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Comment Re:It was a terrible deal for Britain anyway (Score 1) 170

Wave and tidal, seem to have catastrophic problems with cost so far. So far, no one has managed to demonstrate a scalable wave device. Many consortia have developed wave devices of various designs, but prototypes have proven usatisfactory. They tend to be of small scale and complex, and prototypes have had serious reliability problems and require extensive maintenance, making them unscaleable.

Tidal projects have been examined on a variety of scales. A number of large scale projects such as a variety of designs of barrage across the Severn or Mersey estuaries have been assessed. The problem has been cost and environmental damage (and the cost of environmental mitigation, which can double or triple the cost of energy); estuaries hold extremely large biodiversity which can be quite sensitive to disturbance. Several Severn barrage projects have been proposed with a range of sizes between 300 and 8,600 MW, with expected energy costs (based on a 120 year asset life) of between £150-350/MWh. Mersey schemes have been costed in the region of £900-1200/MWh after environmental mitigation. There has also been some assessment of small scale tidal lagoon projects, where barriers are built around small coastal bays converting them to lagoons, rather than estuaries. Proponents have suggested that in optimal locations, they may be able to achieve a cost of around £170-200/MWh.

So far, wind seems to be by far the most successful modality. Additionally, offshore has been remarkably successful as experience has been gained, and the CFD subsidy method has satisfied investors. There are a number of more ambitious offshore wind projects in the planning stages, but the capital costs may be higher, as the water is deeper and seabed more difficult. Additionally, there are potential connection difficulties, a number of the new sites under consideration are sufficiently far offshore than an AC electrical connection is not feasible. The problem is that the capital costs of offshore HVDC is substantial, with estimated capital costs for the inverters alone (excluding cable) in the region of £1/W; this is a similar magnitude to the capital cost of the turbines themselves!

Comment Re:It was a terrible deal for Britain anyway (Score 1) 170

The key subsidy for the Hinkley Point C project is the contract for difference (CFD) which assures a stable level of revenue provided that the plant performs. The CFD, designed to provide an inflation linked "fixed" price for energy sold, is the exact same model as has been used for renewable generation in the UK for the last decade or so. The idea is that any "low carbon" energy source can utilise the same financial and legislative framework. (With some complications because "renewable" energy is exempt from state aid restrictions under EU law, whereas nuclear energy is not). The CFD is valued so as to provide an agreed level of earnings (after interest, tax, depreciation and amortization) which is typically around 10% per annum if the project were to be delivered as planned. This framework has proved highly successful for the deployment of wind, solar and biomass, as well as other projects which are classed as "low-carbon energy" such as development of district heating systems, combined heat-and-power schemes, etc.

The CFD provides, for a specified duration, a known revenue per unit production. The CFD is inflation linked, but is also linked to O&M costs and financial risks to capital costs, so factors such as a change in finance rates for debt, tax rates, as well as change in staffing, maintenance, waste disposal/decommissioning or fuel costs for whatever reason, would trigger a CFD revaluation.

While the CFD is designed to transfer macroeconomic risks to the government, it is designed to retain project risks with the project owner. The CFD has a fixed duration of operation, which will start at the scheduled date of plant commissioning. Late delivery of the project effectively shortens the duration of the CFD. There is also an option for the government to unilaterally withdraw from the CFD, in the event that the project delivery is very late (7 years).

However, having developed this framework, the UK government did agree to take on some of the project financial risk, by agreeing to underwrite loans given to EDF in relation to the project. This would protect investors from an EDF bankruptcy, although as a French state-owned company, an insolvency would seem somewhat unlikely, as I would expect the French government to step in.

That said, even the loan guarantees have a get-out clause. In the event that the plant under construction in France at Flamanville is not successfully commissioned by 2020, then the loan guarantees are void. There is a real risk that this clause may be triggered: Flamanville is in a precarious state; Areva, the plant vendor decided to bring fabrication of the reactor pressure vessel in house, instead of subcontracting it out. Whereas the external contractor (Japan Steel Works) had already produced a good quality RPV for a Finnish plant, Areva had experienced delays in upgrading their forge to do the work, and had not validated their forging process by destructive testing of a prototype prior to fabricating the RPV. Only after the RPV had been installed, and the rest of the plant built around it, was a prototype destructively tested, and found not to be of acceptable quality.

Comment Re:I'm not a car guy (Score 2) 215

I don't know what the current auto security tech is, but proper PKI was shunned for a long time. Possibly for reasons of key battery life, or silicon IP costs.

I wouldn't be surprised if current systems are using techniques like HMAC, where both the car and the key use a pre-shared key. In this case, the factory keeps a copy of the database matching VINs to private keys. This allows a dealer or authorized locksmith to either order a new pre-programmed key from the factory, or possibly request the key for field programming a new key. Of course, if that database gets compromised....

If a proper PKI system was used, then it would be possible to program the car to a new fob, by having the fob transmit its public key to the car, and having the car add it to the authorization database.

Comment Re:Most "automation" isn't, just like this. (Score 1) 326

Agreed. "Organization" and "Prioritization" are two things, that my experience with EHRs has taught me, are two things that they just cannot do to any meaningful extent.

I recall the pain when we tried to migrate our data on an imaging system (PACS) which has a robust, fully standardized protocol for data exchange. With EHRs, things are much more complex, because most packages on the market use proprietary data formats, and while they can export or message across standard interfaces (e.g. HL7) there will often be loss of data, or a change in data presentation (a common one is loss of text formatting or loss of images embedded in text - e.g. rich text storage is quite common, but the data communication/migration interfaces may not support anything beyond straight ASCII text)

Even with our PACS migration, there was a problem, because annotations to the images were stored in a proprietary format, and were not preserved when the data was exported. "Oh. You want the image annotations? OK. We estimate that will take 5 days and 2 developers for development, testing and deployment of the script @ $5k per day per developer".

Things got better from there. "So, how are you going to get the data off the hard drives? The data is held in a proprietary format, and under the terms of the software licence, you will not be permitted to use or develop any software which uses this format once your licence expires. You are reminded that reverse engineering of the file format is strictly prohibited. We can provide a chargeable service for you. We estimate this will take 12 days of development and consultancy @ $5k per day. We will procure (at your expense) a suitable SAN and windows server. We will deploy a script which will convert our files into an industry standard form, and copy them to the new SAN. Please note that this will be performed at our facility. We will require you to ship the servers and SANs containing your data to our workshop at least 12 working days before your software licence expires. Once the transfer is complete, the new servers will be shipped back to your premises."

In the end, we found a specialist consulting firm that was able to extract the data (sans annotations) over the standard interface (by taking over the IP address and credentials of one of the CT scanners which was not used overnight) and trickling the data out overnight at rate not fast enough to trip the "intrusion detection system" (more like bulk data copy detection system) on the servers.

I can still recall the account manager's face when I told him that we would not be needing his $200k data migration service.

Comment Re:All missing the point (Score 1) 269

The issue is WHY is there price gouging. Is it because companies are deliberately charging 10,000% more than the normal market rate for no reason other than the desire to profit from a crisis? Or is it because the market has changed, and the only way these companies can remain viable is to charge 10,000% of typical market value for 1% of the time?

The problem is that conventional electricity generation plant is capital intensive and it has significant fixed (staffing and maintenance) and variable running (fuel and maintenance) costs. Because of the variable costs, these plants are sensitive to market pricing, which itself is sensitive to demand. Because of the fixed costs and cost of capital, the pricing power of these plants is dependent upon the number of hours on which they run. A plant which runs 90% of the time amortises its fixed costs over more energy, and hence requires a lower market price to remain viable.

One of the issues in the Australian market (and other markets) is that renewable generation is given privileged access to the electricity market. Renewable generators are protected by price support and guaranteed demand rules, which ensure that these generators receive a minimum price, even if the market price is lower, and energy purchasers must purchase all renewable energy before they are permitted to purchase any conventional energy.

Because renewable energy is variable, this changes the pricing dynamics. For much of the time, market pricing is depressed, undercutting conventional energy generators. As a result, these energy producers must amortise their fixed costs over a lower number of generating hours. In many cases, the operating hours are so few, that plants may be placed into deep storage, and destaffed. The problem now is how do you reactivate these plants in an emergency? How long does it take to get enough staff to bring the plant back into operational condition? Where do you find sufficient skilled contractors at 48 hours notice, and how much do these staff cost? How many hours do you expect to operate under emergency conditions, and what price do you need to charge to pay your contractors who are billing at emergency rates?

The failure in the Australian market is a failure of government. The government sets the market rules, and those rules are that power generators can only charge for energy sold. A potential solution, and one which has been adopted by other countries, is to split pricing into a per unit energy charge, and a per hour availability charge - both of which are auctioned separately. In such a scenario, the transmission operator bids for availability, and these fees ensure that power plants remain staffed, maintained and in a responsive state. The energy charges are charged as they are now. Advisers to the Aus government specifically advised this policy to avoid the current problem of conventional plants being decommissioned. They didn't listen. The plants have now been decommissioned or mothballed and are now not available to respond to a power emergency.

Comment Re:'Display tech guru' ... um okay. (Score 1) 90

Helium has a very low latent heat of vaporization. As a result, an uncompensated heat flux of 1 W into the cryostat will boil off about 15 litres of helium per hour.

With most MRI magnets only holding a spare inventory of under 300 litres, there would be a significant risk of quench if power could not be restored within 24 hours or so.

For this reason, backup generator power for the chillers is strongly recommended for MRI systems, even if generator power is not provisioned for the operation of the scanner itself (up to 150kW for the RF and gradient amplifiers, with extremely rapid load rise times and as these are precision electronic systems, the generator needs to be able to maintain adequate voltage regulation under this very difficult load). This is the case at my hospital. We have 4 MRI scanners, but we only sufficient generator provision for the chillers, and not for the scanners themselves.

Comment Re:'Display tech guru' ... um okay. (Score 4, Informative) 90

EM shielding is still essential, and nothing has really developed to change this. The signals are incredibly weak, and extensive RF shielding is required. To give an example, an incandescent light bulb in the scanner room which is reaching end-of-life can produce so much RF from micro-arcs on the failing filament that it can completely swamp the signal.

Capital cost is still very high, typically in the region of $1.5 million for a 1.5T machine, and $2.5-3 million for a 3T machine. Capital costs for the more capable machines are going up due to various developments - e.g. parallel receiver channels (up to 256 channels in the latest machines), parallel transmit channels with higher pulse powers (currently 2x 40 kW RF power amps and transmit antennas, but systems with 4 or 8 transmit channels are in development). Not to mention that there is a push towards larger dimension magnets, which substantially increase the capital cost.

There has also been considerable development in new algorithms for faster imaging, by using incomplete or overlapped imaging acquisitions, which requires extremely complex mathematical processing. CT scanners went through this development a few years ago to improve quality and reduce radiation dose, and image reconstruction went from a 1 ms task running in software, to a 250 ms task running on a 20U rack packed with $250k+ of GPUs. It is likely that the next generation of MRI scanners will use similar compute hardware.

All MRI scanners made in the last 5 years are zero-helium loss, so should not require any top-up of helium. However, they do need heavy chillers to recondense the helium - chillers with cooling powers of up to 1 W are now routinely used, which bring with them energy costs of around $20-30k per year. Many manufacturers also offer helium-free magnets (essentially the magnet coils are bonded to a giant copper/aluminium thermal mass, which is bonded to a cryochiller), these are substantially more expensive in capital cost, and energy cost, and much less tolerant to power failure. However, for areas where helium fills are impractical or too expensive, then these are a viable option.

Comment Re:Windows 10 update will kill human beings (Score 1) 266

The defective application in this example is a electronic records system. It allows the doctors/nurses/technicians to enter medical data during a procedure, collects X-ray image metadata from the imaging equipment and combines with the doctors notes for transmission to a medical records system, etc.

Comment Re:oh crap (Score 2) 500

The other issue is that Windows 7 and 8 would install updates if you shutdown/restarted when there were updates pending installation.

In windows 10, shutdowns are actually elided into hibernation. This means that if you turn your PC off at night or when you go out, with windows 10, you no longer get updates installed when you are not using the computer. Instead, the updates require you to actively initiate a reboot interactively - in other words, you can only install updates when you are actively using the computer.

Comment Re:Missed the point (Score 5, Informative) 155

Traditional refrigerants like R-12 (dichlorodifluoromethane) have massive ozone destruction capability, 1st generation replacements like R-134a (1,1,1,2-tetrafluorethane) has minimal ozone destruction capability but very high global warming potential (thousands of times more potent than CO2, gram for gram), 2nd generation replacements like R-1234yf (2,3,3,3-tetrafluorpropene) while having no ozone destruction capability and minimal global warming potential suffer from being highly flammable, increasing the risk of leaks.

The advantage of CO2 is that it is neither flammable, ozone damaging, high GWP, nor significantly toxicity. The disadvantage is that substantial re-designs of refrigeration systems are required to use it, as well as some changes to operation/maintenance.

The transition from R-12 to R-134a, is near drop-in, with only minimal redesign required for optimal performance. To switch to R-1234yf, the re-design required is relatively modest (pressures are higher, so a different pump is needed), but otherwise the principles and basic system architecture are the same. With CO2, you are dealing with transcritical fluids, and this requires a significant architectural change to the refrigerant circuit (as there is no condensation of the refrigerant, so no liquid refrigerant in the circuit).

Comment Re:Fun thing about TRIM (Score 1) 460

The standard is that a TRIMmed LBA should read as all zeros. This is so as to permit the use of TRIM in RAID arrays while preserving parity consistency.

If the OS needs to TRIM an entire RAID stripe, it fires off a TRIM command to the data drives, and calculates parity for null data, and writes that to the parity drive.

Comment Re:Wrong title (Score 2) 218

Even this interpretation is misleading. What actually occurred was that total renewable electrical energy generated in Scotland exceeded half of electrical energy consumed.

Scotland does not have indigenous demand sufficient to consume its electricity generation; about 35% of its electricity generation is exported to England. About 2% of electricity demand is imported from England during periods of low wind generation.

Comment Re:So much slower than 100GBase-RZ...? (Score 1) 57

100GBase-ZR achieves its 120 Gbps line rate by using a complex modulation scheme to encode 3 bits per symbol. 2 bits are transmitted using QPSK and 1 bit is transmitted by choosing either horizontal or vertical polarization.

The issue with long-haul transmission is that you only have a limited bandwidth available which works with optical amplifiers and avoids the water "dip". It's common to use DWDM techniques to cram multiple individual streams onto a single fiber. This yields just under 100 usable channels of 50 GHz bandwidth. The advantage of Juniper's proprietary "100GBase-ZR" protocol is that it needs only just over 40 GHz of bandwidth, so fits into a single channel.

The technology described in the article is about a new type of VCSEL laser diode. These have been widely used as transmission elements, but have traditionally had limited on-off bandwidth, hence early 10 Gbps transceivers often used much more expensive lasers such as Fabry-Perot lasers, and devices operating on 25 Gbps lanes have resorted to the even more expensive Mach-Zender optical modulators. VCSELs are easy to fabricate and cheap, hence if a simple On-Off modulation is sufficient then they are ideal (not to mention that carrier-switched modulation is easy to demodulate, unlike the nightmare which is DP-QPSK). The disdvantage with OOK is that the bandwidth equals the symbol rate, so 50 Gbps OOK would not fit into a single 50 GHz channel with guard bands, and would require a larger channel allocation on a trunk fiber.

Comment Re:Go nuclear: Free software download (Score 4, Informative) 193

But that wouldn't really achieve much. The main feature of Slysoft's solution, was not the software itself (which is certainly impressive) but the fact that they would update the software with new encryption keys every few weeks, often within days of a new encryption key being used.

AACS has a huge inventory of keys which can be used. Slysoft had managed to find an exploit in either a hardware or software player, which allowed them to extract the key when a newly released disc requested a previously unknown key ID.

Comment Re: It really is about security, not repair (Score 1) 381

Considering that the whole purpose of touch ID on the affected devices is to enable "apple pay", and apple pay works by storing a private key with authority to authorize payments from your bank account into the secure enclave. To make a payment, you re-verify fingerprint, which authorizes the secure enclave to sign a transaction message.

Because the finger print sensor is intended to communicate with the secure enclave, it is a potential avenue for attack; replay attack, fuzzing attacks on the secure enclave software, power/time cryptanalytic attacks, etc. Given the high value of the keys stored in the secure enclave, the latest version of the OS software is designed to fail even to boot if it detects a failure of pairing.

Earlier versions of the OS software would run with a mis-paired sensor, but apple pay would fail to work. The latest software update recognises that hardware attacks on the secure enclave might be possible, and pro-actively locks down the entire device if it detects a potential tamper attempt.

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