When the stockpile dwindles and the price of helium goes up, I guarantee extraction will take place.
That's ignoring a large part of the issue, which is that the helium is being extracted. It's an impurity in natural gas that can almost always be ignored if you are interested in the natural gas.
Because the natural gas is in demand, it is being extracted. Because there isn't the necessary demand for helium at the moment, there's nobody prepared to pay to separate it from the natural gas and store it. Profit is maximized short term by throwing the helium away, even if the long term maximum benefit is achieved by saving it.
This is unlikely to significantly change in the foreseeable future. The helium price will go up once the US reserves are exhausted, but only to the point where sufficient helium to meet current demand is separated. The rest will still be lost to space.
Unless, and until, the demand for natural gas approximately meets the demand for helium (based on their respective ratios in the gas field) then there will always be one or other wasted if the person doing the extraction is attempting to maximize short term profit. If we had absolutely no use for natural gas but a demand for helium then we'd be throwing the natural gas away instead.
I think it's more a case of the bank aren't able to get the IP address of the person who actually set up the DD.
The charity are not allowed to release that information to the bank, even in the case of fraud. Maybe Clarkson has decided to take this hit and has not requested the money back and has not made a complaint to the police.
Therefore there's nothing that the bank can do. Only the police have the powers to request the information that would be needed to investigate this fraud from the charity.
Assuming you are in the UK, you write to Amex saying you are cancelling the DD mandate. You CC a copy to your bank.
If Amex ever take money again after that they you contact your bank under the DD guarantee and they must[1] immediately refund the money (you might have to argue a bit with the telephone droids) and then the bank can fight it out with Amex to get the money back.
The thing with direct debits that people don't understand it that they can only be cancelled by the recipient of the money. That sounds dodgy, except that, if you tell the recipient to cancel the mandate then they must cancel it, and, once you've told them to cancel it you've got the cover of the DD guarantee if they ignore your instructions. (Hence why I said CC your bank)
[1] legally, it's not always trivial in practice but always possible.
Just has to do with coding methodology. strcpy is insecure, strncpy is more so. strncpy(src, dst, sizeof(dst)) is more secure than strncpy(src, dst, size_of_dst). Those are easy to fix security bugs. Other security bugs are harder to find as you have to trace the myriad of states the app can be in during mem writes.
strcpy is NOT insecure. It can be used insecurely.
But congratulations, you've just turned what could have been a borderline ok strcpy(src, dst) (ought to have been criticized at code review as the names of the variables are confusing) bit of code into (probably) a crash and definitely a buffer overrun if sizeof dst is larger than sizeof src.
I have lost count of the number of bugs I've had to fix after someone changed a perfectly good strcpy into strncpy. A common mistake is:
and then you get a bug because only the first four characters of src appear in dst followed by garbage.
Of course, then it gets changed to strncpy(dst, src, strlen(src)); because the original programmer did know what they were doing and the buffer was big enough.
Eventually we get to the brilliant: strncpy(dst, src, strlen(src)+1);
Fantastic! What an improvement! And yes, it really does happen in what was once good production code because some idiot has heard that "strcpy is insecure".
Another one I've seen is:
dst = malloc(1000000); strcpy(dst, "MESSAGE");
gets changed to dst = malloc(1000000); strncpy(dst, "MESSAGE", 1000000);
Yup, instead of writing 8 bytes, we'll write one million bytes because strcpy is insecure, but we won't fix the missing check for NULL. (there's a fairly good argument for not checking the return from malloc in much production code - if malloc actually fails then you're already so far up shit creek without a paddle that it's probably impossible to recover gracefully anyway. Obviously different considerations will apply if you're controlling a nuclear power plant than if you're writing a game)
strncpy is NOT a replacement for strcpy with a length parameter. Unfortunately strncpy has a very bad name, it should be called something like meminit_from_str() as strncpy ALWAYS writes n bytes and doesn't always write a null terminator. (I've also had to fix bugs where someone has replaced a correct use of strncpy with a version that guarantees to write the null)
strncat is a possibly safer replacement for strcat. However, the length parameter is so tricky to get right that I've seen cases where someone originally wrote strcat safely, that got changed to strncat "because it's safer" and then a bit later another change was made that caused a crash because the original change to strncat got the length parameter wrong.
becomes /* We'll just fit as much of the translated error as possible into this buffer */ strncpy(error, get_translation("ERROR:", lang), sizeof error); strncat(error, translated_error_msg(e, lang), sizeof error - strlen(error));
of course, even more common is to miss the -6 or strlen(error) completely than to remember the extra -1 that is required on the length parameter.
(The man pages are IMO, confusing for strncat as they usually say something along the lines of "appends at most n characters")
But seriously -- how would one get in touch with you?
It's not me but Google is your friend. You can find some rather interesting threads. Including one where someone says that knowledge of differential geometry is necessary:
Quite frankly I'm at something of a loss to imagine what outside of research would actually have a use for differential geometry (maybe I wouldn't be suitable for a job:-) ). But maybe I should shorten my sig to 'God said "dF=0," and there was light' just in case;-)
Tim.
Re:please stop with the Ocean Uranium Crap
on
Google Goes Green
·
· Score: 4, Informative
OK - fine. How many parts per million of uranium is there in sea water, eh? Now, take the number of parts of Uranium you will need to run a reactor. Multiple those two numbers, and you will get the volume of water you will need to boil off to get the uranium you need for ONE reactor.
About 3 parts per billion
That's the first I've ever heard about anybody being crazy enough to try to boil off the water to extract the uranium.
If 2g-U/kg-adsorbent is submerged for 60 days at a time and used 6 times, the uranium cost is calculated to be 88,000 yen/kg-U, including the cost of adsorbent production, uranium collection, and uranium purification. When 6g-U/kg-adsorbent and 20 repetitions or more becomes possible, the uranium cost reduces to 15,000 yen. This price level is equivalent to that of the highest cost of the minable uranium. The lowest cost attainable now is 25,000 yen with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses. In this case, the initial investment to collect the uranium from seawater is 107.7 billion yen, which is 1/3 of the construction cost of a one million-kilowatt class nuclear power plant
So, of the order of $1bn to setup and then around 250$/kg to extract using current technology to extract enough uranium to run 6 nuclear power stations.
How is maglev better anyway? So you reduce your rolling friction to zero, what do you save? 1% of total operating power? You'd spend a lot more if your using electromagnets to keep the 'lev' action going...
Mainly it's the dynamic loading on the rails that is the problem with trains going faster and faster.
A maglev is like a hovercraft with the load spread out over the full length of the train. A tiny imperfection in the rail doesn't cause every passing carriage to hammer at it, reducing the need for rail inspection and maintenance.
IMO, the biggest advantage of maglev is that it automatically implies the advantages that the French were far sighted enough to acquire with LGV - that there are dedicated lines for the high speed trains with no sharing with slow traffic. I was on a 225 yesterday from Durham to London which was on time until the last 50 miles or so when we got stuck behind a slow train and we had to wait until it had pulled into Stevenage before we could get back up to speed. That added ten minutes to the journey in the last half hour or so.
Then, is it the customer's fault that his ISP is grossly overselling their capacity?
And if their customer wants to download web pages in seconds but doesn't want to download GB of porn/p2p whatever?
The problem ISPs are having is that they don't want to impose hard limits on how much their customers can download each month because (almost) everybody's usage varies from month to month. A customer (me) who might download 2Gb/month usually might then suddenly download 5Gb in a few hours (new Debian release)
I even try and push as much of my usage as possible into the early hours.
But what I can't fathom is the animal-like need for vengeance against the poor government employees who lost the data as the result of one of these accidents.
This is the UK. Typically, unless the employee is criminally negligent the liability would fall on the employer even if the employee had broken the employers rules - e.g. leaving the laptop unattended in a car.
The employer will be expected to take reasonable steps to prevent data loss as a result of carelessness of employees - typically this would mean that if employees need to take data home the employer would provide a laptop that had disk level encryption. (Its unlikely that the employees mistake would even be grounds for dismissal unless it was a repeated offence)
Obviously there are grey areas, but I would expect "just" putting the data in an encrypted zip archive and expecting the employee not to decrypt it and keep it decrypted on the laptop would not be a defence - which is why I suspect disk level encryption is going to be required.
I think Towcester at least goes back to the stone age although the name has changed over the millenia.
Then there are names like Featherstonehaugh-Cholmondeley = Fanshaw-Chumley (although I think the hyphenation is more a case of "Just think if a Featherstonehaugh married a Cholmondeley")
In addition, New Horizons spotted the infrared glow from at least 36 Io volcanoes, and measured lava temperatures up to 1,900 degrees Fahrenheit, similar to many terrestrial volcanoes.
We don't get that at all in the UK. I _think_ there is still a married couples allowance which, can be applied to either the husband or wifes income (or shared)
But all the other allowances are per person. So if the husband is earning 40k and the wife is earning nothing then no account can be taken of the wife's allowances. This means that a couple both earning 20k are better off than one person earning 40k and the other earning nothing. (There are things called family income tax credits that I don't know anything about that might - or might not - even this out)
We also have a tax called Capital Gains Tax. Basically anything you buy and then sell again is assessed for tax (shares and property are probably the most common). There is a 9k/year allowance and if your gains are below that then you don't need to declare them. I also think some things are excluded (cars for example - so you can't use the loss on changing your car every year to offset gains elsewhere)
Your main home (personal private residence) is exempt from CGT.
Even if you give something away you are still taxed as though it was sold at full market value (gifts to charity are free of CGT). However husband and wife are allowed to transfer stuff between themselves without triggering the CGT tax.
Very much like how I understand American taxes work, all this tends to benefit the well off. Most families are completely unable to take advantage of their CGT allowances. Even if you assume the stock market grows 10% p.a. You'd need 90k invested per person. (No CGT on pension funds but there's still a 10% dividend tax that cannot be claimed back)
But couples who do have significant assets can often move them to the lower taxed person and so take advantage of their tax band. So, a couple with one person with an income of 100K plus say another 100K in equities making a dividend of 4k/year can transfer the equities to the non-earner and then get that dividend free of tax. Then when they come to sell they can transfer some of the equities back in order to take advantage of both peoples 9k CGT allowance. But a couple with one earner earning 30k who can't really save significant amounts have absolutely no way to take advantage of the non-earners allowances.
After couple of kicks in the nuts no-one sounds rather positive. And unfortunately bad employer can ruin employee so that he won't be able to perform 100% for the next employer. Enough bad employers can bring anybody to a situation where one thinks about moving to a totally different area.
Just my personal view of the overall situation at the IT industry.
This might be true. But a first rate, confident, programmer in the IT industry who isn't on a super high salary in the City (earning well in excess of 100k) can just jump ship.
I've had to do it a few times.
1. I made a huge mistake going to work for one company (I probably partially overlooked the danger signs because they offered me a base salary 33% higher than I was getting). Within two weeks I realized I'd made a mistake going to work for them. Within six weeks I'd moved on and got another (smallish) salary increase. (I actually asked to be released from my four week notice period but the company asked me to do two of them to finish off what I'd been working on otherwise I'd have been gone in four weeks)
2. I was (unexpectedly - fallout from the.com crash) made redundant four weeks before Christmas (paid until Christmas Eve). I started a new job at a slightly higher salary on the first working day of January. Infact, for this job I actually demanded a second visit/interview (because I didn't want to make a similar disasterous mistake again - you can explain one six week job on your CV. Two or three starts looking very fishy) even though they were prepared to offer me a job after the first interview.
16.2% for 0 to 5,354 Euro 21.2% for 5,355 to 21,737 Euro 31.2% for 21,738 to 52,624 Euro 34.2% for 52,625 - 67,286 Euro 28% + 4,171 Euro for 67,287 - 109,787 Euro 33% + 4,171 Euro for 109,788 - 238,688 Euro 35% + 4,171 Euro for 238,689 Euro and the remainder above
In the UK it's approximately: 0% for 0 to 7000 EUR 10% for 7000 to 10000 EUR 22% for 10000 to 53000 EUR 40% above 53000 EUR
Additionally we have Employees National insurance 0% below 7000 EUR 11% for 7000 to 47000 EUR 1% above 47000 EUR
And employers National insurance (Which the employer pays but doesn't appear anywhere on your payslip) Which I think is 12.8% on everything.
(The employers NI doesn't affect your take home pay - if you earn 100000 before tax you will pay approx 28000 Tax, 5000 NI and take home approx 67000. Your employer will pay an additional 12800 NI so the overall income tax rate is either 33000/100000 = 33% or 45000/112000 = 40% depending on how you account for the employers NI)
Then there's VAT at 17.5% on almost everything.
Contributions to a pension scheme are paid gross (but employers NI is still paid)
Perks such as health insurance are taxed as though they were income but you don't pay any more NI.
House prices vary a lot. In London, average house prices vary from 1M GBP (1.4M EUR) in Kensington and Chelsea to as little as 200K GBP 280K EUR in Barking and Dagenham.
The problem comes about because the police don't have a clue.
Consider the scenario. You are arrested for a crime you didn't commit. Fortunately, despite the police trying to pin it on you, the real culprit confesses and you are released without a stain on your character.
Then a little while later you are arrested again because your fingerprints (which were only stored because you were incorrectly arrested before) are found on some recovered stolen mail. The only problem being that you were the _VICTIM_ of the theft. Yes! Your fingerprints were on the mail because you _POSTED_ it!
No attempt by the police to investigate. Finger print match. Call the person in to the station. Arrest them immediately. And then tell them to accept a caution to get it over with!
The debian etch 2.6 kernel will run on a 12Mb 486DX2-50 machine. What won't work is booting with the default initrd that apt-get install creates but if you strip that down it will boot fine.
much as a pint of water weighs a pound (the world around, and takes 1 BTU to raise temperature by 1 degree F).
You've got a strange definition of world there.
On this side of the pond: "A pint of water weighs a pound and a quarter"
I'm ashamed to have to say that it appears the majority of my countrymen would prefer to use "fundamental" units that have rhyming mnemonics rather than units that make all the calculations simple and consistent across the world.
Our scale is based on the twelth root of two. (Thus the octave, a factor of two, is broken up into twelve steps.) It's a convenience to let us have instruments that can play in many different keys without needing to be re-tuned.
No, this isn't right.
The modern piano is typically tuned with a stretched octave. The style and size of piano will determine the amount of stretch together with the type of room and type of music to be played to an extent. (In general, the larger the piano the less the stretch)
Tuning a piano well (ignoring the maintenance etc that a good piano tuner will also do) is very much a skill depending on an excellent ear and good musicality and not something that can be done with a frequency meter.
There is a very good reason top pianists take their piano and piano tuner with them when touring.
I was acting as an usher and general person helping out when Sviatoslav Richter performed in the Holywell Music Room after collecting his honourary doctorate at Oxford. The Steinway was moved out into a back room and his Yamaha installed. His tuner then tuned it up, he played a few little bits and then the tuner completely retuned it (tiny adjustments that I'm not sure I could actually hear). All to perform, IIRC, one Hayden piano sonata. (He then cancelled his concert in the QEH or Barbican - can't remember which - the following night because he was exhausted from all the excitement in Oxford:-) )
I later got a chance to play on his piano (after his death) at the Music Messe in Frankfurt. I'm certain that the only reason my playing didn't sound as good as his was I didn't have the piano tuner retune to match my style of playing and the room.;-)
G# and A#/B-flat are frequently wrong, and tend to be wrong in the same direction. They haven't proven orchestra-tuning is the case, it's just their hypothesis that the blurring around A is likely due to that factor.
Just as likely that these are the ones that are the most out of tune.
In a good orchestra, A# and B-flat and G# and A-flat won't even have the same pitch in the same piece even if the orchestra is tuned to A-440. (Obviously if they are playing a piano concerto then the orchestra will tend to play a bit more out of tune so they will converge)
The (perfect) octave, fourth and fifth are natural harmonics. So natural, infact, that if you silently hold down a G and then strike the C an octave and a half below the G will start to audibly resonate (even though on the piano the G is slightly out of tune compared to the C)
Twelve consecutive fifths (and I'm using consecutive here to mean going up a fifth, then another fifth etc rather than it's musical meaning) will (almost) bring you back to the original note but 7 octaves higher. Twelve consecutive fourths will (almost) bring you back to the original note but 5 octaves higher.
Other intervals also have rational ratios.
Major third = 5/4
And if you look at the harmonics of the fundamental:
1 - Fundamental 2 - Octave 3 - Fifth (3/2) 4 - Octave 5 - Major third (5/4)
And as an aside, the clarinet only has odd harmonics, therefore the upper register is an octave and a fifth above for the same fingering.
A bell has a resonance a minor third (6/5) below the fundamental.
(The minor third is the interval between the major third and the dominant: 3/2 / 5/4 = 6/5)
JS Bach was one of those who worked on a solution to this, and he came up with the modern even-tempered scale, which averages out the intervals so that all keys are equally in-tune (or out-of-tune).
Actually Bach came up with the well-tempered scale. The equally tempered scale is just a special case of the well-tempered scale (and I'm pretty sure Bach wouldn't have written his 48 if he'd really intended an equally tempered scale. He'd have written one major and one minor piece transposed into 12 keys each)
If it weren't for being well-tempered, anybody could tune a piano - infact it would be fairly simple to design a robot to do it but a good piano tuner will tune a piano to suit the room and the type of music being played and not rely on electronic tuning except maybe for the first note.
If you have a well-trained ear then you can hear the slight beating that indicates this slight out-of-tuneness when you strike an open fifth on an even-tempered instrument (such as a piano). String and wind players are of course able to make the slight adjustments to overcome this tuning compromise, and if you listen to a really good string quartet you can sometimes hear the difference.
And singers. My partner can sing a full cycle of descending fifths (jumping up an octave where necessary) and arrive at exactly the "wrong" note.
(for non-musicians, a perfect fifth has a frequency 3/2 and a perfect octave 2x the fundamental. A perfect fourth is 4/3. (Note a fourth plus a fifth = 4/3*3/2=2=a perfect octave) (she finds this easier to sing repeated descending fifths but we can pretend a descending fifth is an ascending fourth plus an octave jump)
Going up a fourth 12 times brings us back to the same note (5 octaves higher) but:
going up 12 fourths (4/3)^12 = 31.56929 while going up 5 octaves: 2^5=32.
So these are the same note arrived at via two different routes and going up in fourths the singer arrives back at the tonic about a quarter semitone flat as compared to the piano.
I've always wondered what people with perfect pitch do in this circumstance. I think one of the Beethoven piano sonatas has a complete cycle of fifths. Obviously, on the piano there are 12 tiny errors that mean at the end we're on the same note we started with.
But a similar piece sung by unaccompanied choir should end up on the "wrong" note at the end.
The question asked about the orbit of a moon. A moon orbits a planet, not the primary. Looks like C to me.
What is C orbiting? are you assuming that A is the orbit of a planet? Where does it say that?
And if it's C then why can't it be D as well. There must be a planet for D to be an orbit.
So you're assuming that A is the orbit of a planet that C is then orbiting but D is just a random circle? Yes I know the examiners expected C but that doesn't make the question any better.
Q19. Huh? Radio signals are analogue.
Are you sure?
Beyond any doubt. Modems, ADSL, Radio are all analogue transmissions.
Quadrature amplitude modulation (QAM) is a modulation scheme which conveys data by changing (modulating) the amplitude of two carrier waves
Now if QAM is digital then:
Phase modulation (analog PM) and phase-shift keying (digital PSK) can be regarded as a special case of QAM, where the amplitude of the modulating signal is constant, with only the phase varying. This can also be extended to frequency modulation (FM) and frequency-shift keying (FSK), as these can be regarded as a special case of phase modulation.
So FM is a special case of PM which is a special case of QAM. QAM is digital therefore FM is digital.
IMO the signal that is transmitted is always an analogue signal and received with analogue electronics and then, for analogue radio, the signal is converted into an analogue signal that "directly" drives the speaker while for digital the signal is converted into a digital signal that is then further processed.
A obviously not true. B&C Hearing deteriorates with age and, barring things like digital hearing aids (if they exist), digital technology has no effect on what you can hear.
Are you joking (or trying), or are you some sort of vinyl buff? It's pretty obvious that the answer is B.
(note: B the quality of sound you can hear) (note: that this is a UK exam paper)
However, in the UK, Denmark, Norway and Switzerland, which are the leading countries with regard to implementing DAB, the vast majority of stereo radio stations on DAB have a lower sound-quality than FM
If it's B "the quality of the sound you can hear" then why not C "the range of frequencies you can hear?" CD has a bandwidth from DC to 20kHz.
Vinyl has a very poor bandwidth, hence the RIAA equalization (yes, that RIAA)
LP on the outer edge with equalization goes from about 50Hz to about 30kHz while on the inside edge the upper limit is about half that.
The upper limit for CD is above the threshold for hearing and for LP it pretty much is (although maybe not for 16 year olds taking this exam). But the lower limit of hearing
The answer is D. One of the main effects of digital processing has been the increase in loudness. This is seen in CDs, on commercial radio where, now that digital processing is simple and cheap, the adverts can be transmitted with a compressed dynamic range and so need to leave much less headroom for the peaks.
Slashdot Mirror
When the stockpile dwindles and the price of helium goes up, I guarantee extraction will take place.
That's ignoring a large part of the issue, which is that the helium is being extracted. It's an impurity in natural gas that can almost always be ignored if you are interested in the natural gas.
Because the natural gas is in demand, it is being extracted. Because there isn't the necessary demand for helium at the moment, there's nobody prepared to pay to separate it from the natural gas and store it. Profit is maximized short term by throwing the helium away, even if the long term maximum benefit is achieved by saving it.
This is unlikely to significantly change in the foreseeable future. The helium price will go up once the US reserves are exhausted, but only to the point where sufficient helium to meet current demand is separated. The rest will still be lost to space.
Unless, and until, the demand for natural gas approximately meets the demand for helium (based on their respective ratios in the gas field) then there will always be one or other wasted if the person doing the extraction is attempting to maximize short term profit. If we had absolutely no use for natural gas but a demand for helium then we'd be throwing the natural gas away instead.
Tim.
I think it's more a case of the bank aren't able to get the IP address of the person who actually set up the DD.
The charity are not allowed to release that information to the bank, even in the case of fraud. Maybe Clarkson has decided to take this hit and has not requested the money back and has not made a complaint to the police.
Therefore there's nothing that the bank can do. Only the police have the powers to request the information that would be needed to investigate this fraud from the charity.
Tim.
Assuming you are in the UK, you write to Amex saying you are cancelling the DD mandate. You CC a copy to your bank.
If Amex ever take money again after that they you contact your bank under the DD guarantee and they must[1] immediately refund the money (you might have to argue a bit with the telephone droids) and then the bank can fight it out with Amex to get the money back.
The thing with direct debits that people don't understand it that they can only be cancelled by the recipient of the money. That sounds dodgy, except that, if you tell the recipient to cancel the mandate then they must cancel it, and, once you've told them to cancel it you've got the cover of the DD guarantee if they ignore your instructions. (Hence why I said CC your bank)
[1] legally, it's not always trivial in practice but always possible.
Tim.
Just has to do with coding methodology. strcpy is insecure, strncpy is more so. strncpy(src, dst, sizeof(dst)) is more secure than strncpy(src, dst, size_of_dst). Those are easy to fix security bugs. Other security bugs are harder to find as you have to trace the myriad of states the app can be in during mem writes.
/* We'll just fit as much of the translated error as possible into this buffer */
strcpy is NOT insecure. It can be used insecurely.
But congratulations, you've just turned what could have been a borderline ok strcpy(src, dst) (ought to have been criticized at code review as the names of the variables are confusing) bit of code into (probably) a crash and definitely a buffer overrun if sizeof dst is larger than sizeof src.
I have lost count of the number of bugs I've had to fix after someone changed a perfectly good strcpy into strncpy. A common mistake is:
strcpy(dst, src);
becomes
strncpy(dst, src, sizeof dst);
and then you get a bug because only the first four characters of src appear in dst followed by garbage.
Of course, then it gets changed to
strncpy(dst, src, strlen(src));
because the original programmer did know what they were doing and the buffer was big enough.
Eventually we get to the brilliant:
strncpy(dst, src, strlen(src)+1);
Fantastic! What an improvement! And yes, it really does happen in what was once good production code because some idiot has heard that "strcpy is insecure".
Another one I've seen is:
dst = malloc(1000000);
strcpy(dst, "MESSAGE");
gets changed to
dst = malloc(1000000);
strncpy(dst, "MESSAGE", 1000000);
Yup, instead of writing 8 bytes, we'll write one million bytes because strcpy is insecure, but we won't fix the missing check for NULL. (there's a fairly good argument for not checking the return from malloc in much production code - if malloc actually fails then you're already so far up shit creek without a paddle that it's probably impossible to recover gracefully anyway. Obviously different considerations will apply if you're controlling a nuclear power plant than if you're writing a game)
strncpy is NOT a replacement for strcpy with a length parameter. Unfortunately strncpy has a very bad name, it should be called something like meminit_from_str() as strncpy ALWAYS writes n bytes and doesn't always write a null terminator. (I've also had to fix bugs where someone has replaced a correct use of strncpy with a version that guarantees to write the null)
strncat is a possibly safer replacement for strcat. However, the length parameter is so tricky to get right that I've seen cases where someone originally wrote strcat safely, that got changed to strncat "because it's safer" and then a bit later another change was made that caused a crash because the original change to strncat got the length parameter wrong.
extern char error_msg[][40];
char error[64];
strcpy(error, "ERROR");
strcat(error, error_msg[e]);
becomes
strncpy(error, "ERROR:", sizeof error);
strncat(error, error_msg[e], sizeof error - 6);
becomes
strncpy(error, get_translation("ERROR:", lang), sizeof error);
strncat(error, translated_error_msg(e, lang), sizeof error - strlen(error));
of course, even more common is to miss the -6 or strlen(error) completely than to remember the extra -1 that is required on the length parameter.
(The man pages are IMO, confusing for strncat as they usually say something along the lines of "appends at most n characters")
Tim.
Riemann.
:-) ). But maybe I should shorten my sig to 'God said "dF=0," and there was light' just in case ;-)
I think you mean Gauss.
But seriously -- how would one get in touch with you?
It's not me but Google is your friend. You can find some rather interesting threads. Including one where someone says that knowledge of differential geometry is necessary:
http://www.wilmott.com/messageview.cfm?catid=34&threadid=36727
about half way down.
Quite frankly I'm at something of a loss to imagine what outside of research would actually have a use for differential geometry (maybe I wouldn't be suitable for a job
Tim.
OK - fine. How many parts per million of uranium is there in sea water, eh? Now, take the number of parts of Uranium you will need to run a reactor. Multiple those two numbers, and you will get the volume of water you will need to boil off to get the uranium you need for ONE reactor.
About 3 parts per billion
That's the first I've ever heard about anybody being crazy enough to try to boil off the water to extract the uranium.
http://jolisfukyu.tokai-sc.jaea.go.jp/fukyu/mirai-en/4_5.html
If 2g-U/kg-adsorbent is submerged for 60 days at a time and used 6 times, the uranium cost is calculated to be 88,000 yen/kg-U, including the cost of adsorbent production, uranium collection, and uranium purification. When 6g-U/kg-adsorbent and 20 repetitions or more becomes possible, the uranium cost reduces to 15,000 yen. This price level is equivalent to that of the highest cost of the minable uranium. The lowest cost attainable now is 25,000 yen with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses. In this case, the initial investment to collect the uranium from seawater is 107.7 billion yen, which is 1/3 of the construction cost of a one million-kilowatt class nuclear power plant
So, of the order of $1bn to setup and then around 250$/kg to extract using current technology to extract enough uranium to run 6 nuclear power stations.
Tim.
How is maglev better anyway? So you reduce your rolling friction to zero, what do you save? 1% of total operating power? You'd spend a lot more if your using electromagnets to keep the 'lev' action going...
Mainly it's the dynamic loading on the rails that is the problem with trains going faster and faster.
A maglev is like a hovercraft with the load spread out over the full length of the train. A tiny imperfection in the rail doesn't cause every passing carriage to hammer at it, reducing the need for rail inspection and maintenance.
IMO, the biggest advantage of maglev is that it automatically implies the advantages that the French were far sighted enough to acquire with LGV - that there are dedicated lines for the high speed trains with no sharing with slow traffic. I was on a 225 yesterday from Durham to London which was on time until the last 50 miles or so when we got stuck behind a slow train and we had to wait until it had pulled into Stevenage before we could get back up to speed. That added ten minutes to the journey in the last half hour or so.
Tim.
Then, is it the customer's fault that his ISP is grossly overselling their capacity?
And if their customer wants to download web pages in seconds but doesn't want to download GB of porn/p2p whatever?
The problem ISPs are having is that they don't want to impose hard limits on how much their customers can download each month because (almost) everybody's usage varies from month to month. A customer (me) who might download 2Gb/month usually might then suddenly download 5Gb in a few hours (new Debian release)
I even try and push as much of my usage as possible into the early hours.
The problem is commonly known as tradegy of the commons
It will make very little difference to me, or to most internet subscribers, if ISPs start imposing hard limits on the amount people can download.
Tim.
FYI, ERA asks BPI to drop DRM ASAP.
Something like that is just crying out for an acronym.
FEABTDDA (pronounced FeabTaDa perhaps?)
Tim.
But what I can't fathom is the animal-like need for vengeance against the poor government employees who lost the data as the result of one of these accidents.
This is the UK. Typically, unless the employee is criminally negligent the liability would fall on the employer even if the employee had broken the employers rules - e.g. leaving the laptop unattended in a car.
The employer will be expected to take reasonable steps to prevent data loss as a result of carelessness of employees - typically this would mean that if employees need to take data home the employer would provide a laptop that had disk level encryption. (Its unlikely that the employees mistake would even be grounds for dismissal unless it was a repeated offence)
Obviously there are grey areas, but I would expect "just" putting the data in an encrypted zip archive and expecting the employee not to decrypt it and keep it decrypted on the laptop would not be a defence - which is why I suspect disk level encryption is going to be required.
Tim.
Worcester is pronounced Wusta ... ?!?!? They haven't just evolved - they've completely morphed!
The pronunciation probably dates back to before there was written English.
Towcester = toaster
Gloucester = glosster
Leicester = lester
I think Towcester at least goes back to the stone age although the name has changed over the millenia.
Then there are names like Featherstonehaugh-Cholmondeley = Fanshaw-Chumley (although I think the hyphenation is more a case of "Just think if a Featherstonehaugh married a Cholmondeley")
St. John = sinjin http://en.wikipedia.org/wiki/Norman_St._John-Stevas
Caius = keys http://www.cam.ac.uk/admissions/undergraduate/colleges/caius/
Dalziel = deyell http://en.wikipedia.org/wiki/Dalziel
Menzies = mingiss http://en.wikipedia.org/wiki/Sir_Menzies_Campbell
Tim.
From the linked article:
In addition, New Horizons spotted the infrared glow from at least 36 Io volcanoes, and measured lava temperatures up to 1,900 degrees Fahrenheit, similar to many terrestrial volcanoes.
Tim.
Ah! That's very interesting thank you.
We don't get that at all in the UK. I _think_ there is still a married couples allowance which, can be applied to either the husband or wifes income (or shared)
But all the other allowances are per person. So if the husband is earning 40k and the wife is earning nothing then no account can be taken of the wife's allowances. This means that a couple both earning 20k are better off than one person earning 40k and the other earning nothing. (There are things called family income tax credits that I don't know anything about that might - or might not - even this out)
We also have a tax called Capital Gains Tax. Basically anything you buy and then sell again is assessed for tax (shares and property are probably the most common). There is a 9k/year allowance and if your gains are below that then you don't need to declare them. I also think some things are excluded (cars for example - so you can't use the loss on changing your car every year to offset gains elsewhere)
Your main home (personal private residence) is exempt from CGT.
Even if you give something away you are still taxed as though it was sold at full market value (gifts to charity are free of CGT). However husband and wife are allowed to transfer stuff between themselves without triggering the CGT tax.
Very much like how I understand American taxes work, all this tends to benefit the well off. Most families are completely unable to take advantage of their CGT allowances. Even if you assume the stock market grows 10% p.a. You'd need 90k invested per person. (No CGT on pension funds but there's still a 10% dividend tax that cannot be claimed back)
But couples who do have significant assets can often move them to the lower taxed person and so take advantage of their tax band. So, a couple with one person with an income of 100K plus say another 100K in equities making a dividend of 4k/year can transfer the equities to the non-earner and then get that dividend free of tax. Then when they come to sell they can transfer some of the equities back in order to take advantage of both peoples 9k CGT allowance. But a couple with one earner earning 30k who can't really save significant amounts have absolutely no way to take advantage of the non-earners allowances.
Tim.
This might be true. But a first rate, confident, programmer in the IT industry who isn't on a super high salary in the City (earning well in excess of 100k) can just jump ship.
I've had to do it a few times.
1. I made a huge mistake going to work for one company (I probably partially overlooked the danger signs because they offered me a base salary 33% higher than I was getting). Within two weeks I realized I'd made a mistake going to work for them. Within six weeks I'd moved on and got another (smallish) salary increase. (I actually asked to be released from my four week notice period but the company asked me to do two of them to finish off what I'd been working on otherwise I'd have been gone in four weeks)
2. I was (unexpectedly - fallout from the
Tim.
and renting a moderate apartment is about $1,800 per month
To give you some idea of what prices are like in London, I'd just assumed this said
and renting a moderate apartment is about $1,800 per week
I've managed to find:
Walburgh Street, Aldgate, E1
Total Sq Ft: 533 (49 Sq M) approx.
Bedrooms: 2 bedrooms
For 250GBP/week
To give you some idea of what is available at the low end.
And at the high end:
De Vere Gardens, Kensington, W8
Total Sq Ft: 1,158 (107 Sq M) approx.
Bedrooms: 1 bedroom
For 1000GBP/week
Tim.
In the UK it's approximately:
0% for 0 to 7000 EUR
10% for 7000 to 10000 EUR
22% for 10000 to 53000 EUR
40% above 53000 EUR
Additionally we have Employees National insurance
0% below 7000 EUR
11% for 7000 to 47000 EUR
1% above 47000 EUR
And employers National insurance (Which the employer pays but doesn't appear anywhere on your payslip)
Which I think is
12.8% on everything.
(The employers NI doesn't affect your take home pay - if you earn 100000 before tax you will pay approx 28000 Tax, 5000 NI and take home approx 67000. Your employer will pay an additional 12800 NI so the overall income tax rate is either 33000/100000 = 33% or 45000/112000 = 40% depending on how you account for the employers NI)
Then there's VAT at 17.5% on almost everything.
Contributions to a pension scheme are paid gross (but employers NI is still paid)
Perks such as health insurance are taxed as though they were income but you don't pay any more NI.
House prices vary a lot. In London, average house prices vary from 1M GBP (1.4M EUR) in Kensington and Chelsea to as little as 200K GBP 280K EUR in Barking and Dagenham.
http://news.bbc.co.uk/1/shared/spl/hi/in_depth/uk_house_prices/counties/html/county37.stm
Tim.
The problem comes about because the police don't have a clue.
Consider the scenario. You are arrested for a crime you didn't commit. Fortunately, despite the police trying to pin it on you, the real culprit confesses and you are released without a stain on your character.
Then a little while later you are arrested again because your fingerprints (which were only stored because you were incorrectly arrested before) are found on some recovered stolen mail. The only problem being that you were the _VICTIM_ of the theft. Yes! Your fingerprints were on the mail because you _POSTED_ it!
No attempt by the police to investigate. Finger print match. Call the person in to the station. Arrest them immediately. And then tell them to accept a caution to get it over with!
Think it's a tall story?
http://www.blackpoolgazette.co.uk/ViewArticle.aspx?SectionID=62&ArticleID=1361138
Tim.
The debian etch 2.6 kernel will run on a 12Mb 486DX2-50 machine. What won't work is booting with the default initrd that apt-get install creates but if you strip that down it will boot fine.
Tim.
The "metric martyrs" got into trouble because they _refused_ to sell using metric units.
There's absolutely no problem about a butcher selling a "pound of steak" to someone who asks for it (although the receipt will have to show 454g).
But
"If people, particularly the young who have never been taught pounds and inches, want to shop in units that they understand, why shouldn't they?"
Is what the "metric martyrs" want to prevent.
Tim.
much as a pint of water weighs a pound (the world around, and takes 1 BTU to raise temperature by 1 degree F).
You've got a strange definition of world there.
On this side of the pond:
"A pint of water weighs a pound and a quarter"
I'm ashamed to have to say that it appears the majority of my countrymen would prefer to use "fundamental" units that have rhyming mnemonics rather than units that make all the calculations simple and consistent across the world.
http://news.bbc.co.uk/1/hi/uk/6637587.stm
Tim.
Our scale is based on the twelth root of two. (Thus the octave, a factor of two, is broken up into twelve steps.) It's a convenience to let us have instruments that can play in many different keys without needing to be re-tuned.
:-) )
;-)
No, this isn't right.
The modern piano is typically tuned with a stretched octave. The style and size of piano will determine the amount of stretch together with the type of room and type of music to be played to an extent. (In general, the larger the piano the less the stretch)
Tuning a piano well (ignoring the maintenance etc that a good piano tuner will also do) is very much a skill depending on an excellent ear and good musicality and not something that can be done with a frequency meter.
There is a very good reason top pianists take their piano and piano tuner with them when touring.
I was acting as an usher and general person helping out when Sviatoslav Richter performed in the Holywell Music Room after collecting his honourary doctorate at Oxford. The Steinway was moved out into a back room and his Yamaha installed. His tuner then tuned it up, he played a few little bits and then the tuner completely retuned it (tiny adjustments that I'm not sure I could actually hear). All to perform, IIRC, one Hayden piano sonata. (He then cancelled his concert in the QEH or Barbican - can't remember which - the following night because he was exhausted from all the excitement in Oxford
I later got a chance to play on his piano (after his death) at the Music Messe in Frankfurt. I'm certain that the only reason my playing didn't sound as good as his was I didn't have the piano tuner retune to match my style of playing and the room.
Tim.
G# and A#/B-flat are frequently wrong, and tend to be wrong in the same direction. They haven't proven orchestra-tuning is the case, it's just their hypothesis that the blurring around A is likely due to that factor.
Just as likely that these are the ones that are the most out of tune.
In a good orchestra, A# and B-flat and G# and A-flat won't even have the same pitch in the same piece even if the orchestra is tuned to A-440. (Obviously if they are playing a piano concerto then the orchestra will tend to play a bit more out of tune so they will converge)
Tim.
12-tone system is a man-made invention
Not really.
The (perfect) octave, fourth and fifth are natural harmonics. So natural, infact, that if you silently hold down a G and then strike the C an octave and a half below the G will start to audibly resonate (even though on the piano the G is slightly out of tune compared to the C)
Twelve consecutive fifths (and I'm using consecutive here to mean going up a fifth, then another fifth etc rather than it's musical meaning) will (almost) bring you back to the original note but 7 octaves higher.
Twelve consecutive fourths will (almost) bring you back to the original note but 5 octaves higher.
Other intervals also have rational ratios.
Major third = 5/4
And if you look at the harmonics of the fundamental:
1 - Fundamental
2 - Octave
3 - Fifth (3/2)
4 - Octave
5 - Major third (5/4)
And as an aside, the clarinet only has odd harmonics, therefore the upper register is an octave and a fifth above for the same fingering.
A bell has a resonance a minor third (6/5) below the fundamental.
(The minor third is the interval between the major third and the dominant: 3/2 / 5/4 = 6/5)
Tim.
JS Bach was one of those who worked on a solution to this, and he came up with the modern even-tempered scale, which averages out the intervals so that all keys are equally in-tune (or out-of-tune).
Actually Bach came up with the well-tempered scale. The equally tempered scale is just a special case of the well-tempered scale (and I'm pretty sure Bach wouldn't have written his 48 if he'd really intended an equally tempered scale. He'd have written one major and one minor piece transposed into 12 keys each)
If it weren't for being well-tempered, anybody could tune a piano - infact it would be fairly simple to design a robot to do it but a good piano tuner will tune a piano to suit the room and the type of music being played and not rely on electronic tuning except maybe for the first note.
If you have a well-trained ear then you can hear the slight beating that indicates this slight out-of-tuneness when you strike an open fifth on an even-tempered instrument (such as a piano). String and wind players are of course able to make the slight adjustments to overcome this tuning compromise, and if you listen to a really good string quartet you can sometimes hear the difference.
And singers. My partner can sing a full cycle of descending fifths (jumping up an octave where necessary) and arrive at exactly the "wrong" note.
(for non-musicians, a perfect fifth has a frequency 3/2 and a perfect octave 2x the fundamental. A perfect fourth is 4/3. (Note a fourth plus a fifth = 4/3*3/2=2=a perfect octave) (she finds this easier to sing repeated descending fifths but we can pretend a descending fifth is an ascending fourth plus an octave jump)
Going up a fourth 12 times brings us back to the same note (5 octaves higher) but:
going up 12 fourths (4/3)^12 = 31.56929 while going up 5 octaves:
2^5=32.
So these are the same note arrived at via two different routes and going up in fourths the singer arrives back at the tonic about a quarter semitone flat as compared to the piano.
I've always wondered what people with perfect pitch do in this circumstance. I think one of the Beethoven piano sonatas has a complete cycle of fifths. Obviously, on the piano there are 12 tiny errors that mean at the end we're on the same note we started with.
But a similar piece sung by unaccompanied choir should end up on the "wrong" note at the end.
Tim.
What is C orbiting? are you assuming that A is the orbit of a planet? Where does it say that?
And if it's C then why can't it be D as well. There must be a planet for D to be an orbit.
So you're assuming that A is the orbit of a planet that C is then orbiting but D is just a random circle? Yes I know the examiners expected C but that doesn't make the question any better.
Beyond any doubt. Modems, ADSL, Radio are all analogue transmissions.
I believe DAB uses QAM on each of the subcarriers. From http://en.wikipedia.org/wiki/Quadrature_amplitude
Quadrature amplitude modulation (QAM) is a modulation scheme which conveys data by changing (modulating) the amplitude of two carrier waves
Now if QAM is digital then:
Phase modulation (analog PM) and phase-shift keying (digital PSK) can be regarded as a special case of QAM, where the amplitude of the modulating signal is constant, with only the phase varying. This can also be extended to frequency modulation (FM) and frequency-shift keying (FSK), as these can be regarded as a special case of phase modulation.
So FM is a special case of PM which is a special case of QAM. QAM is digital therefore FM is digital.
IMO the signal that is transmitted is always an analogue signal and received with analogue electronics and then, for analogue radio, the signal is converted into an analogue signal that "directly" drives the speaker while for digital the signal is converted into a digital signal that is then further processed.
(note: B the quality of sound you can hear)
(note: that this is a UK exam paper)
Quote from the wikipedia page on DAB: http://en.wikipedia.org/wiki/Digital_Audio_Broadc
If it's B "the quality of the sound you can hear" then why not C "the range of frequencies you can hear?" CD has a bandwidth from DC to 20kHz.
Vinyl has a very poor bandwidth, hence the RIAA equalization (yes, that RIAA)
LP on the outer edge with equalization goes from about 50Hz to about 30kHz while on the inside edge the upper limit is about half that.
The upper limit for CD is above the threshold for hearing and for LP it pretty much is (although maybe not for 16 year olds taking this exam). But the lower limit of hearing
The answer is D. One of the main effects of digital processing has been the increase in loudness. This is seen in CDs, on commercial radio where, now that digital processing is simple and cheap, the adverts can be transmitted with a compressed dynamic range and so need to leave much less headroom for the peaks.
Tim.