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Comment: Lazertag (Score 3, Interesting) 209 209

Back in the day friends were into doing Lazertag with the original retail guns and detectors and they came to me to see what I could do for them. I reverse-engineered a gun, scoped the output to the IR LED in the muzzle and discovered it was a simple short burst of 1kHz, nothing complicated for the target detectors to register.

By the time I had finished they had a couple of hand grenades (push a button, toss it at the Other Guys, three seconds later it fired a burst of 1kHz through a bunch of small IR LEDs peeking through holes of the plastic casing made from laundry detergent globes) and a "knife" (push the handle down against the Other Guy's body close to their target, another short burst of IR from LEDs in the handle shielded from the holder). The best item though was the "bomb on a stick", an omnidirectional radiator on a short pole, just push it round a corner and fire it off. That one emitted for as long as the switch was held down and it had a LOT of IR LEDs. One-shot room clearance FTW.

Comment: Re:Forgetting something? (Score 1) 316 316

Something went wrong with this Falcon 9 flight. Assuming little has changed in its design over previous flights then that something could have happened on any previous flight and SpaceX were just lucky it didn't happen on an earlier flight.

The goalpost-shifting criteria of "how many successful launches do you achieve before the first bad one happens" is not something the insurers will look on with equanimity. What they want to see is a long unbroken string of successful launches like, say, the Ariane V which had its last failure back in 2002 and which has launched sixty-four times since then with every mission an unqualified success (no OrbComm-style failure-to-achieve-correct-orbit in that sequence BTW).

As for the Japanese HII failure, a strap-on motor on an HII-A failed to separate after burnout and it was aborted by the range safety officer. It was flight number 6 of that design.

The larger HII-B has four successes for four attempts to its credit, all cargo flights to the ISS. Hmmm, just ran some numbers -- the four Japanese HII-B resupply missions have delivered 19.8 tonnes of supplies, spare parts etc. The six successful SpaceX CRS missions have delivered 9.7 tonnes of cargo in total, slightly less than half that amount.

Comment: Forgetting something? (Score 4, Informative) 316 316

Where's the Ariane Vega, or the Japanese H2 launchers or the PSLV in that list?

Vega - five launches, five successful.

H2 (A and B variants) - thirty-two launches, one failure.

PSLV - twenty-nine launches, one total failure (the first), one partial where the final stage underperformed but the payload satellite used its own propulsion system to get to the correct orbit.

That moves the Falcon 9 down the listings a bit, I think.

Comment: Re:Don't rule out sabotage (Score 5, Informative) 316 316

"The only alternatives to SpaceX are NASA's AtlasV and the Russian offerings. That's well known."

Well, apart from Arianespace (the Ariane V medium-lift and Vega small-capacity launcher), the Japanese H2-B launchers (one will fly a cargo resupply mission to the ISS in August), the low-cost Indian PSLVs, the Chinese Long March series of man-rated launchers etc. etc. That's well-known.

Saying that this launch failure has certainly put a crimp in SpaceX's plans to nuzzle up to the DoD/NSA funding teat.

Comment: Re:Obligatory reading (Score 1) 419 419

That's via ENEnews, the Chicken Littles of the science journalism world especially when it comes to nuclear power and the radiation releases from Fukushima. They never let statements by wild-eyed panic merchants or serial exaggerators go by without blasting it out on their website.

Comment: 4k is the new black (Score 1) 558 558

I've got a 4-core 955 AMD CPU running at 3.2GHz in a generic ASUS motherboard populated with 8GB of DDR3 RAM, a 120GB Sandisk SSD on SATA-3 for OS and programs with a 3TB spinning-rust Toshiba drive for data. The video card is a lowish-end AMD R250 with 1GB of video RAM, nothing special, chosen because it was the cheapest card I could find with DisplayPort.

Why DisplayPort? Because my mad money went on buying a 32" IPS 4k monitor, the Dell Ultrasharp UP3214Q and I needed DisplayPort to drive it at 60Hz. I have no peripheral vision left. It's the best computer upgrade I've ever spent money on, even better than fitting an SSD as a boot drive. My eyes aren't getting any younger after all.

My previous monitor, a 27" Dell IPS 2560x1440 display is running in portrait-mode as a sidekick off the same card with no hassles but I do most of my computing (video, graphics, photoediting, browsing) on the 4k monitor directly in front of me. If you're hesitating about going 4k, my advice is don't wait. The IPS panels like this Dell are more expensive than the smaller TN 4k displays but I really wanted the extended colour gamut and good off-axis viewing the TN displays lack.

Comment: Re:Ericson and Nokia? (Score 1) 86 86

There are the Asha model Nokia phones which are intended for the Indian market but there are also other cheap featurephones like the 105, 120 etc. which are sold here in the UK from Amazon and other sources either SIM-free or locked to carriers as PAYG. They are branded Nokia and, I presume, built by them.

The Lumia smartphones are being rebranded as MS devices with the Nokia name being deprecated although a lot of sales listings still refers to them as Nokia Lumia.

The rumours suggest Nokia want to get (back) into smartphones after the non-compete agreement with MS runs out in 2016. We'll see.

Comment: Re:Ericson and Nokia? (Score 1) 86 86

Nokia do make mobile phones. At the moment they don't make small tablet computers with a GSM/CDMA voice stage like the Lumias, Samsung Androids or iPhones. They're called featurephones. You'll find them for sale in out-of-the-way stores like Amazon with options like dual-SIM, basic social networking support and the like for twenty or thirty bucks, no contract.

Comment: Re:Yes. What about them? (Score 2) 169 169

That's... odd. Australia doesn't have any nuclear power reactors. It burns coal for a lot of its power requirements and exports a shitload more to other countries who do the same. Of course it doesn't take back all the CO2 emitted by the foreign power stations when they burn that coal...

A quick Giggle shows that Australia has sent spent fuel from at least one of its research reactors, HIFAR to France for reprocessing. The waste from that reprocessing operation would normally be returned to Australia after being vtirified.

HIFAR (it's shut down and now being decommissioned) was small with only 7kg of fuel compared to the hundred tonnes plus of fuel oxide in a typical power reactor of today. The problem seems to have been that initially HIFAR was fuelled with highly-enriched uranium which was a proliferation danger hence the desire to reprocess the spent fuel. Most research reactors of this type around the world (such as HIFAR's replacement, OPAL) have been now reconfigured to use low-enriched uranium which poses less of a proliferation threat and in such cases long-term storage on site of spent fuel is probably more appropriate and cheaper.

Comment: Re:Yes. What about them? (Score 4, Insightful) 169 169

France imports yellowcake (refined U3O8 uranium oxide powder) and turns it into fuel (enriched UO2 uranium oxide pellets), burns it and reprocesses its spent fuel to make more fresh fuel. The small amount of resulting waste is vitrified and is currently stored above ground until the time there's enough of it to be worth putting in an underground repository which will be built in France, not Australia.

Where you get the weird idea that the countries selling uranium are required to accept and dispose of other people's spent fuel I don't know. In some cases spent fuel from other countries has been recycled by nations with the capacity to do so -- the UK, for example has processed spent Magnox fuel from Japan, turning it into fresh fuel rods which were shipped back to Japan. The deal involved the resulting vitrified waste also being returned to Japan in separate shipments. Japan's last Magnox reactor was decommissioned a few years back and the shipments of spent fuel, recycled fuel and vitrified waste have now come to an end.

Russia's Rosatom is offering some countries like Jordan and Vietnam a turnkey nuclear power capability where they supply fresh fuel and take away the spent fuel at each refuelling meaning the host country does not need to build its own waste disposal and processing facility.

Comment: Re:Thorium (Score 1) 169 169

The RBMK-4 reactors were putatively dual-use in that they could be used to expose uranium to a neutron flux for short periods, a necessary step to produce high-purity Pu-239 without much Pu-240. The British Magnox reactors[1] could also be operated in this mode, as can the CANDU family. However by the time many of these reactors (and especially the second-generation RBMK-4s) had been brought online in the mid to late 70s the major nuclear powers such as the Soviet Union had already produced and stockpiled all the weapons-grade Pu they'd ever need as weapons control programs started massively reducing the numbers of deployable weapons any nation possessed. Indeed today's stockpiles of surplus Pu-239 are an expensive logistical headache for the owners as it's difficult to downblend such material to use in power reactors, unlike highly-enriched uranium U-235.

[1] It is thought by some historians that the US test-fired at least one nuclear device which used Pu created in a British Magnox reactor. The US made nearly all if not all of its own nuclear weapons Pu in specialised breeder reactors in places like Hanford. In Britain's case most of its weapons Pu was created at Windscale (now called Sellafield) in an air-cooled reactor which famously caught fire in 1957.

Comment: Re:Thorium (Score 2) 169 169

Some uranium (U-233, U-235) and plutonium (Pu-239, Pu-241) isotopes are fissile. Thorium is not fissile and cannot sustain a fission reaction by itself. Th-232 can be bred up into U-233 which is fissile in theoretical LFTRs and the like but at that point the reactor is fissioning uranium to produce energy and neutrons for breeding more useless thorium into uranium.

U-233 produced in thorium breeder reactors can be extracted and used to make nuclear weapons with some work, the uranium and plutonium in conventional power reactor fuel would take a lot more effort to weaponise which is why all nuclear weapons states have used specialised breeder reactors and mil-spec uranium enrichment lines to produce high-purity material for their nuclear weapons.

Comment: Re:Until the non-compete clause runs out (Score 2) 40 40

Nokia is making and selling cell phones at the moment. It can't build smartphones (i.e. small computer tablets with a radio stage that can transmit and receive voice calls directly over mobile phone networks via GSM or CDMA) but it's a major player in the featurephone and basic cellphone markets with a lot of decent offerings at bargain prices for those folks who don't need a Cray in their pocket.

Comment: Re:$100 billion for 150 miles? (Score 1) 189 189

The Nishi Seto expressway doesn't stop in Onomichi, it just dives off the mainland to Mukaishima and beyond via the bridges and doesn't bring much to Onomichi itself apart from bicycle rentals for tourists. Mihara just along the coast is a much more active ferry port with regular sailings to various islands, and that's why Mihara gets Hikari shinkansens whereas Onomichi only gets the stopping Kodama service. Mihara's shinkansen station is integrated with the local JR line station down by the docks, a short walk to the ferry port. I use the Mihara station to get to and from Hiroshima when I'm staying in Onomichi (as I will be again in a few weeks time).

The Onomichi ferries are still in operation. 100 yen to cross the Pacific, what a bargain!

The company you mentioned, was that the Hitachi-Zosen shipyard on Mukaijima next to the bridges? I've been told it used POW slave labour during WWII.

Comment: Re:$100 billion for 150 miles? (Score 1) 189 189

It's sort of self-fulfilling that the bigger cities like Osaka, Hiroshima etc. have shinkensen stations near their centres because all the trains stop there. Since they slow down a lot before they stop the tracks can curve more than out in the countryside where the top speeds are achieved and straight-line no-grade track is required.

That's not to say the shinkansens slow down to an Amtrak crawl entering the big cities. The shinkansen tracks have blast walls where they pass through built-up areas as they're still going at over 150km/h and they'd blow out windows and knock over small children from the shockwave otherwise.

Other shinkansen stations have a pass-through track between the platforms where the expresses like the Nozomi run while the slower Hikari and Kodamas wait to let them pass. Many of those stations are some distance from the city centres. It's kind of fun to see the expresses blast through the stations at speed...

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