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Did Russia Trick Snowden Into Going To Moscow?

Cassini2 Re:Plot Twist (346 comments)

What kind of intelligence agency traps an agent in Moscow?

It is possible Snowden is working for the CIA. Either the American's are really dumb, trapping him in Moscow, or they are smart and deliberate.

about 2 months ago
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Solar Roadways Project Beats $1M Goal, Should Enter Production

Cassini2 Thermodynamically Impossible (311 comments)

Isn't it impossible for solar cells to melt significant snow?

The black road surface will effectively capture almost all of the sun's energy. In the northern U.S. and Canada, roads routinely get covered in snow.

The solar cell can capture a portion of the sun's incoming energy, and potentially use it to power heaters to melt the snow. This approach has several problems. Firstly, the solar cells / heater mechanism is less energy efficient than a black road surface. Secondly, if the snow falls when it is dark, the solar cell will stop working (unless it has some big batteries are present, and even they won't last long in a heavy snow fall.) Lastly, the best sun occurs in the summer, and the snow hits in the winter, when less solar energy is available.

About the only way a solar cell can keep up with incoming snow is if the solar array is much larger than the area of snow being melted. However, even then, you still have the problem of the solar array getting covered in snow ...

about 2 months ago
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UPS Denies Helping the NSA 'Interdict' Packages

Cassini2 Re:No need for UPS to help (207 comments)

They also have custom's warehouses for out-going goods. On the U.S.-Canada border, there are warehouses for goods going in both directions. US bound goods get Canadian warehouses, and Canadian bound goods get Canadian warehouses. Both are easily accessed by persons with the right American security credentials. Treaties, special agreements, and informal arrangements are all up-and-working.

Times have changed. Canada is closely aligned with U.S. security policy. During the Vietnam war, draft-dodgers claimed refugee status in Canada. Starting with the new conflicts, fleeing soldiers are sent back as deserters.

about 2 months ago
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UPS Denies Helping the NSA 'Interdict' Packages

Cassini2 Re:No need for UPS to help (207 comments)

Many (all?) custom's warehouses are operated by third-party companies. This will be a little bit more complicated than inspecting luggage. However, the companies (subsidiaries) that operate those warehouses get their entire revenue from allowing people to transport goods across borders. I suspect the NSA can get away with almost anything in that environment.

about 2 months ago
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The Mere Promise of Google Fiber Sends Rivals Scrambling

Cassini2 Re:Making sure Google Fiber isn't profitable (258 comments)

Monopoly playbook 101: protect your monopoly. Cut prices anywhere there is competition, simply to discourage/bankrupt the competition.

about 3 months ago
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NASA, France Skeptical of SpaceX Reusable Rocket Project

Cassini2 Risk Statistics (333 comments)

In the case of NASA, people were on-board for every shuttle launch, and each launch cost billions. The satellite payload could cost over $400 million each. If a $15,000 dollar component has a 1 in 10,000 chance of scuttling a launch, it was easy to justify fixing it. The space shuttle had many subsystems, and each and every subsystem was built from from many small individual components. Thus, NASA rebuilt, checked or replaced everything on the entire shuttle on every launch.

I don't think SpaceX is going after the same market. For human rated launches, ISS resupply missions, or expensive satellites, they can sell brand new rockets. For inexpensive payloads, it could pay to roll the dice. SpaceX rockets are designed to be much less expensive than the competitions.

about 3 months ago
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Toyota Describes Combustion Engine That Generates Electricity Directly

Cassini2 Re:Efficiency? (234 comments)

The issue is weight. In a car, weight is an issue. A mechanical gear box is a very light method of adapting engine output for use at the wheels. Electricity cannot match the power/weight capabilities of a mechanical gear box.

On the other hand, a locomotive is a very different application. A train has a huge mass, and the electric generator/motor approach does not add significantly to the total weight of the train. Also, huge advantages exist in the electric generator/motor approach on a locomotive. The diesel engine can be operated at optimal fuel economy. It is possible to apply the maximum torque to the locomotive drive wheels while avoiding wheel slip. When accelerating very large masses, following the optimal acceleration curve is a big advantage. Also, a safety issue exists in trains where wheel failure (and hence derailment) can occur if excessive wheel-slip occurs. Hence a constant traction drive on a locomotive has benefits.

about 3 months ago
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WRT54G Successor Falls Flat On Promises

Cassini2 openWRT runs, without wireless (113 comments)

I agree with Andrew Johnson. Almost everyone will want a wireless router. A Linux, open-source, router was the segment that the WRT54GL filled.

It's a bit of a shame. I need a bunch of new routers with wireless support and ideally cellular support too.

about 3 months ago
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Why Tesla Really Needs a Gigafactory

Cassini2 Re:Does the math work out? (193 comments)

GM and the other car makers do not make money on cars. These stats predate the collapse, but GM wasn't make any money manufacturing cars. GM was making money on financing. As such, GM didn't go broke until the banking crisis hit. Similarly, the auto dealers don't make money selling cars. They make money in add-ons and services (including repairs.) For instance, many dealers charge $200 dollars to transfer your ownership, over and above the charges at the DMV. These extra charges add up. I'm pretty sure the repair parts operation at a modern OEM makes far more than the original cars.

about 3 months ago
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Mathematical Proof That the Cosmos Could Have Formed Spontaneously From Nothing

Cassini2 Re:Mathematics is a language, not a science (612 comments)

As I recall, many aspects of modern physics fit into the "mathematically inconsistent" category. The equations - as written - are not consistent with one another. Additionally, the equations don't agree with our understanding of reality, and know one knows why. As a result, many mathematician's look at the stuff that happens in physics and engineering as somewhat dubious. Physicists also recognize this problem, and for them, an important theoretical challenge is to generate mathamatical frameworks that both describe reality and are internally consistent (which is hard).

One of my mentors, a statistician, pointed out that if the mathematics yield useful predictions about the problem you are working on - then run with it. Almost all modern sceince and engineering is based on the "it yields effective predictions, therefore we use it" principle. I still find it odd that a statistician was the realist in the group ...

about 4 months ago
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French, Chinese Satellite Images May Show Malaysian Jet Debris

Cassini2 Re:Normal situation (103 comments)

Yes. Lot's of stuff is floating around the ocean. It seems particularly unlikely that large pieces of aircraft fuselage are floating in the ocean, over two weeks after the plane went down, and after heavy storms. The satellite is probably finding wales, bits of long cap-sized ships, sea weed, parts of shipping containers lost at sea, etc. This is the third or fourth time in this search that the satellites have found objects at sea that have not come from MH370.

If they find smaller debris, like the parts of seats and life-preservers, then it is much more likely that they have found the aircraft crash site.

Another issue is that satellite bandwidth is expensive. I don't think the satellite providers bother to download surface scans of the Indian Ocean on a continuous basis. Thus, even if a satellite was in position to capture the crash, it is unlikely that it bothered to down-link the data.

about 4 months ago
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How Do You Backup 20TB of Data?

Cassini2 Re:Hmmm... (983 comments)

At 10 characters per second, the backup would take 63,419 years(*) and require 659 TJ or 0.2 TWh of power to complete. I have a customer that still uses paper tape. It lasts and lasts, and I have only replaced the reader once. The punch needs a new power supply every 20 years or so.

However, 63,419 years is a long time to wait for a backup to complete.

(*) this assumes that 1 TB = 1,000,000,000,000 bytes. It takes almost 70,000 years if you add the extra 10%.

about 5 months ago
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Google Blocking Asus's Android-Windows "Duet"?

Cassini2 Re:Google more restrictive than Microsoft (194 comments)

If Microsoft's PR shills are saying: "Microsoft's product sucks so bad in the marketplace that Google isn't letting companies release enough product to run alternative operating systems", then Microsoft needs new shills, better product and a new PR department.

about 5 months ago
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Free (Gratis) Version of Windows Could Be a Reality Soon

Cassini2 Re:Is Win 8.1 that bad? (392 comments)

The strange thing is: most users adapt to the programs they use, and the program becomes less annoying over time. Windows 8 appears to defy that rule. I hate Windows 8. I've been using it for 6 months now. I hated it at the beginning, and I hate it even more now. I simply cannot make Windows 8 do whatever it is I am trying to do.

A big problem is that Windows 8 does not work well with touch pads. Every other laptop, I use the touch pad. My Windows 8 laptop has a mouse at work, and a mouse at home.

about 4 months ago
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Stack Overflow Could Explain Toyota Vehicles' Unintended Acceleration

Cassini2 Re:Dangerous recursion! (664 comments)

When interrupt handlers are considered, it is very difficult to "stop at a certain level." I'm not aware of any processors that have a software stack, and check the the stack depth when responding to an interrupt in hardware. If hardware paging is present, some operating systems use guard pages to make software stack overflows detectable. However, many embedded systems do not have a hard disk, and as such, don't implement virtual memory and hardware paging.

In the small embedded processor market, the best you can hope for is a hardware stack (like some Microchip products use.) If the hardware stack overfills, then a hard reset occurs.

about 5 months ago
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Stack Overflow Could Explain Toyota Vehicles' Unintended Acceleration

Cassini2 Re:In Canada Engineers Are Required to Write the C (664 comments)

Almost all safety systems in Ontario have not been designed or written by a PEO licensed engineer. The PEO is the same organization that tried to get Microsoft to stop using the term "Microsoft Certified Systems Engineer (MCSE)" and largely lost. If you start analyzing real and deployed systems, you will be shocked at what you find.

Yes, there are a few very well designed machines out there that do hardware and software interlocks properly, and in an obviously safe fashion. These are the exception, and I am delighted to find the few exceptions that exist.

However, if you want excellent examples of obviously unsafe things, consider:

- The gas pumps at Shell, Esso, and Petro-Canada. How many brands have an Emergency Stop button? One?

- Toyota cars have a push to start button that is also a push and hold to stop button. So how do you stop the car quickly? Shouldn't a car that has push-button start, also have a push-button stop, that is a different button and works quickly? Why would Toyota follow the Microsoft standard of using a start button to stop, instead of following the very well thought out emergency stop button standards?

- Hospitals have implemented a number of computer systems that are networked, and make the job of nurses quicker, easier and more productive. This reduced nursing costs considerably, and fewer nurses are looking after more patients. However, these systems are not reliable, and the official backup plan is that a nurse will step in and do the job manually if the system fails. Unfortunately, many of these core systems are also running on Microsoft Windows (often Windows XP.) One virus, or one bad update, written by a non-engineer, to wipe out many core systems. A major hospital had its Internet linked systems disrupted because too many people watched Olympic hockey (over the critical internal network.) Has any engineer approved any of this? Does any hospital have enough nurses to cover off in the event of a computer failure?

- Most servo-motor drives are sold with a "not recommended that power be cut by an emergency stop/safety system" warning buried somewhere in the documentation. Ignoring this, and assume braking resistors are used, and power is really cut. Most motors will follow an exponential stopping curve, and appear to coast to a stop. A mechanical engineer doing a PSHSR (Pre-Start Health and Safety Review) will expect the machine to stop quickly, and not coast. The cheapest way to do that is to dynamically brake into braking resistor under full software and transistor control. The second cheapest way is to use a parking brake, but those are not rated for safety and only a fraction of the servo-motor market uses parking brakes anyway. How many PEO licensed mechanical engineers doing PSHSR reviews have passed systems with incorrect software E-STOP circuits and Safety Circuits, and failed E-STOP circuits and Safety Circuits that cut power to the motors in hardware?

Do not depend on the PEO and statutes to keep you safe ...

about 5 months ago
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Stack Overflow Could Explain Toyota Vehicles' Unintended Acceleration

Cassini2 Re:coding standards (664 comments)

Every computer science, computer engineering and software engineering major is taught the wonders of virtual memory and recursion. They are taught pointers are good, and global variables are bad. When writing embedded software, the engineers do as they have been trained ...

about 5 months ago
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Whatever Happened To the IPv4 Address Crisis?

Cassini2 Re:CGN, perhaps? (574 comments)

Wide and easy adoption of any new technology requires backward compatibility. IPv6 is not even slightly backwards compatible. If you have one IPv4 application on the entire network, then you pretty much have to keep IPv4. On the other hand, NAT and CGNAT will run the applications of the majority of users with absolutely no problems.

What I have never understood is: why has no one redesigned IPv6 in such a way as to be backwards compatible as possible with IPv4?

about 5 months ago
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Customer: Dell Denies Speaker Repair Under Warranty, Blames VLC

Cassini2 Re:Definitely Small Claims and/or BBB. (526 comments)

After doing the same demo a hundred times, I opened the screen of a brand new laptop to show a client. It cracked right before the client's eyes.

Asus replaced the screen on the laptop, with some difficulty, but they did replace it. Never underestimate the potential for a latent stress fracture.

about 6 months ago

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