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Comment: Re:Pimping LEDs (Score 1) 400

by minimum (#30280816) Attached to: Lifecycle Energy Costs of LED, CFL Bulbs Calculated
Yet LEDs don't really compete with CFLs yet. The article does mention that even a 60W incandescent equivalent is just experimental in LEDs, though CFLs have brightnesses at all levels even far past equivalence to 100W incandescents. Meanwhile, LEDs still generally aren't as efficient as their equivalent brightness CFLs. And LEDs' extra inefficiency puts heat into rooms that then require extra cooling, which consumes more energy.

Do you have any numbers to back your claims?
Considering only lightsource efficacy, LED's have passed CFL quite while ago: http://en.wikipedia.org/wiki/Luminous_efficacy

Comment: Re:bright, but spendy (Score 1) 225

by minimum (#27615495) Attached to: A Monster LED Array For Irresponsible Fun
What are you talking about?
The efficacy of halogen light is about 20lm/W, CFL around 50-70 lm/W
The LEDs, depending of drive current (and make/model) 70-100 lm/W

So there's no way the halogen and CFL are far better than LEDs.
In fact, the LEDs combined with special optics have the huge advantage over the halogen,CFL and high/low pressure sodium lamps because of the precicely controlled light pattern. Conventional luminaries have usually reflector, which directs the light about to right direction, with efficiency of 30-70% .
In streetlights with LEDs it would mean no "hotspots" under the streetlight pole but evenly distributed light where it's needed and no unwanted glare, light pollution and etc. The even distribution means less lumens needed from light source. What matters is the luminaire efficacy.

The 100W LED module from the original article is not very good for applications where the light distribution is crucial because there's no (good) optics for the large array of tightly packed emitters in one package. Similar situation as with gas discharge and fluorescent lamps where the light is not sourced from one point (LED die is usually around 1mm2 in size) but more like area. LEDs, such as Cree XR-E, XP-E and Philips Lumileds Rebel have huge selection of aftermarket optics available for different applications. The efficiency of the optics ranges usually around 80-95%.
Another matter is cooling of the LEDs. The 100W module definitely needs active cooling to dissipate the generated heat in order to maintain the die temperature below 70-80 degree in Celsius. Temperatures above that will damage the phosphorous coating and die which results in rapid degradation of light output.

The reddish light from high pressure lamps is not better for dark environments because of the spectrum. Human eye when adjusted to dark (scotopic vision) is most sensitive to 505nm light which is cyan. The photopic (daylight vision) peak sensitivity is 555nm (green).

+ - Intel hardware spying, even with power unplugged!

Submitted by
blucat2 writes "Check out this one. Intel are now shipping on-board tranceivers on "every piece of silicon that comes out of their factory", a direct quote from the CEO. So now, they can access your PC, modify the hard disk, retrieve information, even when the thing isn't turned on!! They call it AMT, and you can't remove it. You can check it out on Intel's site, there's a few pages and a PDF. Here's a few cut and pastes, as I usually do when I get amazed at how offensive what a company does is.

blucat AT optusnet.com.au

http://www.intel.com/technology/platform-technolog y/intel-amt/index.htm

Discover: Intel AMT stores hardware and software information in non-volatile memory. With built-in manageability, Intel AMT allows IT to discover the assets, even while PCs are powered off. With Intel AMT, remote consoles do not rely on local software agents, helping to avoid accidental data loss.

Heal: The built-in manageability of Intel AMT provides out-of-band management capabilities to allow IT to remotely heal systems after OS failures. Alerting and event logging help IT detect problems quickly to reduce downtime.

Out-of-Band system access Allows remote management of platforms REGARDLESS OF SYSTEM POWER OR OS STATE!


Non-volatile memory stores hardware and software information, so IT staff can discover assets even when end-user systems are powered off, using the OOB channel.

Intel AMT is a hardware- and firmware-based solution connected to the system's auxiliary power plane, providing IT administrators with "any platform state" access."

+ - Google censoring has started

Submitted by Anonymous Coward
An anonymous reader writes "Apparently Google has started censoring content to please the governments where they do business. According to a report from India, a politician pressurized Google to remove content which portrayed her in a bad light. Truth hurts."

To communicate is the beginning of understanding. -- AT&T