Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
DEAL: For $25 - Add A Second Phone Number To Your Smartphone for life! Use promo code SLASHDOT25. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. Check out the new SourceForge HTML5 Internet speed test! ×

Comment Re:But which kind of stroke? Too thin or too thick (Score 1) 41

This is why in the urgent situation, normal medical practice is if a stroke is suspected, the patient is transferred immediately to a CT scanner, as soon as a paramedic or doctor suspects the diagnosis. Ideally, the scan should be performed and the radiologist's opinion obtained within 30 minutes of the diagnosis being suspected. In the immediate situation, detection of significant quantities of blood can be made with near 100% sensitivity. With urgent MRI, results are even better with near 100% sensitivity for detection of ischaemic areas (regions with inadequate blood flow).

The problem is that if the stroke is old (i.e. a week or more), it can be very difficult or impossible to tell whether the stroke was due to bleeding or clot with a conventional CT. MRI, especially with modern ultra-sensitive blood detection techniques, can detect residual blood for years with near 100% sensitivity. At the same time, either CT or MRI angiography (blood vessel examination techniques) can look for evidence of arterial disease, which can be a clue as to the risk of a clot, even if the clot itself has dissolved by that point.

The fundamental difficulty, however, with delayed investigation, is that ischaemic strokes (due to clot) result in damage to the brain tissue and the blood vessels - so bleeding following an ischaemic stroke is very common. So, even if MRI does show blood a few weeks down the line, it is not always possible to tell, especially if a stroke is small, whether the bleeding was the cause or the effect. As it is small strokes which tend not to result in a blue-light ambulance trip to the ER, but instead an appointment with a GP or neurologist for some vague symptoms, this scenario is surprisingly common.

Comment Re:Yes, "line rental" is for POTS (Score 1) 82

Most cell phones have a built-in battery backup, which still works as long as the tower also has battery backup.

However, not all cell towers have battery or generator backup. If they do, it is rarely more than a few hours. For example, in the Lancaster floods in the UK in 2015, when the whole city lost power, there was an extremely limited service available for a few hours, but for the majority of the power outage, there was no cell service available within the city.

Comment Re:That's pretty smart (Score 1) 249

Apologies, as I had misunderstood your point of contention.

However, as far as the outsourcing goes, it goes further than I stated. It's common for the meter operator (more formally known as the meter asset manager) to outsource the actual owning of the meters; in that they will lease the meters from a "meter asset provider". You'll be pleased to know that the financial engineering in the UK power market is almost as advanced as the electrical engineering.

Comment Re:That's pretty smart (Score 1) 249

Yes. The grid operator provides balancing power, and they bid for balancing services from individual generators which is done in real-time and is based on frequency response and forecasts. However, the metering is delayed and is used to determine what services were actually provided.

However, there always has to be post hoc settlement. For example, if GenCoA has forward sold 100 MWh at 10:00-10:30 on 1/1/2017 to SupplierB - but GenCoA is unable to supply due to a technical fault - then GridCo will use balancing services to ensure that the power is supplied. MeterCo will in due course collect meter readings from SupplierB's customers and model what SupplierB's demand was during 10:00-10:30 on 1/1/2017.
Each electricity connection has a "profile" which is used to do this modelling - e.g. a private residence with electric heating has a different meter profile to a commerical premises with gas heating - and these profiles convert the annual total consumption into a series of half-hourly estimates. One complication is that it may take up to 2 years to collate definitive meter readings and submit final demand results - although there are several stages of provisional estimates prior to that point.

For example, SupplierB might only have demanded 90 MWh due to unseasonably warm temperatures - GenCoA might not have sold anything for technical reasons, and therefore there must be some sort of settlement process whereby the correct generator gets paid for the 90 MWh which was supplied.

It is a ridiculously complex system, but despite its complexity, it seems to work.

Comment Re:That's pretty smart (Score 3, Interesting) 249

You may doubt that there is an "extra metering" company, but that is exactly what happens in multiple countries with deregulated energy supply.

While I don't know in detail how the Dutch system works, the UK system seems to work in a similar way, and I describe that here:

An end user can choose their electricity supplier, who provides the retail service (i.e. billing, sourcing of bulk energy, customer service, etc.). The supplier sources the energy from generators via the wholesale market (ante hoc) and balancing market (post hoc). The electricity is delivered by a combination of the transmission operator, and the local distribution operator, who own and operate the transmission grid and distribution network respectively. Metering is provided by an independent metering operator.

The metering operator is responsible for collating meter readings and verifying the correct operation of the meters, as well as periodic recalibration. In the event that consumption data is unavailable or inaccurate, and the supplier and customer cannot agree on a reading (or if a customer is transferring to a new supplier, but the two suppliers disagree about the meter reading at changeover; it is, after all, common for customers to "adjust" readings when suppliers publish new tariffs or a customer changes to a cheaper supplier), the meter operator provides independent arbitration.

The independence of the meter operator is important, because the same meter readings that are used by the supplier to compute bills for customers, are the same readings that are used by the balancing market operators to reconcile bulk electricity accounts (including the post hoc accounting between generators and suppliers). Part of the job of the meter operator is to provide independent mathematical modelling of consumption patterns, to correct for incorrect or missing data, and which are legally binding on balancing market paticipants.

Another poster has mentioned an issue of energy theft elsewhere in the discussion, and the above system has an impact on the detection and prevention of energy theft. Because the same meter reading which the supplier uses to bill a customer, also determines the energy purchased by the supplier from the wholesale/balancing markets, there is little incentive for suppliers to investigate energy theft. If a meter reading is lower than it should be, then the supplier pays less to the generator. The discrepancy appears in the energy accounting of the distribution network operator, who must absorb the cost. However, if the energy theft is discovered, then the independent meter operator will compute a consumption measure which is legally binding on the supplier and customer. The supplier therefore has to pay for the stolen energy in the wholesale market. The customer, who is likely a deadbeat if they've been tampering with the meter, has no money with which to pay, and either disappears or goes bankrupt. Thus, having discovered an energy theft, the likely outcome for the supplier is that they take a loss equal to the value of the stolen energy.

Comment Re:radiation was detected (Score 3, Interesting) 139

Quite a lot less. 1 banana contains typically around 3-4 kBq of activity.

The activity detected in this study is 300 mBq/m3; so in terms of activity per unit mass, bananas are contain approximately 8 orders of magnitude more naturally occuring radioactivity than the pollution detected in the sea water.

While both K40 in bananas and Cs134 from nuclear fission are beta emitters, the energy per decay is lower in Cs134, so effective dose per decay is also lower.

Comment Re:Two Million Man-Years? (Score 1) 302

The simple answer is that there are a huge number of people who have been affected. Lots of land has been labelled "contaminated". A huge amount of industrial productivity has been lost. Housing and infrastructure has been abandoned and fallen into disrepair. People have lost jobs, all that will end up being compensated. Consider that close to 1 million people may have lost close to their entire net worth, and their health.

The most tragic part of that, is that the overwhelming majority of the evacuation and exclusion zone was inappropriate. Evacuation is known to be traumatic in terms of mental and physical health. In the case of the Fukushima accident, the evacuation was the direct cause of 60 deaths, and up to 5000 serious physical or mental injuries, even though contamination levels even in the most heavily contaminated regions would not have been expected to cause any acute radiation injuries or illness, and around 200 total excess cancer deaths over the next 60 years (had the region not been evacuated). http://users.physics.harvard.e...

Comment Re:Good ol' fun (Score 1) 302

It was sent to a distribution list, which to any reasonable person would be expected to have a very small distribution. The list was called "CroydonPractices", so presumably intended for the primary care practice managers in the Croydon region of London.

It is not at all clear who set up the distribution list, or whether it was the same person who sent the test e-mail. The issue was that this particular distribution list for some reason included all users.

I don't know what precautions the admin tools have to prevent mass replies. I think that some of the later versions of outlook will warn users sending e-mail to distribution lists if the number of recipients is greater than a certain number. However, according to wikipedia the backend for NHSmail is a customised version of outlook 2007, so it may be lacking some of the more modern features.

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.

Slashdot Top Deals

"'Tis true, 'tis pity, and pity 'tis 'tis true." -- Poloniouius, in Willie the Shake's _Hamlet, Prince of Darkness_

Working...