×

Announcing: Slashdot Deals - Explore geek apps, games, gadgets and more. (what is this?)

Thank you!

We are sorry to see you leave - Beta is different and we value the time you took to try it out. Before you decide to go, please take a look at some value-adds for Beta and learn more about it. Thank you for reading Slashdot, and for making the site better!

Comments

top

Who Unfriended You, and Why

sadtrev Re:TFA is evil (122 comments)

Interestingly, Facebook doesn't seem to make unfriends too easy to find - they consider the greasmonkey script to be "abusive or spammy" and won't allow me to forward it to somebody within the fb message service.

more than 3 years ago
top

Opera Supports Google Decision To Drop H.264

sadtrev Re:Everyone else uses H264/MPEG4 (336 comments)

still-image compression is not a field where large gains can be had so easily.

JPEG has two significant practical deficiencies which are not inherent in its lossy nature

  • firstly it's 8-bit channel depth is not enough to allow any editing without noticeable degradation,
  • and secondly, its compression characteristics tend to enhance photo grain and silicon array noise.

I guess that the reason that something better hasn't emerged is the combination of the patent thicket around wavelets, and all the shenanegans the digital camera manufacturers have been playing with raw formats.

more than 3 years ago
top

Jaguar's Hybrid Jet-Powered Concept Car

sadtrev Re:Should be reliable (334 comments)

The Rover gas-turbine car was almost ready for launch (in the mid-'60s). It was cleaner, quieter and potentially cheaper than cars with conventional reciprocating engine designs.
It did have two major disadvantages - unreliability due to brittleness of the heat exchanger, and
- the tendency to singe the paint off cars that approached too close to the exhaust.

more than 4 years ago
top

The Last Component To Fail In My Computer Was The...

sadtrev Re:Last component to fail? (715 comments)

I think the question was meant to be "most recent to fail".
I struggled for a while trying to understand the question as it was posed and failed.

the question, as posed is as meaningless as "the most recent not to fail"

more than 4 years ago
top

"Digital Universe" Enters the Zettabyte Era

sadtrev What is the data? (137 comments)

I was told about 10 years ago that "70% of the world's digital data is stored under MVS" which surprised me a bit, even then.
After some thought when you consider that almost all commercial transactions (banks, telcos etc) whould have been running MVS then it may have been true.
SETI and CERN and other large scientific endeavours are small fry in comparison.

more than 4 years ago
top

MATLAB Can't Manipulate 64-Bit Integers

sadtrev Re:Especially since someone has implemented it.... (334 comments)

using 64-bit integers instead of floats is a common trick in embedded C for control and signal processing on low power processors. I have experience of four different embedded systems used in commercial products from three different companies I've worked with - three of the four used 64-bit integers for roundoff-sensitive calculations.
I was a bit surprised that Matlab can't handle this, but then I've seen the poor quality of the ostensibly production-ready code that comes out of their M2C converter - it was about ten times the code footprint and a fifth the speed of a minimally-optimised C version of the same algorithm.

Honestly, I don't know how anyone can justify paying for this, when R (and even Octave in this instance) is more capable. Where the target platform requires C or asm code, then doing development in Matlab is usually more trouble than it saves. The graphs are prettier, though.

more than 4 years ago
top

Paper Manufacturer Launches "Print More" Campaign

sadtrev Re:I don't worry much about paper (446 comments)

These days paper, as is used in laser printers etc. is not made mostly from wood. It is mostly made from bulking agents like calcium carbonate, which have to be ground to typically 2 micron or finer, and then dried at huge energy cost.
The wood fibers are just there to keep all the bulk together, and are a small portion (sometimes as little as 10%) of the weight of a sheet of paper.

You may have noticed that this sort of paper leaves a lot of ash when burnt.

more than 4 years ago
top

Rugged Laptop/Tablet Suggestions, 2010 Version?

sadtrev Re:Use a disposable laptop (249 comments)

Fine sand is a killer - it gets everywhere.

I used to work on powder processing instrumentation and regularly had to take laptop computers onsite to calibrate instruments. We used to use Dells with external IP-54 keyboards and masking tape over all the unused ports. On a few occasions I had to take a normal keyboard they didn't last more than a few keystrokes (I'd guess 20 per key before they failed).

This was lactose, coal, silica, calcium carbonate, etc. When we started work with metal powder we invested in proper IP54 laptops - no fan, membrane keyboard and rubber plugs on all the ports. Heavy, underpowered (800MHz PIII) but they worked. We looked at some "ruggedised" efforts but without the IP rating they were really just slightly less prone to drop damage.

more than 4 years ago
top

Microsoft "Courier" Pictures

sadtrev yes, (230 comments)

but does it run Linux?

more than 4 years ago
top

Using Classical Music As a Form of Social Control

sadtrev Re:It'll stop in a few years (721 comments)

The good bits of "Mozart's Requiem" were written by one of his students after he died in order to help pay his debts.

The only other half-decent stuff attributed to him are the 40th Symphony and the Magic Flute overture, also written in the three months whilst he was kicking the bucket. Makes me suspect that somebody else wrote them for him as well.

more than 4 years ago
top

Plug vs. Plug — Which Nation's Socket Is Best?

sadtrev Re:US vs UK... (1174 comments)

Having lived in the US, UK, Malaysia and France, I would concurr that the British plug system is far better. It was properly thought, and universally implemented across the country 50 years ago using an act of parliment on the premise that using anything else was dangerous and therefore potentially negligent. More features have been added since then (including household earth-leakage trip sensing).

I've had problems with a French pin snapping in a socket leaving an exposed live pin for my 3-year-old son to play with (luckily I spotted it in time and managed to cover it).
In the US I almost got used to the risk of shocks off electrical appliances. I also had a lab fire destroy some of my work because somebody had knocked out the cable of the pump supplying the coolant.

In Malaysia where the national standard specifies the british plug type, the biggest issue was that cheap Chinese imports sometimes didn't use it.

When basic safety is involved, I don't think that it's over-engineering. Your comment about extra points of failure doesn't make any sense.

about 5 years ago
top

The Incredible Shrinking Genome

sadtrev smaller code size without copy& paste (113 comments)

Body temperature control is very effective in reducing the number of different enzymes that need to be coded for.
Frogs, for example have ~8x more genes than humans - partly because they have lots of different enzymes that do the same thing but at different temperature.

more than 5 years ago
top

Alan Cox Leaves Red Hat

sadtrev Bu cryn newid mewn deng mlynedd (163 comments)

I first stumbled on Slashdot ten years ago when Alan Cox mentioned in his online diary (a novelty in those days) that it was nice that even Slashdot were carrying it as a story.

I knew Alan from my uni days when I heard the outrageous rumour that SUCS (the comp.soc.) were trying to put real Unix onto a PC.

more than 5 years ago
top

Collimating Semiconductor Lasers Without Lenses

sadtrev Re:Steering laser beams (136 comments)

Raw Diode Lasers produce a highly elliptical output which makes it inefficient to couple to a round fiber. It is possible to reduce the astigmatism with fancy lens designs, but this needs to be very close to the die. Even then, the output won't be anywhere near as clean as a gas laser.

This development sounds like a neat and robust way of doing what had previously be done with carefully assembled, and glued lens - pinhole -lens arrangements.

more than 6 years ago

Submissions

sadtrev hasn't submitted any stories.

Journals

sadtrev has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?