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Comment Re:Until... (Score 2) 428

The video test shows the weight hitting dead center, making a clear mark- probably a crack in the tile. In addition, the tile was not held down- it was allowed to bounce up, releasing some of the energy- it wasn't a test representative of reality.. Affixed to the roof, the energy of the dropping object has to go somewhere. Furthermore, in a hailstorm- the hail will be hitting *everywhere* on the tile, not just in the center, but on the edges. I've been through a hailstorm with hail that was easily golf-ball sized. My roof (asphalt shngle) was a total loss, plus my cars all had major damage, including having to replace windshields.

All that said, I like the idea, and if Tesla is willing to warranty it against hail, I'll sign up./p?

Comment PDF Plugin? (Score 4, Insightful) 113

The PDF plugin is the worst part of Chrome, on every new install I have to remember what I did before to disable it before. I look at a lot of datasheets, and the built-in-viewer really sucks for doing anything but scanning to see if you want to search through your downloads directory to open it up in a read PDF viewer.

Comment Cannot stand alone (Score 1) 143

What bothers me about "personalized" learning is that at some point, these people will need to interact with others, so there must be commonality. Being able to communicate and share ideas is absolutely vital- and the language behind the ideas and how they are represented are a vital aspect of the idea itself. Personalization may help an individual, but it can hurt in the collective sense, where the people must work with the ideas of others.

Comment #1- It's not "Sharing" (Score 4, Insightful) 260

I think the idea of Uber & Lyft are great- but I really wish they would stop calling it "Ride Sharing" as it totally misrepresents what it is. It's selling! Sharing implies "I was going in the same direction, and I could give you a ride, and I'll split the cost with you." Of course this is what Uber and Lyft want people to think they do.

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.

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