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Sunday, 22 July 2012

LEDs: Its Begining Of End For The Traditional Light Bulbs



Incandescent light bulb

In the beginning, there was darkness.
Then came fire.
It wasn’t until the 19th century that artificial light was first generated. The big leap came in the 1880s, when Thomas Edison lit homes with the incandescent bulb. Since then, for the next 130 years, incandescents ruled the nights, the roads, and especially the Christmas tree.
But now, the incandescent light bulb, one of the most venerable inventions of its era but deemed too inefficient for our own, will be phased off the U.S. market beginning in 2012 under the new energy law just approved by Congress.  In Europe alsom the stage has been set for the imminent death of the incandescent light bulb. And the rest of the World is also following the same. Already many stores across the world stopped stocking the good old bulbs already.
The days of the traditional incandescent bulb look numbered because these electricity-sapping glass orbs have fallen out of favour with environmentally-conscious governments and consumers.
Moving to more efficient lighting is one of the lowest-cost ways to reduce electricity use and greenhouse gases. In fact, it actually will save households money because of lower utility bills. Ninety percent of the energy that an incandescent light bulb burns is wasted as heat.

LED and it parts
And waiting in the wings is a new breed of hi-tech light based on the humble LED (light-emitting diode), the small lights found in everything from TV remote controls to bike lights. Not only do they promise to solve the bulb’s environmental woes, their backers say they will also respond intelligently to your surroundings and even influence the way we behave.
Efficient LED technology looks set to flick the switch on traditional incandescent lightbulbs forever, say researchers.
Already, the efficiency and long life of LEDs is making them a popular – if costly – option in places where changing bulbs is inconvenient or expensive, such as in motorway lights, traffic signals, airport runways or on large buildings and bridges. For example, the Louvre museum in Paris is currently replacing 4,500 bulbs with LED equivalents, a change that is expected to result in a 73% reduction in energy consumption. Plans are also in place to replace the 25-year-old lighting system that illuminates Tower Bridge in London with LED lighting in time for the 2012 Olympic Games.

An assortment of LED lightbulbs that are commercially available as of 2010 as replacements for screw-in bulbs
Of course, the death warrant for the incandescent bulb has been signed before. Compact fluorescent lamps (CFLs) – or energy efficient bulbs, as they are more commonly known – were supposed to spell the end of the light bulb in the 1970s. But despite rising to prominence in the 90s and constantly improving, they have failed to deliver on their promise. In part this is down to them costing more than regular bulbs, taking an age to warm up and often producing low quality light. And that is without even mentioning the environmental concerns over bulbs that contain mercury.
LEDs, it is claimed, will help overcome these problems. These tiny lights were invented by GE in the early 1960s and were initially only available in red, a property that defined the look of early pocket calculators and digital watches. Over the years, however, more colours have appeared.
People still use vacuum tubes for some applications, and similarly incandescent bulbs may never go away completely. But it is not a question of if, but of when LED lighting will be the norm throughout the world.
We are only just at the start of the LED lighting revolution, and you may never look up at the ceiling in the same way again.

Friday, 6 July 2012

Apple's Jobs tapped France 3615 for pre-internet ideas


Apple's Jobs tapped France 3615 for pre-internet ideas


The man who turned Apple into a web-connected empire of consumer gadgets drew some of his inspiration from a table-top box that wired French households to networked information way before the arrival of mass Internet, a French telecoms engineer says.
Long before hundreds of millions of homes worldwide began connecting to the Internet in the 1990s, France's Minitel box, the steam train of the online world, attracted the attention of Apple Inc's now deceased founder, Steve Jobs.
The clunky Minitel, pulled out of service at the end of June, was used by some 25 million people in France at the time for services ranging from checking the weather to making travel reservations and posting small ads.
"He bought one and took it to bits to see how it worked," Gerard Thery, one of the Frenchmen behind the 1982 launch of the Minitel system, told business newspaper Economie Matin.
Two decades of Internet sealed the fate of what once looked like a technological wonder that might conquer the world with a then wide range of shopping and travel booking services, accessible via the dial-up code 3615.
Its famous "Minitel Rose" sex chat lines were blamed for the astronomical phone bills of many unwitting customers.
Originally designed by France Telecom as an online directory to save paper, the Minitel never caught on abroad and was used by fewer and fewer French in recent years as the Internet, and the flashy gadgets made by companies like Apple, rendered it obsolete.

Gap between Mac and PC sales the smallest in 15 years


Gap between Mac and PC sales the smallest in 15 years


Apple has been on one hell of a tear lately. The company's signature iPhone dominates the smartphone market. Apple's new iPad is, by far, the best selling tablet being sold today. There's only one market where Apple is still playing catch up: Computer sales, an arena where PCs still dominate. But even there, Apple can find a silver lining: CNN is reporting that the gap between Mac sales and PC sales is the smallest its been since the 1990s.
Currently, PCs are outselling Macs by a ratio of about 20 to 1. That's a huge lead, but Apple has been steadily closed the gap over the last decade from its 2004 low of 55 to 1. When you factor in mobile devices such as phones and tablet computers, the PC vs. Mac gap closes to a mere 2 to 1, with Apple likely to draw even within the next year or two.
According to tech analyst Horace Dediu of Asymco, the secret to Apple's recent success is the MacBook. "The MacBook became easily differentiable as a 'better' laptop. It was not faster, did not have more storage or any key metrics being used to sell PCs. It was just better as an integrated product." And given the splash that the new MacBook Pro with Retina display is making in tech circles, Apple may wind up seeing yet another strong boost in their market share.

Milky Way galaxy at its best in July night sky


Milky Way galaxy at its best in July night sky



It's possible that most people on Earth have never seen the Milky Way, the galaxy in which we live. The Milky Way used to be a part of every human's life experience, but now that the majority of mankind lives in cities, with their light pollution, the Milky Way is rarely seen.
Our Milky Way galaxy is at its best for the next couple of weeks, but most of you will need to make a special effort to see it. It will probably require a drive of an hour or more to reach a dark enough location, where the Milky Way will be visible. Then it will require another 20 minutes for your eyes to become adjusted to the dark.
What will you see? Not the brilliant array of stars you see in photographs made with long exposures. The real Milky Way looks like a faint band of moonlit cloud arcing across the sky. Your eyes cannot resolve it into individual stars. 
No one knew it was made up of stars until Galileo first turned his telescope on it in 1609; this was one of his major discoveries. It wasn't until a couple of centuries later that astronomers began to realize that this band of stars was in fact the local version of the "spiral nebulae" that astronomers were discovering all over the sky.
The final clue to the puzzle was the realization that stars were all grouped into huge islands called galaxies, each containing many billions of stars. The Milky Way is our local galaxy.
Even today, beginners in astronomy often get confused by the two meanings of "Milky Way." It can be used in its original sense to refer to the faint band of glow arching across the sky, or in its modern sense referring to the galaxy in which the sun resides.
Seeing the Milky Way
When amateur astronomers refer to the Milky Way, they usually refer to the faint band in the sky, although any time you look anywhere in the sky, all the stars you see are part of the Milky Way because we are in the Milky Way.
To see what the ancients called the Milky Way, you must first find a truly dark location. The maps on this web site show the areas in the world with the brightest and darkest sky. If like most people on Earth you live in a city, you can probably identify it as one of the white splotches. Use the maps to identify a green, blue, or black location near you; that’s where you must go if you want to find the Milky Way.
But wait! Don’t try to spot the Milky Way tonight, because there is still an almost full moon in the sky. Wait a few nights until the moon has moved on in its monthly trip around the Earth.
When you get to your dark night sky, you may still need to block any nearby lights from your view. Then you will need to wait about 20 minutes for your eyes to adapt to the dark. Then, look towards the south in the sky.
If you live in the Northern Hemisphere, the center of the Milky Way will be low in the southern sky, and the band of the Milky Way will sweep upwards in an arch across the eastern sky to the northern horizon. If you live in the Southern Hemisphere, the center of the Milky Way will be almost overhead, and the band will sweep from your sothwestern horizon to your northeastern horizon.
Look for a faint silvery or milky cloud. Some parts will be brighter than others, giving a faintly mottled effect. These are star clouds, concentrations of millions of stars too faint to see as individual stars. You may also see some “holes” in the Milky Way: clouds of interstellar dust blocking our view of the stars beyond.
If you have a small binocular with you, say a 7x50 or 10x50, you can recreate Galileo’s discovery that stars make up the “glow” of the Milky Way. Even that small amount of magnification will be enough to resolve the Milky Way into thousands of stars.
What to see in the Milky Way galaxy
Start your tour of the Milky Way by looking for the constellations Scorpius and Sagittarius. Unlike many constellations, these form clearly recognizable patterns.
Scorpius looks like the scorpion it’s named for, complete with long curving tail with stinger at the end. Its heart is marked by the red giant star Antares. Sagittarius looks nothing like a centaur archer, but rather like a prosaic teapot, complete with handle, spout, and lid. If you live in the north, you will find these low in the southern sky; if you live in the south, they will be almost overhead.
Because the center of the Milky Way is the richest part of the sky, it is crammed with nebulas and open star clusters. To give you some idea of this richness, the chart shows the names of some of these objects. The brightness of the name indicates the brightness of the nebula or cluster.
The brightest objects are gathered around the center of our galaxy, right on the border between Scorpius and Sagittarius, between the scorpion’s stinger and the teapot’s spout.
But for now, don’t worry about the names. Just take in the rich clouds of light as you sweep upward from Scorpius and Sagittatius (in the Northern Hemisphere) or either left or right from overhead (in the Southern Hemisphere). You don’t need to put a name to sheer beauty.

Active sunspot shoots off intense new solar flare


Active sunspot shoots off intense new solar flare


The Solar Dynamics Observatory (SDO) captured this image of the sun during an M6.1 flare that peaked at 7:44 AM EDT on July 5, 2012. The image is shown in the 304 Angstrom wavelength, which is typically colorized in red.

The sun fired off yet another intense solar flare today (July 5), the latest in a series of storms from a busy sunspot being closely watched by space telescopes and astronomers.
NASA's Solar Dynamics Observatory snapped a daunting new image of a strong M-class solar flare that peaked this morning at 7:44 a.m. EDT (1144 GMT). The M6.1 flare triggered a moderate radio blackout that has since subsided, according to officials at NASA and the National Oceanic and Atmospheric Administration (NOAA).
The eruption came from a sprawling sunspot, called Active Region 1515, which has been particularly dynamic this week. In fact, the sunspot region has now spewed 12 M-class solar flares since July 3, NASA officials said in a statement today. The sunspot region is huge, stretching more than 62,137 miles long (100,000 kilometers) in length, they added.
This sunspot region has also produced several coronal mass ejections (CMEs), which are clouds of plasma and charged particles that are hurled into space during solar storms. Powerful CMEs have the potential to disrupt satellites in their path and, when aimed directly at Earth, can wreak havoc on power grids and communications infrastructure.
The CMEs that were triggered by this week's solar flares, however, are thought to be moving relatively slowly, and will likely not hit Earth since the active region is located so far south on the face of the sun, NASA officials said.
But, the sunspot is slowly rotating toward Earth, and scientists are still monitoring its activity.
"Stay tuned for updates as Region 1515 continues its march across the solar disk," officials at the Space Weather Prediction Center, a joint service of NOAA and the National Weather Service, wrote in an update.
X-class solar flares are the strongest sun storms, with M-class flares considered medium-strength, and C-class the weakest. Today's M6.1 eruption is a little over half the size of the weakest X-class flare, NASA officials said.
Radio blackouts can occur when a layer of Earth's atmosphere, called the ionosphere, is bombarded with X-rays or extreme ultraviolet light from solar eruptions. Disturbances in the ionosphere can change the paths of high and low frequency radio waves, which can affect information carried along these channels.
Radio blackouts are categorized on a scale from R1 (minor) to R5 (extreme). An R2 radio blackout can result in limited degradation of both high- and low-frequency radio communication and GPS signals, NASA officials said.
The sun is currently in an active phase of its roughly 11-year solar weather cycle. The current cycle, known as Solar Cycle 24, is expected to peak in mid-2013.

Thursday, 14 June 2012

Climate balancing: sea-level rise vs. surface temperature change rates

Climate balancing: sea-level rise vs. surface temperature change rates



UNIVERSITY PARK, Pa. -- Engineering our way out of global climate warming may not be as easy as simply reducing the incoming solar energy, according to a team of University of Bristol and Penn State climate scientists. Designing the approach to control both sea level rise and rates of surface air temperature changes requires a balancing act to accommodate the diverging needs of different locations.
"Basic physics and past observations suggest that reducing the net influx of solar energy will cool the Earth," said Peter J. Irvine, graduate student, University of Bristol, UK, and participant in the Worldwide Universities Network Research Mobility Programme to Penn State. "However, surface air temperatures would respond much more quickly and sea levels will respond much more slowly."
Current solar radiation management approaches include satellites that block the sun, making the Earth's surface more reflective or mimicking the effects of volcanoes by placing aerosol particles in the upper atmosphere.
"These solar radiation management approaches could be cheaper than reducing carbon dioxide emissions," said Klaus Keller, associate professor of geosciences, Penn State. "But they are an imperfect substitute for reducing carbon dioxide emissions and carry considerable risks."
How well they work at reducing sea level rise or surface air temperatures depends on how they are implemented.
"Strategies designed to reverse sea-level rise differ from the strategies designed to limit the rate of temperature changes," said Ryan Sriver, research associate in geosciences, Penn State.
To stop or reverse sea-level rise, the incoming solar radiation would have to be decreased rapidly, but this approach would produce rapid cooling. Adopting a more gradual approach would reduce the risks due to rapid cooling, but would allow for considerable sea-level rise.
The researchers note that people living close to sea level are likely more concerned about sea-level rise than about the rates of surface temperature changes. In contrast, those living far from the oceans, are likely more concerned about rates of surface temperature changes that can influence agricultural or energy usage.
The researchers used a model to analyze the tension between controlling sea level rise and rates of surface temperature changes. They ran 120 scenarios with differing combinations of solar radiation management (SRM) including one called "business as usual," which has no SRM.
They note that their model includes many approximations. For example, it does not include a mechanistic representation of ice sheets. They also did not consider scenarios that combine solar radiation management and reducing carbon dioxide emissions.
They report in the current issue of Nature Climate Change that the forcing required to stop sea-level rise could cause a rapid cooling with a rate similar to the peak business-as-usual warming rate.
"While abrupt cooling may sound like a good idea, it could be more damaging than the increasing temperatures caused by increasing carbon dioxide," said Keller.
"The rate of cooling can be a problem if it exceeds the capacity of the plants and animals to adapt," said Sriver.
Another consideration when implementing solar radiation management approaches is that these approaches can require a long-term commitment. The researchers showed that "termination of solar radiation management was found to produce warming rates up to five times greater than the maximum rates under the business-as-usual scenario, whereas sea-level rise rates were only 30 percent higher."
To avoid such harsh changes, should SRM be discontinued, requires a slow phase out over many decades. This places a commitment on future generations.
The National Science Foundation, Penn State Center for Climate Risk Management and the Worldwide Universities Network at the University of Bristol partially funded this work.

How will the Earth system change in the future?


How will the Earth system change in the future?

As the world consumes ever more fossil fuel energy, greenhouse gas concentrations will continue to rise and Earth's average temperature will rise with them. The Intergovernmental Panel on Climate Change (or IPCC) estimates that Earth's average surface temperature could rise between 2°C and 6°C by the end of the 21st century.

Earth


Earth is a complex, dynamic system we do not yet fully understand. The Earth system, like the human body, comprises diverse components that interact in complex ways. We need to understand the Earth's atmosphere, lithosphere, hydrosphere, cryosphere, and biosphere as a single connected system. Our planet is changing on all spatial and temporal scales. The purpose of NASA's Earth science program is to develop a scientific understanding of Earth's system and its response to natural or human-induced changes, and to improve prediction of climate, weather, and natural hazards.
MODIS Image
This is a composite image of the North African Continent. A dust storm can be seen blowing off the coast of Morocco in the northwest corner.
Image: MODIS band combination 1,4,3.
A major component of NASA’s Earth Science Division is a coordinated series of satellite and airborne missions for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans. This coordinated approach enables an improved understanding of the Earth as an integrated system. NASA is completing the development and launch of a set of Foundational missions, new Decadal Survey missions, and Climate Continuity missions.
The Foundational missions are those missions in development at the time the decadal survey was published and include Aquarius, NPOESS Preparatory Project (NPP),Landsat Data Continuity Mission (LDCM), and Global Precipitation Measurement (GPM). The Decadal Survey missions are those guided by the decadal survey produced by the National Research Council of the National Academy of Sciences and published in 2007. These missions include Soil Moisture Active-Passive (SMAP), Ice, Cloud and land Elevation Satellite (ICESat-II), Hyperspectral Infrared Imager (HyspIRI), Active Sensing of CO2 Emissions Over Nights, Days, and Seasons (ASCENDS), Surface Water and Topography (SWOT), Geostationary Coastal and Air Pollution Events (GEO-CAPE), and Aerosol-Clouds-Ecosystems (ACE). Earth Venture, also a recommendation of the decadal survey, consists of low cost, competed suborbital and orbital missions as well as instruments for Missions of Opportunity.The Climate Continuity missions include Orbiting Carbon Observatory-2 (OCO-2), Stratospheric Aerosol and Gas Experiment – III (SAGE III), Gravity Recovery and Climate Experiment Follow-on (GRACE-FO), and Pre-Aerosol, Clouds, and Ocean Ecosystem (PACE).
Over the coming decades, NASA and the Agency's research partners will continue to pioneer the use of both spaceborne and aircraft measurements to characterize, understand, and predict variability and trends in Earth's system for both research and applications. Earth is the only planet we know to be capable of sustaining life. It is our lifeboat in the vast expanse of space. Over the past 50 years, world population has doubled, grain yields have tripled and economic output has grown sevenfold. Earth science research can ascertain whether and how the Earth can sustain this growth in the future. Also, over a third of the US economy - $3 trillion annually - is influenced by climate, weather, and natural hazards, providing economic incentive to study the Earth.
NASA Earth System Science conducts and sponsors research, collects new observations, develops technologies and extends science and technology education to learners of all ages. We work closely with our global partners in government, industry, and the public to enhance economic security, and environmental stewardship, benefiting society in many tangible ways. We conduct and sponsor research to answer fundamental science questions about the changes we see in climate, weather, and natural hazards, and deliver sound science that helps decision-makers make informed decisions. We inspire the next generation of explorers by providing opportunities for learners of all ages to investigate the Earth system using unique NASA resources, and our Earth System research is strengthening science, technology, engineering and mathematics education nationwide.

Ecosystem Science


Ecosystem Science

The Ecosystem Science Group conducts fundamental research to develop an understanding of mechanisms of terrestrial response to environmental change at multiple scales for the projection of the fate and function of terrestrial biomes in the future.
The Ecosystem Science Group conducts research to understand and predict environmental change impacts on carbon, water and nutrient cycles of terrestrial ecosystems and their feedbacks to climate and how changes in ecosystem structure and land use alter those biogeochemical feedbacks. It designs, constructs and operates targeted, large-scale, field experiments to predict vulnerability of terrestrial ecological systems to projected changes in climate and atmospheric composition and how those responses might alter both the delivery of ecosystem goods anCumulative Effects of Decadal CO2 Enrichment on Forest Soil Microbial Processes and Communitiesd services and the feedbacks from ecosystems to the atmosphere and climate. It also establishes measurements and experiments to obtain the knowledge required to reduce or eliminate critical uncertainties, and to identify and fill gaps in the representation of fundamental processes within existing ecological model at multiple scales.
Ecosystem Simulation Science advanced by our group organizes and extrapolates process understanding of ecological mechanisms for regional analysis and prognostic calculation of global terrestrial  biome functions




The Environmental Sciences Division


The Environmental Sciences Division (ESD) is an interdisciplinary research and development organization with more than 60 years of achievement in local, national, and international environmental research. Our vision is to expand scientific knowledge and develop innovative strategies and technologies that will strengthen the nation's leadership in creating solutions to help sustain the Earth’s natural resources. Scientists in ESD conduct research, develop technology, and perform analyses to understand and assess responses of environmental systems at the environment-human interface and the consequences of alternative energy and environmental strategies. We seek to understand how natural and anthropogenic factors (e.g., global and regional change, environmental stress, and energy production and use) interact to influence environmental systems and society. Our methods integrate field and laboratory methods with new theory, modeling, data systems, policy analysis, and evaluation to create solutions to complex environmental challenges.
We have six core areas of research that frame our objectives in advancing environmental science, technology, and policy:

Earth and Aquatic Sciences

Create and apply new knowledge across multiple scales to aid decision-makers on the stewardship of air, water, and land resources
  • Atmospheric and Aerosol Sciences
  • Ecological Assessment
  • Environmental Chemistry & Technology
  • Field- Scale Research
  • Subsurface Science
  • Sustainability & Technology Deployment

Ecosystem Science

Understanding mechanisms of organism-to-community responses to environmental changes at multiple scales to project the fate and function of ecosystems
  • Ecosystem Simulation Science
  • Experimental Terrestrial Ecology
  • Nutrient Biogeochemistry
  • Terrestrial Water-Carbon Cycles

Environmental Data Science & Systems

Provide data management and analysis for large, integrated environmental databases to the nation’s research community and policymakers
  • Atmospheric Radiation Measurements (ARM) Archive
  • Carbon Dioxide Information Analysis Center
  • ORNL Distributed Active Archive Center for Biogeochemical Dynamics(ORNL DAAC)
  • USA National Phenology Network (USA-NPN)
  • National Biological Information Infrastructure (NBII) Metadata Clearinghouse

Renewable Energy Systems

Develop methods and models; conduct analyses; and produce tools that address key issues at the intersection of science, technology, society, and policy
  • BioEnergy Resource & Engineering Systems
  • Energy Analysis
  • Landscape Ecology & Regional Analysis
  • Multi-Scale Energy-Environmental Systems
  • Society-Technology Interactions

Human Health Risk & Environmental Analysis

Conduct analyses for decision-makers to assess (1) emerging technologies and products and (2) methods for identifying and managing the hazards of energy and national security projects, as well as the disposition of their related wastes
  • Environmental Analysis
  • Risk and Regulatory Analysis
  • Toxicology and Hazard Assessment

Energy-Water-Ecosystem Engineering

Sustainable energy production and water availability in healthy ecosystems through technology development, systems analysis, and decision support.
  • Application Areas
    – Hydropower Technology RD&D
    – Marine and Hydrokinetic Energy RD&D
    – Thermoelectric Cooling Water Availability
    – Water Supply and Competing Water Use Analysis
  • Science-to-Energy Challenges
    – Joint optimization of ecological health and water-dependent energy production
    – Organism, population, and commnunity response to energy infrastructure perturbations
    – Role of climate variability in robust energy-water infrastructure design
    – Use of hydrodynamic modeling, advanced materials and sensors for water power cost-of-energy improvements