×

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

How a 'Seismic Cloak' Could Slow Down an Earthquake

ShooterNeo From reading the actual article, this could work (101 comments)

The primary problem with this concept is that you have to know very precisely the composition of the ground where you install this barrier. Another problem is that environmental changes - soil moisture, temperature, are going to affect the material properties somewhat (but maybe not enough to matter).

Essentially, extremely low frequency waves that trash buildings don't perceive the ground as atomic, the waves act over their wavelength, which is very long, and so if you put things into the ground, it changes the material properties. Carefully drilled holes apparently can change the properties in dramatic ways. The word "cloak" is sexy, but the more interesting bit mentioned at the end of the paper was the prospect of building a bandstop damper with the low corner at 0 Hz.

It doesn't do you much good if your earthquake prevention device reflects the energy somewhere else dependent on the epicenter, and it also doesn't do you much good if it doesn't block enough frequencies to stop it from trashing your buildings. A bandstop filter would operate over a broad enough band to attenuate all the frequencies, and it wouldn't reflect energy to other buildings (which could have obvious liability concerns.) Imagine a plaintiff's attorney showing a standing wave pattern of destruction emanating from a field of holes drilled by the defendant's firm.

The other satisfying nature of this tech is that it's proactive. Instead of building structures that will probably collapse if a magnitude 8 happens anyway, you go out there and build armor that will stop the earthquake entirely. Also, a field of holes and concrete and various pertubations, all buried, is a lot less ugly than the structural changes needed to reinforce a building against a major earthquake.

It would be expensive to do the detailed surveys and compute the solution, but it would create more high education jobs, and it's probably worth doing.

about 8 months ago
top

Astronauts' Hearts Change Shape In Space

ShooterNeo Re:Spinning Space stations (113 comments)

Was the pod powered up with it's instruments online? A pod like that would have a reaction control system and automated avionics.

about 8 months ago
top

Linux May Succeed Windows XP As OS of Choice For ATMs

ShooterNeo Re:How I've been taught to do it (367 comments)

You feel this solution is a kludge? How should it be done? The way I see it is it provides a nice neat system of separate, extremely reliable and simplified subsystems that are as independent of each other and as simple as they can possibly be.

User Interface layer - instead of running a huge, complex, and memory and power hungry windows OS, you are running a newer OS that is really a flavor of Linux with a bunch of fancy libraries for fancy graphics and multitouch and other features added on.

Communication and transaction layer - instead of running it on the same computer that does the UI (creating the possibility that someone can corrupt the much more complex UI layer and cause it to give them free money), you do all the transactions on a much simpler computer, running well documented (and fully sourced) code and nothing else.

Hardware control layer - instead of doing this on the same computer doing the above, you give each one a dedicated (but extremely tiny and simple) computer for each task.

about 8 months ago
top

Linux May Succeed Windows XP As OS of Choice For ATMs

ShooterNeo How I've been taught to do it (367 comments)

Finishing my computer engineering degree this semester. The way I've been taught how to implement a system like this is the following :

1. The outermost "user land" control panel should use an OS that is both lightweight, will work on a lot of hardware (so you can switch hardware if during the production of the ATM a vendor goes out of business), and offers a lot of graphical libraries for a pretty interface. Android sounds ideal for this.

2. The android display would communicate via network (probably TCP/IP) with a small server running an embedded flavor of Linux. This server would be stripped down to the minimum features and services, running on a tiny little ARM architecture chip. It would be the computer that actually talks to the bank via encrypted link and controls the cash dispensing process.

3. For the actual physical interlocks and running the motors to dispense the cash, you'd communicate via a serial bus with several small microcontrollers or PLL controllers. Each would be running a very simple program written in C (or ladder logic tree) to do their jobs, which would be to do the actual dispensing and monitoring all the various switches and so forth.

The point of this hierarchy (rather than using one computer to do everything directly) is to compartmentalize the design, allowing you to debug it more easily and also improving security. Someone compromises the outer control panel - they won't be able to dispense cash.

about 8 months ago
top

Study Finds Methane Leaks Negate Benefits of Natural Gas-Powered Vehicles

ShooterNeo Re:Media picks up minor detail to play gotcha! (102 comments)

Strictly speaking, if you wanted to go to an all-methane economy, you could do it. Planes, trains, and trucks would all be fueled using liquid methane. It's cold and harder to handle than diesel/kerosene, but it's doable.

The reason you would make the switch is because you can create methane synthetically via electrolysis and Sabatier reaction. The ultimate energy source would be solar or nuclear.

about 9 months ago
top

Star Trek Economics

ShooterNeo Basic Economics (888 comments)

The problem is simple, right out of the first chapter of a high school economics class. "wants" are infinite. Consider our daily lives in today's world. The "working poor" among us live lives right around the "poverty line". Yet they can generally afford motor vehicle transportation (even if it's the bus), to spend most of their time in air conditioned environments (even if it's the workplace at McDonalds), can call anyone on the planet in theory (even if it's from VoIP at a library), and so on. Even the shittiest life is the life of a king a thousand years ago.

Please note that I am not trying to justify social darwinism : I do think something is rotten in our society that causes all income gains to be accrued by the rich and NONE of them go to the middle/lower class.

If we have star trek grade technology, it merely means that the pie is a lot bigger. With Star Trek grade tech, presumably we can tap into the resources of entire stars and planets and manufacture almost anything with minimal effort. But people's desires for a slice of the pie have grown proportionally. Perhaps an impoverished person in Star Trek can get limitless food, basic medical care, and virtual reality porn. But he can't afford his own starship or planet or any of the other toys of the mega-rich. And can you imagine how expensive having a kid would be in such a world?

about 9 months ago
top

EU Considering Sensors In Sewers To Detect Bomb-Makers

ShooterNeo Re:That old business partner I want to get back at (219 comments)

Don't forget to pour some fuel oil down the drain as a chaser.

You know, technically, you haven't committed any crime when you do that, have you. You didn't actually make any explosives, but it seems like if these sensors even worked at all, they would alert to this combination.

1 year,25 days
top

Google: Our Robot Cars Are Better Drivers Than You

ShooterNeo Re:At what speed? (722 comments)

Well, there's one other factor you haven't thought of, apparently. More high school physics here. What happens if the cars, separated by 1 meter, DO collide.

With the distance so narrow, the relative velocity between the vehicles cannot become very high. (because the distance for acceleration is only 1 meter) The collision should do minimal damage, and then the collided 2-vehicle system should still keep decelerating because both vehicles still have brakes.

That's the theory, but I acknowledge that at highway speeds, it may not work out this cleanly.

about a year ago
top

Google: Our Robot Cars Are Better Drivers Than You

ShooterNeo Re:At what speed? (722 comments)

This isn't how the math works. If the vehicle in front of you is applying maximum braking force, you can see it immediately - even if their rear bumper has moved on a few centimeters.

As for wireless communications : think of all the problems this introduces, versus having each car use their own sensor packages.

I'm not completely averse to the wireless idea, but I think the system should be designed to work reliably if wireless is jammed or hacked. It would not be difficult for someone to make a "troll lol lol stop" gadget that they could use to shutdown traffic at will if wireless worked the way you want it to.

about a year ago
top

Google: Our Robot Cars Are Better Drivers Than You

ShooterNeo Re:At what speed? (722 comments)

The first car cannot avoid the deer, true, but this condition will not cause a pileup.

Think about the physics. The inelastic collision between the deer and the car will marginally slow the front car down, true, but only slightly. (since a car weighs 2000 kgs and a deer weighs less than 100, for an estimate). So the combined car-deer vehicle will be going only slightly slower.

Ok, so now the car that is about to hit the deer applies maximum braking force. It begins to decelerate at a rate limited by friction between ground and car. This friction is independent of the mass of the car, for reasons I can't fit into here.

The moment it hits the brakes, the car behind it will see the distance between the two begin to decrease. They are "bumper to bumper", or within 1 meter of each other. The car behind will apply maximum braking force the very moment a single cycle of it's control loop happens (probably 1/1000 or a second or so).

The car behind that will do the same, and so on.

As long as no car in the pack has significantly better brakes than the other cars, no one will hit anyone. Even if a particular car does have better brakes, the collision will only do slight damage, as the relative velocities will be low.

Contrast this to what can happen in a real highway, where a car in front can have time to decelerate to a stop in some cases, and the cars behind may be driven by a distracted driver who does not see the stopped vehicle in time. The collision happens at highway speeds between the trailing car and the stopped car. This, in some cases, will be fatal.

about a year ago
top

US Executions Threaten Supply of Anaesthetic Used For Surgical Procedures

ShooterNeo Re:Nitrogen (1160 comments)

The breathing rate from hypoxic drive is slow.

about a year ago
top

4K Ultra HD Likely To Repeat the Failure of 3D Television

ShooterNeo Problem is, most content struggles to do 1080p (559 comments)

As it is right now, the only true 1080p content is high bitrate blu-ray disks, and PC games. There is nothing else.

None of the currently released consoles can render 1920x1080 at 60 fps : they use a lower frame rate (30 fps) and a lower rendering resolution (not even 720p internally for most games). The next gen can maybe do it, but I suspect that some games will use lower frame rates or internal resolutions so that they can put more detail into other things.

Broadcast channels, satellite channels, and HD cable channels all generally are full of lower bit-rate tradeoffs. You need about 30-50 mbps to do 1080p without compromises or visible encoding errors.

Maybe in another 10 years, when the technology is actually fully utilizing the 1080p displays we already have, will an upgrade make sense.

Note that this is for video content. For your computer or tablet PC, higher resolutions are useful, and shipping tablets are already at higher resolutions.

about a year ago
top

Barbarians At the Gateways

ShooterNeo Uh (321 comments)

Isn't HFT just insider trading?

Insider trading = making stock trades using information that has not yet been disseminated to the open market.

HFT trading = using mathematical algorithms to detect the reaction of the open market to information, and to get ahead of it to make advantageous trades before the entire market can react.

about a year ago
top

British NHS May Soon No Longer Offer Free Care

ShooterNeo Re:My spider sense in tingling.... (634 comments)

Drug dealers are a classic example of what commerce looks like without government to protect from cheats....

Since drug dealers don't have government level resources, they can't imprison the cheats. They have only a few options : demand immediate monetary compensation, physical harm, or murder.

about a year ago
top

The Reporter's Fifth Amendment Paradox

ShooterNeo Re:Because we know? (452 comments)

Alice can say that all she wishes, but the judge will look at the signed immunity agreement and if he finds it to be adequate, will order Alice to the witness stand. (Alice's attorneys can of course delay things by objecting to the terms of the immunity agreement, but eventually it will be to the satisfaction of the judge)

If Alices refuses to spill, the judge then finds her in contempt and will jail her until she cries uncle, or about 10-15 years passes.

about a year ago
top

The Reporter's Fifth Amendment Paradox

ShooterNeo Re:Because we know? (452 comments)

In this case, Alice is offered a signed immunity agreement if she testifies, exempting her from prosecution for any information she reveals on the witness stand.

After she is given immunity, she may no longer take the 5th as on paper there is no way she can be prosecuted.

about a year ago
top

US Forces Ready To Strike Syria If Ordered

ShooterNeo Won't the Syrians be able to get ready? (918 comments)

If the Syrian leadership knows that there's basically a 100% chance of a huge volley of missiles hitting them within a week, hasn't everyone already left and gone for cover?

Couldn't they fill the presidential palace or wherever their senior leadership is with rebel prisoners, just to knock out 2 birds with one stone?

about a year ago
top

How To Monitor Leaky Radioactive Water Tanks

ShooterNeo Re:Solar Perhaps (111 comments)

it's on top of it

about a year ago
top

How To Monitor Leaky Radioactive Water Tanks

ShooterNeo Solar Perhaps (111 comments)

The only thing it's missing is a small solar panel to keep the battery charged. That way, no one has to climb those tanks of deadly radioactive water unless hardware has actually failed. Some of those Arduino boards already have battery chargers on them, but if not, a small regulated LiPo or NiCad battery charger is what you need. Then you just need a solar panel that is small and has the right output voltage. Sunelec.com seems to sell a 10 watt, 12 volt panel for $15. No big deal, and that's more than enough juice. Size the panel right, and you can do the monitoring continuously for a measurement every minute or so. (not that this really matters, but why not overdeliver?)

about a year ago

Submissions

top

Watson Pwns the best players in Jeopardy

ShooterNeo ShooterNeo writes  |  more than 3 years ago

ShooterNeo (555040) writes "Watson takes the competition to the cleaners this round. The elegant part about it is that IBM has 'solved' the Jeopardy problem. As long as they save the software for this machine, they can win any Jeopardy match given anytime, anywhere.

What use is Watson? IBM hopes the same technology will be able to analyze patient medical files and pattern match with vast storehouses of medical information. The main reason objection to Nurse Practioners acting as primary care physicians is that they lack the education and experience to identify less common illnesses.

The most accurate method today for diagnosing a heart attack is not a top cardiologist but instead a static mathematical formula based on key syptoms. Sophisticated learning alogorithms on a supercomputer would be far superior to this, and would make possible for health care providers everywhere to diagnose patients correctly."

Link to Original Source
top

Dutch pair tows rocket with private submarine

ShooterNeo ShooterNeo writes  |  more than 4 years ago

ShooterNeo (555040) writes "So these Dutch blokes are about to test out their hand built sub-orbital rocket that they are towing to the launch site using a private submarine they also built. I don't even know what to say about the pure epicness of that. Shame these aren't the kids of a billionaire, can't even imagine what they could do then."
Link to Original Source
top

The Fundamental Design Fault of Windows Vista

ShooterNeo ShooterNeo writes  |  more than 6 years ago

ShooterNeo (555040) writes "In their haste to clone features from Apple, and to add new useless features to lure in users, Microsoft forgot why their operating system has economic value in the first place.

First, the delays. There is no technical reason why an operating system cannot respond essentially instantaneously to user input on any computer hardware newer than 2000. It is feasible, using vector graphics, to make control panels, menus, file directories, and other common tasks respond to user input in under 100 milliseconds. An operating system designed for productivity would do this.

Second, Windows has always been valuble because of backwards compatibility. Choosing to mostly give up this goal in Vista destroys the value of windows. Microsoft should support backwards compatibility for any application ever created. A virtual machine that uses a copy of the actual version of windows or DOS the application was written for would make this goal feasible.

User Access Control is yet another collosal blunder. Microsoft should have used virtualization to maintain backwards compatibility and to prevent malicious applications from causing real damage.

Discuss"

Journals

ShooterNeo has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?