suite? But could one of them possibly be so careless? Shirley knot!

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BS Detection 101 becomes actual University subject

Martin Gregorie

Re: Hmm...

Of course. Other places you might think they'd be running degree courses in BS are NESTA, the various government-sponsored catapults and around Silicon roundabout. However, a moment's thought shows that teaching it in any of those places is massive overkill.

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Love lambda, love Microsoft's Graph Engine. But you fly alone

Martin Gregorie

From an ignorant, long-time DB designers's viewpoint...

The article's description of Graph DBs make them sound more or less like updated versions of IDMS, a B.F.Goodrich-developed mainframe DBMS that preceeded relational databases. In IDMS the 'edges' were represented by pointers linking the nodes and programs traversed the database by walking the pointer chains.

Is this a fair comparison?

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BlackBerry sued by hundreds of staffers 'fooled' into quitting

Martin Gregorie

Re: Read it...

I'd need to know How the papers were presented, and how much employees were allowed to scrutinise them before they signed and what was on offer if they didn't sign before I could pass judgement on the deal.

I don't think any of us can understand why they signed such a letter without knowing the circumstances in which they signed.

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Probe President Trump and his crappy Samsung Twitter-o-phone, demand angry congressfolk

Martin Gregorie

I can see this from four thousand miles away, why can't the people who actually live there?

Because they're too close to the problem to see its full humungousness.

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Want to come to the US? Be prepared to hand over your passwords if you're on Trump's hit list

Martin Gregorie

Re: Presumably

Different passwords for different services, 2FA etc? Mr Average Joe Public doesn't do that.

Yes, Mr Average Joe Public does, because there's at least one UK bank that doesn't use passwords for their online accounts: they use a 2FA device for all web-based access.

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Vivaldi and me: Just browsing? Nah, I'm sold

Martin Gregorie

Re: Still need more

Agreed: I don't like the single, zoomable text size control: its too imprecise. Being allowed to choose both font and point size, as used by Firefox and Opera, is preferable.

However, I'd be happy if Vivaldi never got the promised e-mail agent added to it. I have always preferred programs that do just one thing and do it well and have no problem with using a separate e-mail agent (such as Evolution) and newsreader (I use Pan).

However, this is all rather moot since the Vivaldi package has vanished from Fedora and I didn't like it well enough to have looked for more direct ways of installing it. Maybe dropping it as a supported package was a response to discovering the Chrome renderer's phone-home sneakiness? If so, hats off to Red Hat for giving it the chop.

FWIW, my browser of choice is currently Pale Moon. This is a Firefox clone that omits a lot of the recent bloatware and is subjectively faster.

7
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US tech giants take brave immigration stand that has nothing to do with profit whatsoever

Martin Gregorie

Re: That's a long article, let me condense it for you.

Not Trump this time: turn round and look at who's talking.

See them now?

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Korean boffins vow 1,000km-an-hour supertrain

Martin Gregorie

Re: Tubes are cheating

Viaducts, pah! I want to see it doing wall-of-death vertically banked turns at 1000kmh.

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AI shoves all in: DeepStack, Libratus poker bots battle Texas Hold 'em pros heads up

Martin Gregorie

Isn't the real test of an AI poker player...

How long will it take or how many games must it play to cover the cost of its hardware?

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My fortnight eating Blighty's own human fart-powder

Martin Gregorie

Beat me to it. Have an up-vote.

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Government calls for ideas on how to splash £400m on fibre

Martin Gregorie

Re: Digital minister Matt Hancock

Problem is, who writes the programs?

That's quite obvious: trainees doing homework assignments.

7
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2016 just got a tiny bit longer. Gee, thanks, time lords

Martin Gregorie

I don't see what the fuss is about

Leap seconds are not a big issue and should not be a problem for any system designer or developer who is paying attention to what they are doing.

The C tm struct, used when converting between UNIX time (seconds since 1/1/1970) and human readable time has defined the seconds field as containing a value in the range 0-61, this allowing for leap seconds, since at least 1996 so nobody can complain that this is a new issue that they don't or won't unserstand. Similarly NTP, the Internet Time Protocol, has always handled leap seconds.

Any OS worth the name will have its own implementation of UNIX's ntpd (the client interface for NTP) and should also provide time manipulation functions equivalent to the POSIX set as part of the supported language's standard libraries.

All this means that there should be no need for applications code to handle leap seconds. Ever.

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Europe trials air-traffic-control-over-IP-and-satellite

Martin Gregorie

@Bob Wheeler

I think you've got that about right.

Something else to think about: during IFR, and an aircraft in controlled airspace is always flying IFR regardless of the weather or time of day, the pilots eyes are, or should be, fully occupied with scanning the panel. In these circumstances surely its better to use voice communications: since that's hands-free (the Tx button is normally on the yoke almost under the pilot's thumb) and doesn't need the pilot to take his eyes off the panel.

Yes, I know that airliners have at least two pilots in the cockpit and that one flies while to other handles commmunications etc, but controlled airspace is also used by bizjets and other, smaller aircraft with a single pilot and they will need to be linked into this system as well. Given that, it would be nice to know how this proposed screen is going to be fitted into an already packed instrument panel, the size and weight of the new gear with its satellite antennae and what its going to cost to purchase, maintain and operate it.

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Facebook's internet drone crash-landed after wing 'deformed' in flight

Martin Gregorie

Re: Vne of 25 kts at landing approach height? Really?

The fix, as mentioned in the article, is to fit an airbrake so that instead of needing to command a node-down to regain the glideslope the airspeed can be reduced, which will bring it back on to the glideslope, without increasing the vertical descent rate or exceeding VA.

Thats a good description of how speedbrakes, as fitted to fast jets, work but isn't applicable to airbrakes as fitted to lower speed aircraft such as gliders. In this case 'airbrakes' is really a misnomer and the American term 'spoilers' is more accurate. Well-designed airbrakes have very little effect of the airspeed. Their main effect, when opened, is to reduce the wing's lift, thus increasing the sink speed. The airspeed may increase, stay the same or decrease as the brakes are opened dependent on the design of the aircraft.

Examples: opening the brakes on a ASK-21 increases sink rate while leaving the airspeed almost unchanged. Doing the same on a Grob G103 increases sink rate AND airspeed, while opening the enormous brakes on a Puchacz raises the sink rate while causing an immediate drop in airspeed. You quickly learn to ease the stick back while opening the brakes in a G103 and to push the nose down if you're flying a Puchacz. These are all well-respected two seat training gliders. I flew all three types while pre-solo and have flown them all solo since then. Single seaters tend to be better behaved in this respect: none of the types I've flown have showed much speed effect from using the airbrakes.

Bottom line: if Aquila had well designed, effective airbrakes, merely opening them further would have put it back on the glide path without affecting its airspeed or requiring an an attitude change.

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Martin Gregorie

Vne of 25 kts at landing approach height? Really?

If the Farcebook Drone's Vne[1] is that low then, redesign or not, there will be very few parts of the world that it can be reliably operated from if they expect it to follow any sort of servicing schedule.

[1] Vne is the never-exceed speed limit for any aircraft. Exceed that by more than 5% or so and structural damage is likely. 5% may not sound like a lot of leeway, but remember that aerodynamic forces obey a square law, i.e. double the flying speed and aerodynamic forces on the airframe are four times higher.

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Body cams too fragile for Canadian Mounties – so they won't be used

Martin Gregorie

Re: GoPro might have an in here, if only

e.g. early digital Cameras - all they had to do was put standard USB mass storage device driver in it, so photos could be retrieved by a drive letter . but no . They made it difficult beyond belief by knocking up the shittest software ever that had all fancy ideas about tags and libries, but ultimately made the most basic and essential task impossible - transfering a JPG from A to B.

@ V.Jeltz

Have you tried using a USB connection and your computer's file manager to grab photos off your camera? I have three digital cameras: Pentax K100, Pentax Optio WG1 and a Panasonic TZ 70. All connect to my computers via a USB cable and let me use the file manager to drag and drop photos from the camera to my hard drive. No stupid apps needed, not even to empty the SD cards in the Pentaxes (the TZ70 insists on emptying its own image store). Come to think of it, this has worked with every camera I've ever tried it on.

Alternatively, I just take the SD card out of the camera, put it in a card reader and use the file manager to move photos on and off it. I'm running Fedora Linux, but this should work with every OS whose file manager access a flash card in a reader.

BTW, I agree with your comments about GPS apps, but why not write your own app? I bet one that didn't broadcast your whereabouts while draining the battery would be an instant hit.

2
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Information on smart meters? Yep. They're great. That works, right? – UK.gov

Martin Gregorie

Re: Honest

Len, you've got that wrong, I'm afraid.

If there are no benefits to the user of a new product but installing and using it will result in a financial loss, then keeping quiet about this isn't being honest.

The correct terms are "being economical with the truth" or "hiding the facts".

Which one you choose depends on whether you want to be polite to the product's sponsor or to say what's really going on.

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India added 240m phones/year build capacity in just one year

Martin Gregorie

Currently India is well on the way to repeating the Chinese experience. I was in northern India recently: the air quality was not good and visibility was frequently poor throughout Rajasthan and across into Utttar Pradesh. The Indians blame diesel vehicles for the pollution, but I'm certain there's a little more helping things along. Certainly the generally calm conditions you get across the Thar Desert and the Gangetic Plain don't help.

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Passengers ride free on SF Muni subway after ransomware infects network, demands $73k

Martin Gregorie

Re: Sign of the times

I remember that story from the early 70s amidst rumours of fully automated airliners soon to fly without pilots.

However, autopilots were around and in regular use in aircraft before WW2. Many WW2 bombers had them: every bomber carrying a Norden bombsight had an autopilot that was linked to the bombsight during the run into the target: during the run in the bombsight managed the autopilot's inputs to fly the bomber to the precise bomb release point.

By 1945, even DC-3 (C-47) troop transports were all fitted with autopilots.

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'Data saturation' helped to crash the Schiaparelli Mars probe

Martin Gregorie

Yeah, didn't we see something similar with Ariane 5?

The problem with the Apollo 11 LM's onboard computer looks like a better match.

There, leaving a docking radar on overloaded the computer's interrupt handler when they got near the lunar surface, but fortunately there was an astronaut on board who was able to manually fly the landing.

Here, violent gyrations as the parachute opened seem to have overloaded the IMU and caused it to output garbage which upset the computer that managed the landing.

A faster IMU and improved garbage detection and rejection would both seem like a good idea.

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