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Comment Re:Albedo (Score 1) 386

Tropical storms in the Atlantic are strongly affected by the weather in the Sahara- it's part of the modeling they use to determine what the hurricane season will be like. It is worrisome because we don't know what it will do- it could make the hurricanes bigger or smaller, more or less frequent- the big issue is we don't know. I can't see how a big shift in the albedo *won't* change things.

Comment Re:Oh, stop spreading Apple's FUD, what a pile of (Score 1) 401

It is hard to design USB well, particularly with respect to power: a *huge* thing is making sure it's safe- Lithium batteries are dangerous when charged wrong, and if there is a fire, the lawyers will be after everyone they can possibly name in the suit. Remember that the lithium battery is very energy-dense- a lot of energy in a small space means the potential for a lot of heat in a small space.

All computers have some method of limiting the current out of their USB ports- if they don't, they can't get a USB Logo. During enumeration, a device requests more current, and the computer keeps track of the current available. If the current isn't available, enumeration fails. If a device draws too much current, the computer can crash, as it will drag the computer's 5V rail down. Most computers have current limiting in the form of a NTC resistor that will limit current but only after it heats up, so there is a delay, so short term overcurrents that aren't long enough to heat up the NTC resistor are dangerous. USB relies on the devices following the spec. If you violate the spec, you fail to get USB logo- and many of the big OEMs require logoed devices.

There are many USB hubs that can natively support more than 4 ports: Microchip's USB2517 is one (of many) I'm familiar with.

The 100W devices are coming as part of the USB C Connector, but with all that additional power, you better believe that the computer manufacturers are going to be careful as there is a much bigger chance of fire. To even get 100W, you have to have an active cable that identifies itself to the system as one that can handle the increased power. And Apple is very involved in USB type C development.

Comment Re:standarizing phone chargers (Score 1) 401

Apple is big into type-C. Using the D+/D- to signal what current/voltage to deliver is risky, as a mistake can blow up the phone and it plays hell with the signal integrity- these lines are for data.

The big things that type-C allow are: 1) up to 100W power, source and sink, 2) widely re-assignable signal paths. The spec allows for devices to both supply current and to consume current over the same connector. To get to 100W, the devices have to negotiate what kind of power to supply (voltage/current). The spec defines the communication to determine this- it doesn't happen over the USB connection, as the information has to be available before the USB connection is established (such as if the device is completely unpowered/dead battery). You also have to be able to tell if the cable is rated to support the power requested- you don't want the cable getting too hot and catching fire. Since the data pathways are re-assignable, you also have to know if the cable can support the signalling you want.

I think that Apple is big into type C as it follows with their simplicity/aesthetic. One connector is all you need for power/data/video- and that's not something you can do with lightning.

Comment Re:How about the FCC just does its job? (Score 2) 173

They do investigate, but investigations take expensive equipment out into the field and are extremely time consuming. The certifications are there to reduce the chance that an interfering piece of gear gets out on the market. The question is, where would the money for these investigations come from? The requirements today are mostly about paperwork and a few measurements on sample devices. For a commercial device, it's pretty effective- but the airwaves are a shared resource and we need a mechanism to prevent "the tragedy of the commons" type scenario. I'm not sure what is the best method, but I think that Bruce has a good idea.

Comment Re:Dell (Score 1) 237

I got mine as a refurb from woot so I didn't have the option- but the microsoft tax is not all that big relative to the cost of the laptop, I think that you might save $50- if you're buying a $2000 laptop, that may be in the noise. I decided that there are some times that I may need windows (sometimes you can't get around it), so I decided to get another mSATA drive, and I'll just swap the whole drive when I need to go Microsoft.

I do like it- especially the screen- it's beautiful. I tried an XPS13- the combination of limited memory (8G, soldered down, so not expandable) and a 13" UHD screen made it not as desirable. Still beautiful, but there are enough programs out there that do not scale text size, It is a 13" laptop and a 13" screen, especially for development, it is still awfully small. The precision also has a more USB ports- while thicker and heavier, it is still a better option for development.

Comment Re:Dell (Score 1) 237

I've got one- one of the few laptops I could find that had the capability of 16G and the UHD display. Ubuntu 15.04 installed fine, but I did have to do some fiddling to get the Wifi going. Still haven't gotten bluetooth working right. Doesn't have a built-in wired ethernet port- which can make things a pain. Definitely has issues with sleep/suspend- sometimes it wakes up, sometimes not, often it starts, but the Wifi chooses not to start.

Comment Re:Its all in the taxes and incentives. (Score 1) 211

The OP actually did specifically refer to the damage to the 'bulk electric system' which I believe was referring to the grid. No matter. A serious frequency/phase excursion can FUBAR the grid. If you FUBAR the grid of a modern country,that country is pretty much instantly moved to 3rd world status, particularly if the equipment needed to manufacture the necessary parts to repair the system are themselves powered by the grid. Big transformers are not a part that is kept on the shelf in a ready to install state, at least not in any volume. Even in small scale incidents, repairs are costly and time consuming.

Comment Re:Its all in the taxes and incentives. (Score 1) 211

You're right if you're considering just the end-users, but absolutely, incredibly wrong when you consider the entire grid. When different portions of the grid are out of phase, they start fighting each other- look at it in terms of just Ohms law- when all the voltages are exactly in phase, the difference in voltage between the generators is zero- so because V=I*R, the current between the generators is zero. Add a little bit of phase difference, the instantaneous voltage difference is no longer zero, so current will flow between the generators, since by the nature of a power grid, the R factor is very, very, very low, you can get an enormous current with a small difference. Most power generation facilities are only designed to source power, not sink (absorb) it- but that power has to go somewhere. If your equipment is fast enough, fuses, breakers blow. If not fast enough or it just comes on too fast, all that energy gets shoved into pieces of the infrastructure like wires and transformers, and when the energy gets added to the system faster than it can be taken away BOOM , the catastrophic damage happens. And the things that blow up are not things that can be replaced easily- big transformers can take months to years between order and delivery. If a single event destroys a lot of the infrastructure, it could be years before the grid is restored.

So yeah, it can be catastrophic.

Comment Not about security- it's shifting liability to you (Score 1) 148

With all the password hacks/cracks/thefts, my cynicism has led me to believe that password policies are not about protecting the user, they are about protecting the company. With every damn website and store loyalty program asking you to create an account, it's to the point of absurdity. But they tell you that you need to create a unique password, of course. The uniqueness is not there to protect the user, it's to protect the company from liability when their crappy data policies (storing passwords in plain text in a file protected by changing the robots.txt rules, etc) lead to a data breach. "Oh, the password that was stolen from our yahoo storefront for customized puppy faced iphone cases, and allowed Elbonian hackers to drain your bank account and charge child porn to your credit card? We told you not to reuse passwords- it isn't our fault you're now a felon on a sexual predator list."

Comment Often happens with small planes (Score 1) 373

As stated elsewhere, weight and balance are important in a plane, and accidents have happened as a result. I've taken a number of small plane commuter flights in the US and they regularly asked how much I weighed, and they definitely weighed my baggage. The smaller the plane is, the more it matters.

Safety is one aspect, efficiency is another- knowing how much you weigh also tells the airline how much fuel they must put on board, and even how much cargo they can safely take- much cargo flies on a space (weight) available basis.

Hell yeah, I want them to know how much weight is on the plane.

Comment Jamming... (Score 1) 97

Because this requires jamming the original signal, this is detectable, otherwise, it is MITM. Jamming is typically very easy- you just have to generate enough energy to overcome the incoming signal- the difficult part is being able to intercept the signal in the presence of your own noise. There are ways to cancel out the noise (like noise cancellation headphones)- but it is a really hard problem, even if you know the exact "noise" you're putting out.

This may push us faster into better types of keys, such as keys with 2-way radios, or even get us out of keys altogether, incorporating the key into one of the other devices we may have on us. We haven't had those keys commonly because of the expense of the technology- technology will progress, and so will the hacks.

Submission + - Remote exploit on a production vehicle to be presented at BlackHat (

Matt_Bennett writes: A scary remote exploit is going to be published that enables someone connected to the the same wireless (mobile data) network to take over many systems, including braking. This is an exploit in Chrysler's Uconnect system. Charlie Miller and Chris Valasek also demonstrated exploits in 2013 that could be done via a direct connection to the system, but this is vastly expanded in scope.

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