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!



Bidding In Government Auction of Airwaves Reaches $34 Billion

pehrs Re:Who ends up paying for this? (82 comments)

What makes you think that it would be any cheaper if the teleco's got spectrum worth billions for free?

3 days ago

Bidding In Government Auction of Airwaves Reaches $34 Billion

pehrs Re:Not sure if it adds up (82 comments)

We tried that. It's called "beauty contests". There have been plenty of those, specially with the spectrum allocations in Europe the 1990ths.

They tend not to give very good outcomes. It is much easier to hold companies to paying a certain sum than it is to hold them to promises, especially after a few years of restructuring and consolidation in the market. In many cases companies have been sitting on huge chunks of spectrum without doing anything, sometimes just paying the fines for returning the spectrum after a while. In addition, the rules and ruling in beauty contests tend to become hives of corruption.

Beauty contests may be a good idea in some emerging markets where there is very little incentives to pay for spectrum. In the rest of the world, let the market decide what the spectrum is worth, and let the teleco's pay through the nose for the spectrum. There is no reason to give away something that valuable.

3 days ago

Sweden Considers Adding "Sexism" Ratings To Video Games

pehrs Re:"Swedish Video Game." (641 comments)

You have no idea of what impact Sweden has on the computer game market, do you? Sweden is a big player in the computer game industry. Companies like Avalanche, EA Dice, GRIN, King, Massive, Mojang, Overkill, Paradox and Starbreeze are all based in Sweden.


about two weeks ago

SpaceShipTwo's Rocket Engine Did Not Cause Fatal Crash

pehrs Re:Then how did the pilot die? (150 comments)

Eh? No, the crew of Columbia did not survive all the way down. Perhaps you are thinking of challenger, where there is some debate on if they survived until impact. In the case of Columbia the crew was dead four times over before impact. The lethal factors NASA identified were:

1. Depressurization of the crew module at or shortly after orbiter breakup.
So, we start with denying the crew oxygen. None closed their helmets when pressure dropped to 0 in a fraction of a second at the start of the breakup.
2. Exposure of unconscious or deceased crew members to a dynamic rotating load environment with a lack of upper body restraint and non-conformal helmets.
Then we bang them around a bit in what can be best described as a rolling garbage compressor full of sharp and heavy things, in helmets not designed to protect against this kind of force and without proper seat belts.
3. Separation of the crew from the crew module and the seat with associated forces, material interactions, and thermal consequences.
Then we break the box apart, exposing the crew to an unprotected reentry into atmosphere
4. Exposure to near vacuum, aerodynamic accelerations, and cold temperatures.
Finally we let them free-fall back to earth...

The Columbia Crew Survival Investigation Report is a 400 page long and very dark document, but the executive summary is just a couple pages. You can find it here:
http://history.nasa.gov/columb... The bodies of the astronauts were mangled beyond recognition, which is hinted in the report, but out of respect of the astronauts details of the injuries are redacted from the report.

about three weeks ago

The Most Highly Cited Scientific Papers of All Time

pehrs Re:results from different practices among discipli (81 comments)

In engineering, there tends to be less of a tendency to cite a paper with methodological info: Very few people using an FFT cite the Cooley-Tukey paper; likewise, someone talking about using an ADC for sampled data isn't going to cite Nyquist, even if they say "the sampling rate was 5 time the Nyquist frequency". Likewise, in engineering, you don't see: The dice were attached to the substrate using a eutectic mixture of lead and tin as recommended by Agricola in "de re Metallica".

Yes and no. In computer science experienced authors rely on a common and rather broad knowledge base when writing their publications. There is a tradition not to cite things which are part of the common knowledge. I would not cite just because I was using the FFT, unless I was doing something out of the ordinary with it which actually requires understanding all the details of the original publication.

A very common sign of an inexperienced author is sloppy references. Typically there are too many references, and to works which are not strictly relevant for the author. When you see an introduction with 60 references outside a survey you can usually toss the paper in the trash bin and tell the authors to start over...

about a month ago

David Cameron Says Brits Should Be Taught Imperial Measures

pehrs Re:Idiot (942 comments)

The only problem with that is that there are at least 3 definitions of cup that I know of (metric, imperial and U.S. customary), which kind of defeats the purpose of having a recipe in the first place.

And the approximation problem is something you constructed for yourself. Here we typically describe recipes using deciliters. Which is a nice, standard unit which you can scale up or down as needed. And, no, we don't start with imperial measurements and round off. If you want to do scones my way you will have to add 1.26 cups of standard milk, 3.38 cups of flour and 0.22 lb butter (among other things).

about 2 months ago

Ebola Quarantine Center In Liberia Looted

pehrs Re:Please stop and think (359 comments)

A good and insightful post.

The only thing you forgot is to mention why Liberia is one of the most miserable parts of Africa.

Liberia is the only country in Africa founded by United States colonization while occupied by native Africans. It was financed by the American Colonization Society, an organization created to remove unwanted freed black slaves from America, to avoid a slave uprising like what happened in Tahiti. The colonizers became known as Americo-Liberians and promptly started to enslave the locals and selling them back to the US (with support from the American Colonization Society). The Americo-Liberians, led the political, social, cultural and economic sectors of the country and ruled the nation for over 130 years as a dominant minority. The atrocities under that regime were too many to count.

The US continued to keep it a hell hole in the effort to fight communism, and from 1940 and forward pumped enormous sums into the budget country (about half the GNP was American aid for a while...). Of course most of this money vanished in corruption. But in return the evil communists were kept out. Eventually there was a coup in 1980, finally removing the Americo-Liberians, and starting two civil wars, killing about half a million and displacing about half of the country population. About 85% of the people live under the poverty level today.

We sometimes speak of the Ghost of King Leopold, after the horrors in Congo. But when it comes to colonialism the American version seen in Liberia was at least as bad. And by doing it as a private enterprise they ensured that, unlike the state colonies, there never was a decolonization with support for forming a stable state.

about 3 months ago

Point-and-Shoot: TrackingPoint's New Linux-Controlled AR-15s

pehrs Re: Apply liberal amounts of gloss. (219 comments)

You would be surprised how bad people shoot in the real world... I hunt. I fire about 50 shots on big game (mostly boar, deer and moose) a year, and well over thousand if you count small game. I compete, primarily in sporting and skeet but also 300 meter rifle.

In my experience the wast majority of shooters have a hard time hitting a deer sized targets with a rifle at 300 meters without special training. Add any sort of complication, like a little bit of stress, moving target, bad light or the like, and most people won't hit a deer sized target consistently (that is, 10 out of 10 in the heart-lung area) at 100 meters. The performance of the cartridge barely matters. Most people simply need a lot of training to aim and fire a rifle well, especially under stress.

I spend a considerable amount of my spare time tracking down deer which were wounded by people with the "Any dope can make a 300 yard shot" attitude. They are typically not quite so tough at 4 am in the morning when we have spent a few hours tracking down the deer they wounded. While it is good training for the dogs, and it is very rewarding work, it would be better if people learned how hard it is to shoot well on distances over 100 meters.

about 4 months ago

A Skeptical View of Israel's Iron Dome Rocket Defense System

pehrs Re:Subject bait (379 comments)

Railroad ties make decent improvised shelter roofs.

Decent but not good. They are likely to create really nasty shrapnel if hit. They are heavy. And they are typically covered with creosote, which is something you do not want in your home if you can avoid it. In general, wood may be cheap, but it's not a very good material for building shelters against explosives..

If you spend the time and energy building a bombshelter you use the right materials, which are typically steel and reinforced concrete.

about 4 months ago

The World's Worst Planes: Aircraft Designs That Failed

pehrs Re:Does not matter (209 comments)

I see your Goblin, and raise you a De Lackner HZ-1 Aerocycle.

The operator is standing on an open hub platform on top of a helicopter rotor. What could possibly go wrong?

In the military we have a word for that kind of contraption. It's "Skeet".

about 6 months ago

Xbox One Reputation System Penalizes Gamers Who Behave Badly

pehrs Re:Bullying (183 comments)

Having been involved of the design of a similar system a few years back, I found this remarkably easy to handle.

What you do is that you cluster people based on their opinions, and add a fading of old opinions. People who share good opinion about each other are in the same cluster. People who dislike each other are in different clusters. So, what happens in the end is that the "nice" people end up in a few big "nice people" clusters, and you get lots of small clusters of jerks. In the system we designed we actually provided individualised feedback to the users, as in "From the perspective of your cluster, this person has good/neutral/bad standing". In practice it didn't take long before people with good behaviour were efficiently separated from the rest.

Giving bad score to lots of people needlessly quickly gets you kicked out of the "good people" cluster. Congratulations, you now get to play with the rest of bullies.

Of course, this is just basic computer science and statistics...

about 8 months ago

Child Porn Arrest For Cameron Aide Who Helped Plan UK Net Filters

pehrs Re:victimless crime (205 comments)

<quote><p>How is the possession or viewing of child porn a crime at all? I dare someone to prove the harm in possessing/viewing cold porn</p></quote>

There are a lot of problems with many child pornography laws, but there are also very good cases to be made for banning possession and viewing of it.

1. If there is a market for child pornography there is a stronger incentive to abuse children. People will produce more of it where it is actually legal to produce (or the legal system is too weak to stop it).

2. There is a strong stigma connected to being presented in pornography. This stigma and the associated injury does not decrease with time. Those who have experienced it describe it as a form of constant, ongoing, abuse that they have to live with their whole life. While you may not mind people jacking off to pictures of children, it is not something the children in the picture can consent to.

about 9 months ago

EU Proposes To Fit Cars With Speed Limiters

pehrs Re:No need for cameras. (732 comments)

I believe all major producers of cars have active safety systems, using proximity sensors to reduce the risk of accidents. For example Volvo has the City Safety system, which automatically breaks the car in case you get close enough to a car in front that there is a collision hazard. While it won't prevent all accidents it reduces the risk of an accident.

So, it's a nice idea, it works, is implemented and you can buy it with your new car for a reasonable sum ;)

about a year ago

Ask Slashdot: How Do You Prove an IT Manager Is Incompetent?

pehrs Management consulting... (331 comments)

Management consultant does this all the time. It really is a task for somebody focusing on management and organization, not on technology consultant. So call some nice people at a company like Arthur D. Little, McKinsey or similar. Of course, they will charge a lot to sort out this kind of situation.

If you really want to get into management consulting the easy path is typically to toss out all the value words and feelings you may have about the people involved. Don't even think words like "loathed", "ineffective", "parroting" etc. Instead you go to the hard facts. What is the properties of the department? How does it compare to other similar departments? Do they have procedures and routines? What are they? Do they have qualifications in relevant fields? etc. Don't fall in the trap of trying to pin everything on a single person, as this kind of situation is typically part of the culture of the department. The head of the department is a symptom, not the single cause of it all.

Also remember, that those that hired you are probably also responsible for hiring that head of department. Calling him incompetent is roughly the same thing as calling the people who hired him incompetent. Not a good way to build professional relationships or helping people.

about a year and a half ago

Astronauts Fix Phantom Space Station Ammonia Leak

pehrs Re:Wetware Controller advantages (54 comments)

If you remove the humans you can also remove the large, heavy and complex life support systems they need. The life support systems are a major consumer of power on the ISS, and a reason they have so many solar panels that can fail, as well as a constant source of small and large breakdowns in itself.

In the end it is a matter of what you want to do with the spacecraft. Unmanned spacecraft are cheap and reliable. Manned craft are a little more flexible, but expensive and unreliable. Even with the ability to repair stuff humans have they are hampered by the lack of tools and spare parts in space, so it's very unlikely that manned spacecraft will ever be as reliable as the simple robotic probes.

about a year and a half ago

A Sea Story: the Wreck of the Replica HMS Bounty

pehrs Re:Epitath (184 comments)

I have worked on navy and civilian ships, and I can't imagine going to sea with sawdust or wood chips in the engine room. Doing it in heavy weather is unthinkable and the thought sends a shiver up my spine.

Maintaining a ship takes time and dedication. In the time of the tall ships they had the boatswain and the carpenters. Today we have the chief and the engineering staff. An experienced seaman in either position would probably have stopped this trip, and that is one very important reason that the chief should be on equal standing with the captain.

about a year and a half ago

NY Times' Broder Responds To Tesla's Elon Musk

pehrs Re:The reporter does not like electric vehicles (609 comments)

I am not sure what fuzzy fantasy world you life in, where data is TEH INCORRUPTABLE NUBERZZZ!!!!, but the data I regularly handle can be tampered with, use strange units, measure the wrong thing, use a weird scale and so on regardless of being presented as numbers or as charts. A bit of rounding and 0.49 becomes 0, for example.

A chart is just a presentation of data. A remarkably useful one, as humans have a much easier time analyzing trends and patterns in a picture compared to a presentation based on a list of numbers.

Oh, by the way, to make your own inference you typically need contextual information (metadata). If the data is presented as numbers or as charts is of much less importance.

about 2 years ago

Supreme Court Hearing Case On Drug-Sniffing Dog "Fishing Expeditions"

pehrs Re:As good as lie detectors? (451 comments)

Congratulations, this must be one of the more ignorant comments I have seen on Slashdot in a long while.

Dogs have an almost insanely good sense of smell. For a dog to smell a bag of narcotics is about as hard as for you to smell if somebody opened a bottle of ammonia under your nose. The big problem is getting the smell out of your nose.

Training a drug sniffing (or any type of ID dog) involves teaching the dog first to identify a number of substances and then "mark" them. Marking is typically done either by the dog freezing and pointing with the nose, or sitting down. For a dog to be qualified you have a number of tests. Tests here involves the dog having to search 12 people, some of whom who may carry narcotics. Those not carrying narcotics get identical objects to hide on their persons. The handler, and the person holding the object, does not know if it is the real deal or not until after the test. If the dog misses a person, or marks the wrong person, it, and the handler, fails to qualify. And, yes, it's not unusual with a lineup where nobody carries anything.

A similar test often used is when a luggage band at an airport, where the dog must mark the specific bags containing explosives or narcotics. So the dogs and handlers certainly have to prove that they are able both to identify the substance and and that they know when it's not there.

Dogs are not infallible.They get tired, bored and exhausted just like their handlers. But it's not just a matter of a 'trained' officer having an 'opinion' about if the dog found something.

about 2 years ago

17th Century Microscope Book Is Now Freely Readable

pehrs Re:Hooke the pretender (116 comments)

Isaac Newton was a very good scientist, and an even better politician. Actually, "ruthless" would probably be the best term to describe the man. He spent years discrediting anybody who had crossed him, frequently postmortem. You see, Isaac lived for a long time, and took the liberty to spend the last few years of his life smearing people like Hooke and Halley.

There is a reason he was chosen to head the royal mint, where he ensured that some 30 coiners ended up hung, drawn and quartered in less than a year.

more than 2 years ago

US Presidential Debate #2 Tonight: Discuss Here

pehrs Re:Giving more people more money (706 comments)

Gaaa. So many wrong. So many wrong.

1. Small business are usually not very efficient. It's the medium-large size companies that get the benefits of scale. An economy dominated by small business can not develop. See, for example, the department store mess in India.

2. No, increased personal risk does not promote the creation of small companies, Actually, I would argue the exact opposite. When somebody says that it is too risky to start a business it means that your social safety system is not strong enough. In a country with strong social security an entrepreneur can take risks and try starting a business without risking things like health-insurance. See, for example, the high rate of successful small companies in countries with exceptionally high taxes and strong social security like the Nordic countries.

3. No, a bank will NEVER lend money to a person wishing to start a new company unless he has a good collateral. And if he has a good collateral they don't really care what he does with the money. Large loans "on your good name" is a thing that vanished about 100 years ago. An investor might invest money in a fledgling company, but they will at the very least demand equity. See, for example, any textbook in basic economy.

4. Considering your last point, why don't you argue for lower taxes on employment, and higher taxes on corporate gains? You know that the vast majority of the earning from small business are paid out as salary and not as dividend, right?

more than 2 years ago



Deepwater Horizon rig Accident Report is online

pehrs pehrs writes  |  more than 4 years ago

pehrs (690959) writes "The full accident report from the blowout at Deepwater Horizon is online, including an executive summary in video format and a huge amount of technical details. The report does not assign blame, but does list 8 major barriers that were breached, causing the accident."
Link to Original Source

pehrs pehrs writes  |  more than 7 years ago

Avalanche writes "Allegiance, released 2000, was a grand experiment created by Microsoft research in a try to get into the pay-per-month online market. After a long and rough road the project was abandoned 2002 and ended up open source in 2004. A group of developers has been working on the project ever since and a few days back the development team released the latest version, R3, including a new network code allowing play from behind NAT. The game and source code are freely available to those interested in playing or tinkering. Sadly the game uses DirectX and .net (for cheat prevention in online games), so it's not developed under Linux. (FYI: I am a developer of FAZ)"


pehrs has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?