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Comment Re: No. Simply No. (Score 3, Informative) 522

Not that I am in love with Microsoft, but Excel has added quite a few "minor" functions since 2000 that dramatically increase usability.

For example, Excel 2007 introduced filtering and sorting by colors. And formats. Coupled with the existing conditional formatting, it significantly improved the ability of the software to sort based on any criteria, without using extra columns.

Going back a bit further, a key feature introduced in Excel 2003 was the ability to import xml datasets, and to set up templates quite easily which automatically imported data from xml files into preset columns. This can be done using macros, sure, but it's a lot easier to use the built in functionality.

Comment Re: @ CGordy - Re:sure, no problem (Score 1) 245

Without disagreeing with you, the point I was trying to make was that SIS or safety systems are hard wired and so are not physically capable of being connected to the internet, but (at least on the plants I've worked on) DCS data is available remotely via the company VPN. It is always possible to do financial damage by entering incorrect DCS setpoints, but it shouldn't be possible to compromise the plant safety (in a perfect world, anyway).

Obviously, my experience is in refining and chemicals, not nuclear, so the way control rooms are managed is probably different. I also suspect there is a difference in terminology, as I wouldn't class someone without a four year degree an engineer, but that's another discussion entirely.

Comment Re:sure, no problem (Score 5, Informative) 245

There's a lot of misconceptions on slashdot about how these "critical infrastructure" plants actually run. I've spent a lot of time working in chemical plants, and these plants are heavily instrumented, with all parameters recorded. These are accessible in real time to the plant engineers, who typically don't sit in the control room, and often aren't in the same state (there's a very limited pool of people available who are "experts" at some of these processes, and when a serious problem occurs companies want the best person to look at the data ASAP).

The guys who sit in the control room are not engineers. They're plant operators, and their job is to keep the plant running as smoothly as possible, and escalate the issue to an engineer if there's a non-standard problem. Most plants these days are so heavily automated that for normal, stable operation only two operators are required on site per say $100 million of plant (as a guesstimate - more during the day when scheduled maintenance is occurring).

The engineers at these sites are actually classed as management. That's because they have ultimate responsibility for the plant when problems happen, although they don't control the day to day operation of the site. Most of an engineer's day on a chemical plant should be spent looking at whether the plant is configured optimally, and trying to troubleshoot longer term problems which require a more theoretical viewpoint. However, they do have to get out of bed at three in the morning if something's gone wrong. They also have to manage the operators, and have a promotion path to "real" management - refinery managers (for example) are usually engineers.

However, what the article totally missed is that these sites already have two layers of control system - the Distributed Control System (DCS), and the Safety Instrumented System (SIS). The wikipedia contains a lot more detail, but essentially these SIS's are hard wired systems that aren't programmable at all, so they are intrinsically resistant to an internet or software based attack. However, they're very expensive (every trip needs to be built as a dedicated circuit), so these systems are only used to ensure that the plant fails in a safe manner, not continued operation. Priority is given to safety of people in the vicinity over integrity of the plant equipment - these systems wouldn't typically be used a stop a pump or centrifuge (for example) from running too fast, unless that could cause some consequential (human) damage.

Finally, an analog system would be a big step backwards from a safety viewpoint because it wouldn't allow the plants to automatically shut down safely when a problem occurs. Plant shutdowns are typically a multiple step process, and in a refinery (for example), large quantities of high temperature, high pressure flammable gases need to be disposed of, which would simply not be possible to safely "program" in an analog environment. Before digital systems came along, plant trips were "all hands on deck" incidents, with operators frantically adjusting adjusting setpoints on dials to bring the plants down. Of course, the risk of operator error was high, so automated shutdowns were a big step forwards in plant safety.

Comment Re: Pseudoscience debunked? (Score 1) 374

I have the same qualifications. The B.Sc. means Bachelor of Science, and the B.E. is a separate degree, a Bachelor of Engineering. In my case, my science degree major was in pharmacology, whereas my engineering degree was in chemical engineering.

Out of curiosity, what sort of arrogance make you think that you know the GP's qualifications better than (s)he does? Just because certain qualifications might not be possible in the US system doesn't mean that they don't occur elsewhere.

Comment Re: How Tragic (Score 5, Informative) 422

Ammonium nitrate is initially produced as an aqueous solution, and the water is then boiled off using carefully designed heat exchangers. The problem is that the resulting pure AN liquid will freeze if the temperature drops below ~170C but it decomposes increasing rapidly once the temperature rises above 200C, lower if the pH is too high or sensitising agents such as chlorides (salt) or oils are present. Decomposition can result in detonation when the AN is confined, and it's a significant hazard concern when designing or operating an ammonium nitrate plant or even just a large storage facility.

Comment Re:Um, no. (Score 2) 382

That level of service is normal on long haul flights, even in business. I have to travel between Australia and Europe regularly, and the attendant always memorises my name, takes my order at the start of the flight and ensures that my drink is topped up until I say stop.

Flying with Qatar it's even possible to make the whole journey without seeing an economy class passenger.

Comment Re:Chairlift (Score 1) 566

Over 80% of Australia's population live on the east coast, where the direct flights to NZ leave from (citation). The GP might seems to be one of the ~4 million people who doesn't, in which case he has a choice of a direct flight to Melbourne or Canberra or two flights to NZ.

To give the non-Aussies here some background on the costs skiiers in Australia face: lift passes are about $85 / day / person (for a 7 day pass), mountain access fees are about $40 / car / day, and cheap non-lodge accommodation for 4 (in a single bedroom apartment) is about $3500. Add to that food costs of say $40 / person / day, transport to and from the mountain and equipment hire, and it's easy to see how a week skiing costs the GP and his family $10k for a week, especially if they prefer the kids in a separate room.

Skiing is a very posh sport in Australia, and so the prices for everything snow related reflect that.

Comment Re:What's the advantage over diesel? (Score 1) 721

Diesel has a higher energy density and is cheaper to produce on a total life cycle cost basis (it requires less treatment to get high quality diesel).

However, those costs include construction of the refinery. Once the units are built to crack the crude and achieve today's relatively high octane ratings, the CAPEX is spent and profit is maximized by selling as much product as possible. The balance between diesel and gasoline is determined during design of the refinery, by selection of catalysts and treatment technologies.

Until a few years ago, gasoline was expected to be the dominant fuel in passenger vehicles for the US. Therefore, billions of dollars have been invested in upgrading refineries to maximize gasoline production.

It will take years to modify the US refineries to significantly reweight their product mix towards diesel. Some minor changes can be achieved by modifying process parameters like reactor operating pressures and temperatures, but these have most likely already been done as the popularity of diesel passenger cars has increased.

Comment Re:Only 1 million over a lifetime? (Score 1) 433

A good engineer makes that in under 10 years.

The figure is relative to the overall salary they would get if they'd started working straight after finishing high school. That means that the difference reduces to about $50,000 per year, and the high school graduate has a 4-5 year head start (I'm not sure how long a engineering degree takes in the states).

Also, the short version of the article didn't state whether it is before tax income or after tax income. I know that income tax rates are lower in the US, but at higher income levels the higher tax brackets take a considerable portion of an individual's take-home pay.

Comment Re:US Thinks Saudi Oil Reserves May Be Overstated (Score 1) 385

Wouldn't it be in the best interest of the Saudi's to give the opposite impression (IE, tell everyone there's lower supply than there really is to hike up prices)?


OPEC sets a total production quota, with the goal of maximising production without depressing prices. The overall quota then gets divided up between the individual member states, based on the size of their reserves. This has led to a situation where it is advantageous for countries to overstate their reserves, as that allows them to increase production (and profits) without a corresponding decrease in the oil price.

As this has been going on for a few decades, we've now got to a point where it is impossible to say even approximately how large the reserves of the OPEC countries are.

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