Tech Buzz: Meet Ritot - the first projection watch

 

It's been a long time since mankind has stopped peering into the sky at the sun to calculate the time. Clocks were invented for this purpose. The first clock was created thousands of years ago. There were various types of clock, including sundial, clepsydra, hourglass and others. 
    Since then, the evolution of clock has continued and brought to us the first wristwatch. Every year there emerge dozens of new models of wirstwatch, but the operating principle has not changed.
    We live in a new progressive millennium; everything around us progresses and develops. In our opinion, clock design should be both technically innovative and fashionable. Watches demonstrating that humanity does not stand still. These are the watches we bring into life.

read more at https://www.indiegogo.com/projects/ritot-the-first-projection-watch

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Science and Tech : NASA's Spitzer telescope witnesses asteroid smashup -Crash, bang, wallop

Nasa's Spitzer Space Telescope has spotted a huge eruption of dust around a young star. They believe the dust cloud was the result of a smashup between large asteroids.
This type of collision can eventually lead to the formation of planets, researchers say.
Scientists had been regularly tracking the star, called NGC 2547-ID8, when it surged with a huge amount of fresh dust between August 2012 and January 2013. "We think two big asteroids crashed into each other, creating a huge cloud of grains the size of very fine sand, which are now smashing themselves into smithereens and slowly leaking away from the star," said lead author and graduate student Huan Meng of the University of Arizona, Tucson.

The aftermath of a large asteroid impact around NGC 2547-ID8, a 35-million-year-old sun-like star. Nasa's Spitzer Space Telescope witnessed a giant surge in dust around the star, the result of two asteroids colliding.

read more at http://phys.org/news/2014-08-spitzer-telescope-witnesses-asteroid-smashup.html

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Science and Tech: Picturing Schrodinger's cat- Quantum physics enables revolutionary imaging method

The cats represent the famous Schrödinger cat paradox, in which a quantum cat closed in a box can be dead and alive at the same time. The dark and light cat bodies are images of a cardboard cut-out. They arise due to destructive and constructive quantum interference, respectively. In this experiment the photons that interact with the cardboard cut-out are not detected, while the images are obtained by detecting only photons that never interact with the object. Credit: Gabriela Barreto Lemos

Researchers from the Institute for Quantum Optics and Quantum Information (IQOQI), the Vienna Center for Quantum Science and Technology (VCQ), and the University of Vienna have developed a fundamentally new quantum imaging technique with strikingly counterintuitive features. For the first time, an image has been obtained without ever detecting the light that was used to illuminate the imaged object, while the light revealing the image never touches the imaged object.

In general, to obtain an image of an object, one has to illuminate it with a light beam and use a camera to sense the light that is either scattered or transmitted through that object. The type of light used to shine onto the object depends on the properties that one would like to image. Unfortunately, in many practical situations, the ideal type of light for the illumination of the object is one for which cameras do not exist.

read more at http://phys.org/news/2014-08-picturing-schrodinger-cat-quantum-physics.html

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Science and Tech:Towards more efficient solar cells

Potential use of a layer of silicon nanocrystals (large balls) and erbium ions (small balls) as a 'spectral shaper' for photovoltaic applications. This layer converts high-energy UV photons into infrared photons. These lower-energy photons are absorbed by an underlying solar cell. Credit: Fundamental Research on Matter (FOM)

A layer of silicon nanocrystals and erbium ions may help solar cells to extract more energy from the ultraviolet (UV, high-energy) part of the solar spectrum. Experimental physicists from the FOM Foundation, the STW Technology Foundation and the University of Amsterdam published this news in Nature Communications on 13th August 2014. When conventional silicon-based solar cells absorb UV light, much of its energy is lost in the form of heat. The researchers showed that this excess energy can be used to excite multiple erbium ions. This causes the ions to emit light, which can then be converted into electricity.

Conventional solar cells can only convert a small part of the solar spectrum into electricity efficiently. Low-energy light particles (photons) are not absorbed, as they do not have enough energy to bridge the band gap of the material from which solar cells are made. By contrast, high-energy photons can be absorbed, but in just a few picoseconds (10^-12 seconds) much of their energy is transformed into heat. This limits maximum efficiency to just 30 percent.

Fast and efficient

Saba Saeed and her colleagues have now shown that the conversion efficiency can potentially be increased by making better use of the energy contained in these high-energy photons. This can be achieved with a layer consisting of silicon dioxide, silicon nanocrystals (particles with a size of a billionth of a meter) and erbium ions. The silicon nanocrystals transfer its excess energy to the erbium ions, before it is lost as heat. This leads to the emission of several low-energy infrared photons per absorbed photon, which can produce extra electricity. Compared to sunlight concentrators, which sometimes also make use of rare-earth metals such as erbium, this technique holds the prospect of a higher efficiency.

Spectral shaper

While the process has been demonstrated experimentally, it has not yet been used in a photovoltaic architecture (a solar cell). In the future, a layer of silicon nanocrystals and erbium ions could be placed on top of solar cells as a 'spectral shaper', to enhance their efficiency. The 'spectral shapers' would convert high-energy UV photons to several low-energy photons, which can then be used to generate electricity in a solar cell.

read more at
Explore further: http://phys.org/news/2014-08-efficient-solar-cells.html

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Tech Ubuntu 14.04 update : Install Java JDK in Ubuntu 14.04 : the manual way

 how Install Java JDK in Ubuntu 14.04 : the manual way

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There is a similar answer on how to install JRE 8. Install Java JDK The manual way Download the 32bit or 64bit Linux "compressed binary file" - it has a ".tar.gz" file extension. Uncompress it tar -xvf jdk-8-linux-i586.tar.gz (32bit) tar -xvf jdk-8-linux-x64.tar.gz (64bit) JDK 8 package is extracted into ./jdk1.8.0 directory. N.B. check carefully this folder name since Oracle seem to change this occasionally with each update. Now move the JDK 8 directory to /usr/lib sudo mkdir -p /usr/lib/jvm sudo mv ./jdk1.8.0 /usr/lib/jvm/ Now run sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jdk1.8.0/bin/java" 1 sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.8.0/bin/javac" 1 sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/lib/jvm/jdk1.8.0/bin/javaws" 1 This will assign Oracle JDK a priority of 1, which means that installing other JDKs will replace it as the default. Be sure to use a higher priority if you want Oracle JDK to remain the default. Correct the file ownership and the permissions of the executables: sudo chmod a+x /usr/bin/java sudo chmod a+x /usr/bin/javac sudo chmod a+x /usr/bin/javaws sudo chown -R root:root /usr/lib/jvm/jdk1.8.0 N.B. remember - Java JDK has many more executables that you can similarly install as above. java, javac, javaws are probably the most frequently required. This answer lists the other executables available. Run sudo update-alternatives --config java You will see output similar one below - choose the number of jdk1.8.0 - for example 3 in this list (unless you have have never installed Java installed in your computer in which case a sentence saying "There is nothing to configure" will appear): $ sudo update-alternatives --config java There are 3 choices for the alternative java (providing /usr/bin/java).

to enable Mozilla Firefox plugin:

32 bit:  ln -s /usr/lib/jvm/jdk1.8.0/jre/lib/i386/libnpjp2.so ~/.mozilla/plugins/    64 bit:  ln -s /usr/lib/jvm/jdk1.8.0/jre/lib/amd64/libnpjp2.so ~/.mozilla/plugins/

N.B. you can link the plugin (libnpjp2.so) to /usr/lib/firefox/plugins/ for a system wide installation, For Ubuntu 13.10 path to plugin directory is /usr/lib/firefox/browser/plugins/

Depending on your configuration, you might need to update the apparmor profile for firefox (or other browsers) in /etc/apparmor.d/abstractions/ubuntu-browsers.d/java

read more and completely at http://askubuntu.com/questions/56104/how-can-i-install-sun-oracles-proprietary-java-jdk-6-7-8-or-jre/55960#55960

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Science and Tech: Japanese universities develop new world's fastest camera

Schematic of STAMP. Credit: (c) Nature Photonics (2014) doi:10.1038/nphoton.2014.163

Researchers working at two universities in Japan have jointly developed what is being described as the world's fastest camera. A photo-device with a frame interval of 4.4 trillion frames per second. In their paper published in the journal Nature Photonics, the team describes how their camera works, its capabilities and the extensive work that went into its creation.

High speed cameras allow researchers and everyday people alike the ability to see things that they wouldn't be able to otherwise, from slowdown of sports play to mechanical processes. Prior to the announcement in Japan, the fastest cameras relied on what's known as a pump-probe process—where light is "pumped" at an object to be photographed, and then "probed" for absorption. The main drawback to such an approach is that it requires repetitive measurements to construct an image. The new camera is motion-based femtophotography, performing single-shot bursts for image acquisition, which means it has no need for repetitive measurements. It works via optical mapping of an object's spatial profile which varies over time. Its abilities make it 1000 times as fast as cameras it supersedes. In addition to the extremely high frame rate, the camera also has a high pixel resolution (450 × 450).

Developed by a joint team of researchers from Keio University and the University of Tokyo, the camera is set to capture images of things and events that until now have not been impossible. With technology the team has named Sequentially Timed All-optical Mapping Photography, or STAMP for short, the camera is poised to be used to capture chemical reactions, lattice vibrational waves, plasma dynamics, even heat conduction, which the researchers note occurs at approximately a sixth the speed that light travels.

read complete details at http://phys.org/news/2014-08-japanese-universities-world-fastest-camera.html

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VLSI UPDATE: Researchers build first 3D magnetic logic gate

Magnetic force microscope images of the 3D magnetic logic gates, each containing three input magnets and one output magnet. Numbers show the magnetization states of the output magnet for all input configurations. Credit: Eichwald, et al. ©2014 IOP

The integrated circuits in virtually every computer today are built exclusively from transistors. But as researchers are constantly trying to improve the density of circuits on a chip, they are looking at alternative ways to build circuits. One alternative method uses nano-sized magnets, in which the magnets possess two stable magnetic states that represent the logic states "0" and "1."

Until now, nanomagnetic logic (NML) has been implemented only in two dimensions. Now for the first time, a new study has demonstrated a 3D programmable magnetic logic gate, where the magnets are arranged in a 3D manner. In comparison to the 2D gate, the 3D arrangement of the magnets allows for an increase in the field interaction between neighboring magnets and offers higher integration densities.

The researchers, Irina Eichwald, et al., at the Technical University of Munich in Munich, Germany; and the University of Notre Dame in Notre Dame, Indiana, US, have published their paper on the 3D magnetic logic gate in a recent issue of Nanotechnology.

"We showed for the first time that magnetic field coupling can be exploited in all three dimensions in order to realize magnetic logic computing circuitry, and therefore paves the way for new technologies, where high integration densities combined with low power consumption can be achieved," Eichwald told Phys.org.

The 3D magnetic logic gate consists of three input magnets that influence the magnetic state of one output magnet. To prepare the output magnet, the researchers used a focused ion beam to irradiate a 40 x 40-nm area of the magnet to destroy its crystalline structure, creating a domain wall. When the magnetic fields from the three input magnets are placed within 100 nm of the irradiated spot, the domain wall's magnetic state can be controlled. As a result, the output magnet can be switched between the "0" and "1" states.

SEM image of the 3D magnetic logic gate. The input magnet I3 is located in a different layer than the rest of the magnets, making the gate three-dimensional. Credit: Eichwald, et al. ©2014 IOP

One important feature of the 3D magnetic logic gate is that one of the input magnets is arranged in an extra layer in comparison to 2D magnetic logic gates. Adding a third dimension enhances the amount of magnetic area surrounding the output magnet by 1/3, and also increases the influence of each input magnet by 1/6. These stronger magnetic effects reduce the error rate and improve the functionality of the gate. The input magnet in the third dimension also programs the gate to operate as either a NOR or NAND gate.

NML has several potential advantages compared to transistors. One is that there is no need for electrical wiring or interconnects because the computation is performed entirely by magnetic interactions between neighboring magnets. NML also operates with low power consumption, which in turn enables the combination of logic and memory functionality in a single device.

Read more at: http://phys.org/news/2014-08-3d-magnetic-logic-gate.html#jCp

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Tech Update: WIFI terms Understanding the Network Terms SSID, BSSID, and ESSID

Understanding the Network Terms SSID, BSSID, and ESSID

The terms BSSID, ESSID, and SSID are all used to describe sections of a wireless network (WLAN)—the three terms have slightly different meanings. As a wireless user you are concerned only with the broadcast SSIDs that let you connect to a wireless network. As an administrator, you also need to keep track of BSSIDs and, to a lesser degree, ESSIDs.

This topic describes:

An SSID is the Name of a Network

Because multiple WLANs can coexist in one airspace, each WLAN needs a unique name—this name is the service set ID (SSID) of the network. Your wireless device can see the SSIDs for all available networks—therefore, when you click a wireless icon, the SSIDs recognized by device are listed. For example, suppose your wireless list consists of three SSIDs named Student, Faculty, and Voice. This means that an administrator has created three WLAN Service profiles and, as part of each WLAN service profile, provided the SSID name Student, Faculty, or Voice. (For directions to create a WLAN Service profile, see Creating and Managing a WLAN Service Profile.)

Figure 1: Radios can have up to 32 SSIDs

As a WLAN user, you are concerned only with the SSIDs. You select one from the list on your laptop or other device, provide your username and a password, and use the SSID. You might not have access to all SSIDs—the authentication and access privileges are usually different for different WLANs and their associated SSIDs.

BSSIDs Identify Access Points and Their Clients

Packets bound for devices within the WLAN need to go to the correct destination. The SSID keeps the packets within the correct WLAN, even when overlapping WLANs are present. However, there are usually multiple access points within each WLAN, and there has to be a way to identify those access points and their associated clients. This identifier is called a basic service set identifier (BSSID) and is included in all wireless packets.

Figure 2: Each Access Point Has Its Own BSS

As a user, you are usually unaware of which basic service set (BSS) you currently belong to. When you physically move your laptop from one room to another, the BSS you use could change because you moved from the area covered by one access point to the area covered by another access point, but this does not affect the connectivity of your laptop.

As an administrator, you are interested in the activity within each BSS. This tells you what areas of the network might be overloaded, and it helps you locate a particular client. By convention, an access point’s MAC address is used as the ID of a BSS (BSSID). Therefore, if you know the MAC address, you know the BSSID—and, because all packets contain the originator’s BSSID, you can trace a packet. This works fine for an access point with one radio and one WLAN configured.

Most often, there are different BSSIDs on an access point for each WLAN configured on a radio. If you have an access point with 2 radios and 32 WLANs configured on each, you would have 64 BSSIDs plus the base access point BSSID. To accommodate the multiple BSSIDs, each access point is assigned a unique block of 64 MAC addresses. Each radio has 32 MAC addresses and supports up to 32 service set identifiers (SSIDs), with one MAC address assigned to each SSID as a basic service set identification (BSSID). All MAC addresses for an access point are assigned based on the base MAC address of the access point.

Note: The access point MAC address block is listed on a label on the back of the access point.

To view a list of SSIDs for a network, look at the list of WLAN Service Profiles in Network Director.

Ad-Hoc Networks Do Not Have a MAC Address

Every BSS needs a BSSID, and using the access point’s MAC address works fine most of the time. However, an ad-hoc network, a network that forwards traffic from node to node, has no access point. When a BSS does not have a physical access point, in an ad-hoc network for example, the network generates a 48-bit string of numbers that looks and functions just like a MAC address, and that BSSID goes in every packet.

An ESS Consists of BSSs

An extended basic service set (ESS) consists of all of the BSSs in the network. For all practical purposes, the ESSID identifies the same network as the SSID does. The term SSID is used most often.

read more http://www.juniper.net/techpubs/en_US/junos-space-apps12.3/network-director/topics/concept/wireless-ssid-bssid-essid.html

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