From Charles Darwin on, evolutionary biologists have struggled to explain self-sacrificing behavior. If evolution is all about the survival of the fittest, then why do animals from bees to people help others when it can hurt them or their chances to reproduce? Simulations of miniature robots that "evolve" helping behaviors have now provided a possible answer, confirming a 47-year-old theory that recently has come under attack: We help those who are most related to us because they are able to pass some of our genes to the next generation.
For all organisms, the ultimate goal is to pass on one's genes. The problem with altruism is that sacrificing individual gains for the greater good can compromise that goal. In the 1960s, biologist W. D. Hamilton pointed out that, actually, one could still pass on one's genes, or at least some of them, by helping a relative. According to his kin selection theory, the closer the relative, the greater this indirect benefit and, therefore, the more the helper should be willing to sacrifice in assisting that relative.
Studies of ants, wasps, bees, and termites, among others, have borne out this idea. But researchers could never quite verify the theory because they couldn't pin down exactly what the cost and benefits were or study them over the many generations needed to see evolution in action. And recently a few researchers have challenged the idea that relatedness is necessary for altruism's evolution, though they have their own critics.
Laurent Keller of the University of Lausanne in Switzerland wondered if he could resolve the debate using a computer simulation. He and roboticists Markus Waibel and Dario Floreano, both from the Ecole Polytechnique Fédérale of Lausanne, started with real-life robots that are just a couple of centimeters high. The robots have two independently operating wheels and a "nervous system" composed of sensors and a camera, which allow them to detect small discs—a stand in for food.
Robots learning to share. Dario Floreano explains how the evolving robots work.
Credit: EPFL News
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The researchers then created virtual representations of these robots on a computer so that they could observe the robots' evolution over time. In real life, random mutations build up over many generations, leading to adaptations that help organisms better survive in their environment. In the simulation, the researchers replicated this process by randomly varying the strengths of the various connections that made up the robots' nervous systems. Some of these "mutations" helped the robots better gather the food disks, while some made the robots less efficient at the task.
The simulations ran for hundreds of rounds, each time selecting the best food gatherers and culling the others. The process mimics natural selection, as only the most "fit" robots multiply (in clone form) in subsequent rounds. Every so often, the researchers checked their simulation results by programming a real robot with the same set of mutations. The virtual and real robots behaved similarly, says Floreano.
Once the team was comfortable with the virtual evolution environment it had set up, it added a new twist: It allowed the robots to share food disks with each other. If Hamilton's hypothesis was correct, "successful" virtual robots were likely to be those that were closely related and shared food with each other; that would help to ensure that at least one of them -- and some of the genes of both—would make it to the next round. (Two robots with a modest amount of food disks would both be more likely to be cut from the simulation, but if one robot gave all of its food to a second robot, that second robot would likely make the next round.) And indeed, altruism quickly evolved in the simulation, with greater food-sharing in groups where robots were more related, the researchers report online today in PLoS Biology. The more closely related the robots, the quicker they cooperated. "It shows how general the [theory] is, whether you are an insect, a human or a robot," says Floreano.
"This is a very original approach," says evolutionary biologist Jacobus Boomsma of the University of Copenhagen in Denmark. "The results are remarkably clear cut, given all the messy dynamics that might have appeared ... and show convincingly how tremendously robust Hamilton's rule is."
But Harvard University theortician Martin Nowak is more cautious about drawing conclusions based on computer simulations. Virtual robots are not a stand in for real life, he says. "[The work] tells us nothing about whether Hamilton's rule makes a correct prediction for actual biological systems," he says.
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Even Robots Can Be Heroes
Sunday, May 29, 2011
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How to reset printer
Saturday, May 28, 2011
Resetting an HP laser printer
There is a technique known as cold resetting. It basically will set all your HP printer settings to the factory default levels. It is important to note that any settings made at the control panel of your printer are going to be reset. Hence, in case you happen to have a JetDirect card then even the IP address will be reset to the factory defaults. You can try to reset NVRAM. To do this, switch off your HP printer and then hold down the ‘Go’ key for around 20 seconds while switching the printer back on again.
- HP 1200 and 1100 models resetting: To do this, simply change the data by going into the service mode. This is applicable if your HP printer has a display panel. Otherwise you need to hold down the ‘Go’ button for around 5 seconds while the printer is switched on.
- HP 2100 printer resetting: You need to press the ‘job cancel’ key after switching off the printer. Then switch the printer on and only then release the key called ‘job cancel.’
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The Positive Side of Remanufactured Printer Toner Cartridges and Printer Cartridges
Online Tech Support for Printers – An Overview
Overview of Printers – Solving Dell Printer Repair Issues and Others
- HP 2200 printer resetting: Switch off your printer and then hold down the ‘Go’ key. Switch back the printer on while holding the ‘Go’ button till the light comes on. Then release the button.
- HP 6P and 5P models resetting: Switch off your printer and then press the ‘reset’ button and within 20 seconds switch on the printer back again.
Resetting a Dell printer
You can reset your Dell printer fairly easily by simply double-clicking on the ‘Reset Dell Printer’ icon. You can reach this icon by clicking on the folder ‘UAN’, then clicking on ‘System Utilities’ and you should find the icon. However, one word of caution – this method will function only if the USB cable has been directly connected from the PC to the printer.
Resetting a Lexmark printer
You will firstly need to switch off your printer. Then simultaneously press the RETURN and READY keys while switching the printer on. This will take you to the Diagnostics Mode. The display unit will show the message ‘Performing self test’. Choose ‘Maintenance count’. Reset the count to make it zero. Then select the RETURN key and go back Diagnostics Mode. Then you can reset the printer to go back to the normal mode.
Resetting Brother Printer
You need to keep pressing the DOWN or UP keys a couple of times till you see ‘Maintenance 99’ displayed on the display. Then hold down the ‘Set’ button to go to standby mode. Please note that if you press the exit key only after typing in a single digit then the machine goes to maintenance mode in initial stages.
Resetting Samsung printer
You need to press the following keys in quick succession – MENU # 1 9 3 4. Then you should see a message on your display saying ‘TECH.’ Then again select the MENU key followed by ENTER. The display will now show ‘TECH MODE.’ Then select the ‘<’ key two times. Your operator panel should show ‘NEW CARTRIDGE’. Then select ENTER. Now the panel will show [YES]. Select ENTER key again. You can exit from this mode by pressing MENU # 1 9 3 4 again one after another.
Read more: http://www.articlesbase.com/hardware-articles/how-to-reset-your-printer-troubleshooting-for-resetting-your-hp-dell-lexmark-brother-or-samsung-printers-362933.html#ixzz1NRMfwAsi
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Ipod nano
Thursday, May 26, 2011
In this age in time, numerous men and women have been provided prompt entry to new music through the creation of mp3s and mp4s exclusively the iPod Nano. This digital media player was formally designed and copyrighted by the organization Apple. This iPod design was the successor of the iPod Mini which was between the incredibly first batch of mp3s released by its manufacturing provider. Previously considering that the Nano's introduction to the earth market, the consumers' specification requirements changed and advanced into far more difficult concepts, which is why this distinct design like several other iPods underwent cosmetic, application, and hardware improvements above the a long time and at this time, Apple is now serving the sixth era iPod Nano.
Water for Elephants
Ahead of the iPod Nano's up to date and present-day capabilities which are now what people are raving for, its noticeable attribute was its entire body dimensions. This songs gadget was incredibly thin and compact that you can have it with you wherever you go devoid of obtaining to be troubled about carrying an added load. Also, this product was also a hit to fitness lovers for the reason that they were presently in a position to jog and do aerobic exercising when listening to their favourite songs, all they necessary to purchases was an excess accessory which is an armband which homes the iPod securely and they're all set to go.
As stated earlier, the iPod Nano underwent particular changes in each era that went by. When the 2nd generation was released, customer demands enhanced by a outstanding proportion simply because this product was again lighter in bodyweight than the previous design in addition, other specs ended up enhanced like the human body substance, the exhibit settings, the battery daily life, and the storage measurements, and there were also extra capabilities like uncomplicated lookup solutions. Immediately after a couple of months, the 3rd generation Nano was released. This model was scaled-down in body dimensions but had a even larger display that all the prior versions. In this era, end users had been definitely in a position to check out total duration videos, and cover movement exhibit for each and every song or album was definitely attainable. Mainly because of this added feature, the battery daily life was all over again remodeled creating it previous for a lot more than 24 hrs of steady use. After one particular yr, Apple went back again to the previous iPod Nano form which was rectangular. This new generation iPod was provided two thumbs-up by critics for the reason that of its one particular of a variety characteristics which integrated the accelerometer that allowed music lovers to alter the music and the album cover by just shaking the gadget. The fifth generation Nano was aesthetically the exact as the former product but the most impressive attribute that it has which also surpassed even the other iPod models was it video taking capability. It was the initial iPod design with a developed-in digital camera.
The most up-to-date design which is the iPod Nano sixth generation became a great deal smaller than all the previous designs, but it now has the touchscreen ability for the reason that the full gadget is a screen. In conjunction with this, the extra functions in the other types like video clip taking capabilities, and voice recording talents were not introduced through to this newest Nano model.
Harry Potter and the Deathly Hallows, Part 1
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file Recovery 101
Wednesday, May 25, 2011
Digital storage device is a broad term for any type of electronic device that can have data saved onto it for later use. Common devices falling under this category are: USB flash drives, SD cards, XD cards, SSD drives, and hard drives. Chances are, if you own a computer, you own at least one of these devices. While we all would like to believe that these devices are 100% reliable, this is most certianly not the case. Unfortunately, when these devices break or fail, immediate panic ensues; this is largely due to the fact that most people have no idea what to do. Whether you ran over your flash drive, dropped your camera in the toilet, or you recieved one of the many terrifying error messages, stop hyperventalating and keep reading.
Step 1 - Is it Really Broken?
Physical damage and internal corruption of a device can happen in an endless number of ways, but understanding the potential problem can save you time and money. For a device that has been physically damaged or subjected to water, a simple analysis of the internal components can help determine the next step. If the outer casing is still intact, take a screwdriver or a razor and carefully remove it. Set the casing aside and inspect the now naked device for any signs of cracks, burns, or missing parts. If the device is a flash drive, there are 4 main components to look at in particular, the silver usb adapter that plugs into the computer, a green circuit board, a large black chip, and a smaller black chip. The large black chip is called the NAND chip, and this is the memory unit holding all of the data stored on the device. The smaller black chip is called the controller, and it works directly with the NAND chip in order to interpret the data stored on it. If there is any damage to these components, the help of a professional data recovery company is required; if the NAND chip is cracked or broken, say a little prayer for your drive and bury it in the backyard. If a device has been subjected to water, let it dry completely before attempting to plug it into a computer.
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Restore Memory Card Pictures
How to get back deleted data from different storages media devices
Recover Deleted Digital Photos
File Recovery Questions & Answers
Internal corruption often appears in the form of error messages. The 2 most common messages include: "this device is not recognized," and "this device needs to be formatted." In the case of the latter message, NEVER reformat your device if it has important data on it; this will make the files impossible to recover.
Step 2 - Finding the Right Data Recovery Company:
The best place to go for data recovery service is the place with the most experience. Thankfully the internet allows us to see details about a particular website and/or company, making it easier to sort out the newbies from the veterans. It's generally safe to say a company that has been in business for over 5 years has a good understanding of their industry. Data recovery companies are like a fine wine, they only get better with age; they refine new techniques and acquire the latest technologies while the newer companies are left learning the ropes through trial and error.
While the age of a company in this industry is an important variable, doing a little research can also determine the quality and reputation of their services. Press articles and consumer testimonials can be deciding factors in choosing the right one. Referrals or commendations from federal agencies and huge corporations are good things to look for. If an organization like NASA trusts their stuff with a company, chances are it's a safe bet. A good example of this is the commendation given to the company eProvided Data Recovery for their support in recovering the mission data from the prototype Helios aircraft after it crash landed into the Pacific Ocean.
Pricing is, and forever will be, a factor in any kind of service. There are masses of data recovery companies out there that will try and lure you in with flat rate pricing. While this may seem attractive, you'll either be overpaying for a simple recovery that requires little work, or they wont recover your data if it takes too many hours of work. Data recovery works best with variable pricing; simple recoveries from a company like eProvided cost as little as $20, and they offer pricing options to fit any budget if the device requires more advanced methods of recovery.
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