Computed·Blg

Via SlashGear

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Researchers with the NASA Jet Propulsion Laboratory have undertaken a large project that will allow them to measure the carbon footprint of megacities – those with millions of residents, such as Los Angeles and Paris. Such an endevour is achieved using sensors mounted in high locations above the cities, such as a peak in the San Gabriel Mountains and a high-up level on the Eiffel Tower that is closed to tourist traffic.

The sensors are designed to detect a variety of greenhouse gases, including methane and carbon dioxide, augmenting other stations that are already located in various places globally that measure greenhouse gases. These particular sensors are designed to achieve two purposes: monitor the specific carbon footprint effects of large cities, and as a by-product of that information to show whether such large cities are meeting – or are even capable of meeting – their green initiative goals.

Such measuring efforts will be intensified this year. In Los Angeles, for example, scientists working on the project will add a dozen gas analyzers to various rooftop locations throughout the city, as well as to a Prius, which will be driven throughout the city and a research aircraft to be navigated to “methane hotspots.” The data gathered from all these sensors, both present and slated for installation, is then analyzed using software that looks at whether levels have increased, decreased, or are stable, as well as determining where the gases originated from.

One of the examples given is vehicle emissions, with scientists being able to determine (using this data) the effects of switching to green vehicles over more traditional ones and whether its results indicate that it is something worth pursuing or whether it needs to be further analyzed for potential effectiveness. Reported the Associated Press, three years ago California saw 58-percent of its carbon dioxide come from gasoline-powered cars.

California is looking to reducing its emissions levels to a sub-35-percent level over 1990 by the year 2030, a rather ambitious goal. In 2010, it was responsible for producing 408 million tons of carbon dioxide, which outranks just about every country on the planet, putting it about on par with all of Spain. Thus far into the project, both the United States and France have individually spent approximately $3 million the project.

Via FUTURITY

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A medical sensor that attaches to the skin like a temporary tattoo could make it easier for doctors to detect metabolic problems in patients and for coaches to fine-tune athletes’ training routines. And the entire sensor comes in a thin, flexible package shaped like a smiley face. (Credit: University of Toronto)

It looks like a smiley face tattoo, but a new easy-to-apply sensor can detect medical problems and help athletes fine-tune training routines.

“We wanted a design that could conceal the electrodes,” says Vinci Hung, a PhD candidate in physical and environmental sciences at the University of Toronto, who helped create the new sensor. “We also wanted to showcase the variety of designs that can be accomplished with this fabrication technique.”

The tattoo, which is an ion-selective electrode (ISE), is made using standard screen printing technique and commercially available transfer tattoo paper—the same kind of paper that usually carries tattoos of Spiderman or Disney princesses.

In the case of the sensor, the “eyes” function as the working and reference electrodes, and the “ears” are contacts for a measurement device to connect to.

Hung contributed to the work while in the lab of Joseph Wang, a professor at the University of California, San Diego. The sensor she helped make can detect changes in the skin’s pH levels in response to metabolic stress from exertion.

Similar devices are already used by medical researchers and athletic trainers. They can give clues to underlying metabolic diseases such as Addison’s disease, or simply signal whether an athlete is fatigued or dehydrated during training. The devices are also useful in the cosmetics industry for monitoring skin secretions.

But existing devices can be bulky or hard to keep adhered to sweating skin. The new tattoo-based sensor stayed in place during tests, and continued to work even when the people wearing them were exercising and sweating extensively.

The tattoos were applied in a similar way to regular transfer tattoos, right down to using a paper towel soaked in warm water to remove the base paper.

To make the sensors, Hung and colleagues used a standard screen printer to lay down consecutive layers of silver, carbon fiber-modified carbon and insulator inks, followed by electropolymerization of aniline to complete the sensing surface.

By using different sensing materials, the tattoos can also be modified to detect other components of sweat, such as sodium, potassium, or magnesium, all of which are of potential interest to researchers in medicine and cosmetology.

An article describing the work has been accepted for publication in the journal Analyst.

Via dvice

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Well, this is a little unsettling: it turns out that Wi-Fi signals are slightly affected by people breathing, and with the right tech someone could pinpoint where you are in a room from afar using just Wi-Fi.

This was discovered when University of Utah researcher Neal Patwari was looking for a way to monitor breathing without using uncomfortable equipment. If you can track breathing using just a Wi-Fi signal, it'll make sleep studies easier for both researchers and subjects. And it worked! By laying in a hospital bed surrounded by a bunch of wireless routers, they were able to accurately estimate his breathing rate within 0.4 breaths per minute.

Now that this is known, it's only a matter of time until there's a way to detect people in rooms using Wi-Fi signals. But don't worry! If you're nervous, there's a simple solution: stop breathing.

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Article at the New Scientist

Via Daily Tech

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MicroGen Systems says its chips differ from other vibrational energy-harvesting devices because they have low manufacturing costs and use nontoxic material instead of PZT, which contains lead.

MicroGen Systems is in the midst of creating energy-scavenging chips that will convert environmental vibrations into electricity to power wireless sensors. 

The chip's core consists of an array of small silicon cantilevers that measure one centimeter squared and are located on a "postage-stamp-sized" thin film battery. These cantilevers oscillate when the chip is shook, and at their base is piezoelectric material that produces electrical potential when strained by vibrations. 

The current travels from the piezoelectric array through an electrical device that converts it to a compatible form for the battery. When jostling the chip by vibrations of a rotating tire, for example, it can generate 200 microwatts of power. 

Critics such as David Culler, chair of computer science at the University of California, have said that 200 microwatts may be useful at a small size, but other harvesting techniques through solar, light, heat, etc. are more competitive technologies since they can either store the electrical energy on a battery or use it right away. 

But according to Robert Andosca, founder and president of Ithaca, New York-based MicroGen Systems, his chips differ from other vibrational energy-harvesting devices because they have low manufacturing costs and use nontoxic material instead of PZT, which contains lead. 

Most piezoelectric materials must be assembled by hand and can be quite large. But MicroGen's chips can be made inexpensively and small because they are based on silicon microelectrical mechanical systems. The chips can be made on the same machines used to make computer chips. 

MicroGen Systems hopes to use these energy-harvesting chips to power wireless sensors like those that monitor tire pressure. The chips could eliminate the need to replace these batteries.

"It's a pain in the neck to replace those batteries," said Andosca. 

MicroGen Systems plans to sell these chips at $1 a piece, depending on the volume, and hopes to begin selling them in about a year.