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In yellow, scattering light from the silicon nano-wire. The dimmer areas are coated with gold, reducing the scattering of light - hence cloaking.

There has been so many developments involving ‘cloaking devices’ over the past few years that I’m starting to wonder if the invisibility devices found on sci-fi shows like Star Trek are close to becoming a reality. With this in mind, an engineering teams from Stanford University and the University of Pennsylvania have recently announced their development of a ‘plasmonic cloaking’ device. The invisible machine detects light and is capable of ‘seeing without being seen.' Plasmons, in basic terms, are plasma-quasiparticles with the oscillation of free-electron density relative to the stationary positions of ions in metals (metal being the key word here) at different frequencies that scatter light. This plays a huge role in the optical properties in metals when it concerns light-waves. The engineers picked up on this principle and used it to develop their device using silicon-based nano-wires encased in a thin sheet of gold which dissipate light-waves by adjusting the ‘metal to silicon ratio’ (tuning the geometries). This makes the device invisible to the naked eye, and since there is no known picture of the ‘device’ (as it’s invisible) we’ll just have to take Stanford’s word for it (joking of course).

The engineering teams found that it was by precisely fine-tuning, the gold-plated nanowires that the scattered light cancelled each other out through the metal and semiconductor (destructive interference). They found that much of the visible light spectrum could be dissipated no matter what angle you viewed the device from and that using other metals, like copper and aluminum, work just as well as gold at making the device invisible. The only mitigating factor is making the ‘dipoles’ (separation of positive and negative ion charges) are lined-up precisely. Otherwise, the desired effect is lessened or even cancelled outright.

The teams state that this new technology could be applied to solar-cells (generating a tremendous amount of electricity through light dissipation), solid-state lighting and even digital cameras (improving image quality by reducing motion-blur associated with light). Those seem so mundane compared to ‘cloaking’ my vehicle while parked in a no-parking zone or making my home invisible to uninvited guests.

Cabe

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     It had been a busy weekend. On the Friday I'd been down to Mum's after work to pack some tiems away before the builders came. Saturday saw me off doing another of my weekend activities on Wensleydale Railway, where what I'd hoped to be a nice relaxing day saw track work at the crossing I was manning - so much for peace and quiet.

     On arriving home I found a couple of parts on my doorstep. Ah yes. Time to do a bit of repair work. My HF vertical had become poorly over the winter, it had gained rather a lopsided look. Plan A had been to sleeve where it was joined to the insulating section at the base, but when we took it into the workshop it was just two of the rivets that had loosened up. So these were drilled out and replaced. The feed point was doing most of the support work here, so we added another rivet here.

     Why not just bolt the thing together? Well unless you like to try to fit a nut and washer 12 inches inside a 2 1/2 diameter tube we didn't think there would be any point.

     Okay so what effect did it have? Well I landed 9A9RR on EU-136 with a 57 report despite me showing about a 2.5:1 SWR on 14.260MHz. Now the case was that the antenna had been tuned up at the digital portions of the bands (40, 20, 15 & 10) as that's my usual mode of working. So the conclusion is that it's now a lot happier, the bandwidth has dropped, possible as now the electrical connection between the feed and the element is somewhat better. There are tuned radials fitted, I've not adjusted them this time, and they are about 8 ft off the ground. This antenna is no longer made (EVX-4000) as it's required regular maintainance, plenty of silicone to stop water getting into the 20m trap and the plentiful use of self amalgamating tape where the tubes are jointed. I can't complain, I have 6 years use out of it so far and my squeeze a couple more out yet until I decide what to replace it with. My postage stamp garden suits this one, although when I lower it on the mast I haven't much room at the end of the garden to play with.

     Sunday was busy too - this time near Dent in Cumbria. To provide communications to the ambulance at the bottom of the hill at Lea Yeat, I was stationed not far from the summit of the Coal Road to Garsdale with my 6m/20ft portable mast and a talkthrough radio. In the end we only had messages relating to them arriving, setting up and finishing without incident, but they are in a hole radio wise.

     I haven't decided what to do with the temperamental 6m beam as yet. I will however give it another try before I think about getting rid and sorting a HB9CV for the band. I have one for 2m, it's been used portable, and got me into Southern England from home on the 20ft mast with 30W on SSB.

At present, the LED Power Supply used as garden lights, tunnel lights, and indoor places used in commercial lighting, office lighting, etc. are highly desirable. With the advances in LED technology, lower prices at the same time, the phosphor price increases and cost pressures on the traditional lighting, these provide a good opportunity for the LED Flood light 10W to enter the field of interior lighting.

Less concern, however, that the amount of radiation generated by the LED of each light point is not large, is far less than the HID (high intensity discharge) light source, but it can be a very small energy concentrated in a certain direction. This also means that, although the LED unlike the laser is not as strong, but the local light intensity hazard should also be given special attention.

Insiders pointed out that the LED are mostly still in the sample stage, mainstream or traditional lighting products in the market, but the LED stage of the product will soon be full arrival. Once the LED into the product stage, IEC / EN 62471 must be mandatory to execution, related testing laboratories should have the ability to match or photobiological safety hazards may occur.

Comment:

Indeed, the led driver 120w    into the interior lighting, security issues will become more prominent, if made of spotlights, table lamps, flashlights, laser lecture pen, will cause the interest of the child, its security has become more important . For example, a small laser lecture pen if exposed directly to the child's eyes, it will damage the retina of the eye of the child. LED illumination radiation intensity of the harm is an objective reality, is the most protective part.

Of course, the correct detection LED lighting evaluation of the radiation intensity is very important, very difficult. Even if the LED Floodlight 80W   module to achieve the requirements of the lighting does not necessarily meet the requirements; lighting should also consider the light distribution, maximum intensity direction than the human eye is very easy to identify, we must seriously look for. These are not just domestic issues, but also the international detection in the field bottleneck.

LED Spotlight 30W   is about to enter the home lighting on the occasion, I hope the entire industry can be developed as soon as the correct means of detection, and specify a qualified laboratory testing, so in order to minimize the harm from the potential to radically.

When I ran out of time to solder together my 7-segment name badge, I decided to just pack the hrmshield for Maker Faire Bay Area as I planned to go to Jeri Ellsworth's Bring-A-Hack dinner.  I was hesitant to do so as I still need to make a case for it, but it all worked out very well.  I was fortunate to meet Ian and Skyler from Dangerous Prototypes who were a blast to hang out with.  They were making a video of projects at Maker Faire and I ended up being in it, at around 2 minute mark:

I'd like to thank Eric Boyd for the HeartSpark, Jimmie Rodgers for the OpenHeart and Adafruit for the logger shield.  I wouldn't have even attempted this project if I didn't have their existing projects to leverage.

Cheers,

Drew

Chip-making giant ARM has claimed that despite stiff competition from Intel, it expects to establish a significant footing in the lucrative PC and server markets. Intel, of course, has a strong hold on the smartphone market and has significant financial muscle to call on.

However, Warren East, the Chief Executive Officer of ARM Holdings, explained that the firm has good reason to feel optimistic about its medium to long-term outlook. "Companies making processors based on ARM cores will take between ten to 20 per cent of the notebook PC market in 2014 or 2015," he commented. "That would be much higher penetration than Intel would make into the smartphone market."

ARM and Intel have been the most prominent forces in the mobile phone and PC markets for a number of years now. However, they both intend to broaden their horizons and move in on the turf of rival firms. They are not in direct competition with each other, though, as Intel supplies chips while ARM licences the processor core to chip-making partners.

Mr East speculated that Intel will enjoy a reasonable level of success in the smartphone market, but argued that its penetration rate will peak at around ten per cent. "It's going to be quite hard for Intel to be much more than just one of several players. But they'll be a perfectly credible player," Mr East remarked.

He observed that ARM has a distinct advantage in that its processors will be lower in cost than those from Intel. Consequently, Mr East added, ARM can rightly expect to see its market share steadily increase over the coming years.

   LED electroluminescence principle of solid semiconductor light source, with rich colors, compact, high brightness, long life, low operating voltage, safe to use, fast response, 0 to 100% adjustable light of LED 10w  output, impact resistance and anti-vibration many advantages, including ultraviolet and infrared radiation. The application range is gradually expanding, with a good prospect. The high cost of a single package of high-power high-brightness LED and a point source, therefore from a wide range of practical and still have time. Into the practical power of the single high-brightness  is very small in most of the actual use of the occasion need light-emitting plane, must be arranged in accordance with the requirements of multiple LED 120w  combination, on the one hand to meet a wider range than the high brightness, dynamic display, the color changes and other application requirements, matched with the LED drive drive the other hand, to meet the matching requirements. Common form of connection Applications by a number of LEDs arranged in accordance with certain laws and the combination of a common form of connection, there are four main, respectively, are described below. 1, a whole series of Generally simple series connection method LED1-n-connected end to end, the current flowing through the LED work equal. For the same specifications and batch  , the voltage on the single LED  3w may have slight differences, but the LED is a current device, thus ensuring their luminous intensity is consistent. Therefore, the simple form of LED series circuit is simple, and convenient links. However, due to the LED1-n-two of the series form, when one   open-circuit fault occurs, will cause the  high power LED light string off, affecting the use of reliability. Series with bypass links as the 1.1 improvements. Each LED in parallel in this way the breakdown voltage slightly higher than the LED  operating voltage of Zener diode D1-n. LED work properly, due to the D1-n is not conducting, the current flowing through the LED1-n string, and equal, normal light LED1-n-string; when LED1-n-string in the damage caused by a light string is open, because D1 The turn-of-n to ensure that the current flows through the LED string, so only the failure of the high power  LED 1w fails, the entire light string is not extinguished. Relative to a connection, greatly increased the use of reliability.

Samsung graphene "miracle material" (via Samsung)

Graphene is back on the scene again, and this time it was sighted in the R&D labs at the Samsung Institute of Technology. SAIT recently announced that they have developed a new transistor architecture using the ‘miracle material.' Conventional silicon transistors have just about reached their speed limit even with a size reduction or shortening the connections the electrons have to travel, so in order to increase the electrons speed a new semiconductor material is needed.

Graphene (or even better; silicene) is thought to be the obvious solution since it has a high electron mobility capability 200 times that of silicon, but it does present one problem in that current can’t be switched off (typical gate of 1’s and 0’s except without the 0’s). Scientists have accomplished turning graphene into a zero-gap semiconductor to overcome this problem. However that comes with a price: speed reduction.

The engineers at the SAIT R&D labs have succeeded in creating a device, called ‘Barristor’ (graphene-silicon Schottky barrier), which can switch off the current with no speed reduction in electron flow. The device can turn electrical current on or off based on raising the height of the barrier (hence the name) by using a metallic semiconductor interface which prevents the current from flowing to the silicon. These barriers are normally used in diodes but have now been adapted by SAIT (9 patents alone for the Graphene Barristor) to develop graphene transistors.

This means that future electronics such as CPU’s will become infinitely faster (think 10-20GHz) over current processors with an overall reduction in size. If Samsung is successful in bringing the new transistors to the consumer market, it would be feasible to have an ultra-fast desktop computer the size of a smartphone in your pocket!

Cabe

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