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Comment: Re:Subject bait (Score 1) 379

by pehrs (#47441397) Attached to: A Skeptical View of Israel's Iron Dome Rocket Defense System

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.

Comment: Re:Bullying (Score 5, Interesting) 183

by pehrs (#46591361) Attached to: Xbox One Reputation System Penalizes Gamers Who Behave Badly
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...

Comment: Re:victimless crime (Score 3, Insightful) 205

by pehrs (#46396127) Attached to: Child Porn Arrest For Cameron Aide Who Helped Plan UK Net Filters
<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.

Comment: Re:No need for cameras. (Score 1) 732

by pehrs (#44738363) Attached to: EU Proposes To Fit Cars With Speed Limiters
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 ;)

Comment: Management consulting... (Score 4, Informative) 331

by pehrs (#43959917) Attached to: Ask Slashdot: How Do You Prove an IT Manager Is Incompetent?
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.

Comment: Re:Wetware Controller advantages (Score 4, Insightful) 54

by pehrs (#43697377) Attached to: Astronauts Fix Phantom Space Station Ammonia Leak
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.

Comment: Re:Epitath (Score 4, Insightful) 184

by pehrs (#43323097) Attached to: A Sea Story: the Wreck of the Replica HMS Bounty
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.

Comment: Re:The reporter does not like electric vehicles (Score 4, Informative) 609

by pehrs (#42907561) Attached to: NY Times' Broder Responds To Tesla's Elon Musk
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.

Comment: Re:As good as lie detectors? (Score 5, Insightful) 451

by pehrs (#41828785) Attached to: Supreme Court Hearing Case On Drug-Sniffing Dog "Fishing Expeditions"
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.

Comment: Re:Hooke the pretender (Score 3, Insightful) 116

by pehrs (#41740315) Attached to: 17th Century Microscope Book Is Now Freely Readable
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.

Comment: Re:Giving more people more money (Score 1) 706

by pehrs (#41679705) Attached to: US Presidential Debate #2 Tonight: Discuss Here
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?

Comment: Re:If it ain't broke (Score 1) 141

by pehrs (#41372463) Attached to: Microsoft Wants To Nix Data Center Backup Generators
Having worked at a small high-availability data center I can assure you that AT&T does it right. Just starting the generators is not enough. You must also test your UPS systems, line sensing equipment and the long and complex line of electrical equipment that must work if you are to get a clean handover from the power grid over UPS to generator. Finding a failure in the chain is not nearly as painful when you can fall back to grid power while troubleshooting.

One of the more sneaky things to do to a facility is to walk into the transformer and kill off one or two phases, but leave the rest live. If their line sensing equipment does not work correctly (or the relay to cut out the power grid fails under load) the effect can be spectacular, and expensive. This is a classic problem not caught by just starting up the generators once a week.

Comment: In other forums... (Score 0) 306

by pehrs (#40664123) Attached to: SQL Vs. NoSQL: Which Is Better?
<rant mode>
I had a look in the other forums I frequent, to look around for similar questions. And look what I found:

In the construction forum:
Screwdriver vs Hammer: Which is better?

In the art forum:
Pencil vs Pen: Which is better?

In the transportation forum:
Walk vs Drive: Which is better?

In the pets forum:
Cat vs Dog: Which is better?

In the energy forum:
Wind vs Hydro: Which is better?

And guess what? They all came to the same conclusion. "It depends".

Can we now stop posting "SQL vs NoSQL: Which is better?" stories like this one, as they are utterly pointless?

For the article to be useful the author needs to chose and describe use cases that actually matters to the reader. "Better" is not a use case, and I really hope people don't pick the backend for their application based on how easy it is to implement a few tiny examples in C# or Node.js which is the only thing resembling a use case in that mess of an article.
</rant mode>

Comment: Re:Bunk. (Score 1) 709

by pehrs (#40437205) Attached to: Fires Sparked By Utah Target Shooters Prompt Evacuations
...only in America...

Let me tell you how it works in the old world...

Modern assault/battle rifles makes a bad choice for a hunting rifle in my experience. To list a few reasons:
* Innate accuracy is horrible
* Many are chambered for calibers unsuitable for big game (why hunt deer with .223 Remington when there are so much better choices?)
* Stocking, balance and design are not suitable for typical hunting scenarios.
* Sensitive to dust and dirt.
* You very rarely need more than one shot to down your game. (And when you do, you have time to chamber a new round before you realize that it's needed)

Anybody showing up with a military style rifle to a hunt where I hunt would meet a contempt that is hard to imagine. Semi-automatic rifles designed for hunting are grudgingly accepted. We do not wage war on our game, and we do not need military equipment.

No amount of genius can overcome a preoccupation with detail.