Artificial muscle computer performs as a universal Turing machine

ORIGINAL: Physorg

by Lisa Zyga

March 28, 2013 

An illustration of Wolfram’s “2, 3” Turing machine, the simplest known universal Turing machine that can solve any computable problem. A machine head reads the tape, decides what to do based on the data it sees plus its internal state (1 or 0), and then write the data and moves a step left or right. The researchers here realized this Turing machine using artificial muscles to help perform logic functions and memory functions. Credit: O’Brien and Anderson. ©2013 American Institute of Physics

(Phys.org) —In 1936, Alan Turing showed that all computers are simply manifestations of an underlying logical architecture, no matter what materials they're made of. Although most of the computer's we're familiar with are made of silicon semiconductors, other computers have been made of DNA, light, legos, paper, and many other unconventional materials. 

Now in a new study, scientists have built a computer made of artificial muscles that are themselves made of electroactive polymers. The artificial muscle computer is an example of the simplest known universal Turing machine, and as such it is capable of solving any computable problem given sufficient time and memory. By showing that artificial muscles can "think," the study paves the way for the development of smart, lifelike prostheses and soft robots that can conform to changing environments.

The authors, Benjamin Marc O'Brien and Iain Alexander Anderson at the University of Auckland in New Zealand, have published their study on the artificial muscle computer in a recent issue of Applied Physics Letters.

"To the best of our knowledge, this is the first time a computer has been built out of artificial muscles," O'Brien told Phys.org. "What makes it exciting is that the technology can be directly and intimately embedded into artificial muscle devices, giving them lifelike reflexes. Even though our computer has hard bits, the technology is fundamentally soft and stretchy, something that traditional methods of computation struggle with."

Video of the artificial muscle computer at work. Credit: O’Brien and Anderson. ©2013 American Institute of Physics

The artificial muscle computer is modeled on Stephen Wolfram's "2, 3" Turing machine architecture, which is the simplest known universal Turing machine. It consists of a machine head that reads symbols stored on a tape, and then based on the symbols and its own state (0 or 1), it follows a set of instructions that tells it what to write and store. The 2, 3 Turing machine is ideal to build with artificial muscles because of its simplicity. The researchers could theoretically solve any computational problem using just 13 muscles.

By expanding and contracting, the artificial muscles performed a variety of mechanisms involved in the computing process. For example, the muscles pushed sliding elements into position, and the sliding elements were used to encode data. Artificial muscles were also used to make the instruction set that the machine head uses to make decisions. In this case, when a muscle expands, it compresses a switch, causing it to conduct charge. 

In its current version, the artificial muscle computer is very large (about 1 m3) and extremely slow (0.15 Hz). However, the researchers demonstrated that it could evolve the correct sequence of calculations in response to a test input, and they predict that the computer's performance could be significantly improved. In the future, the researchers also want to investigate whether this type of computer would perform better using an analog rather than digital architecture. 

(Left) The artificial muscle computer. (Right) Sample steps for a sequence of calculations performed by the computer. Credit: O’Brien and Anderson. ©2013 American Institute of Physics

Overall, the demonstration that artificial muscles can be made to compute and "think" has implications for future prosthetics and soft robots. By sensing, computing, and moving, artificial muscles could give these devices the ability to conform to complex and uncertain environments, as well as give them reflexes like the real muscles seen in nature.

"If you look at life you see these amazing capabilities and structures," O'Brien said. "The octopus, for example, has extremely dexterous infinite-degree-of-freedom manipulators. Such manipulators would be great for our own robots, but there is the huge challenge of how to control them—the degrees of freedom can overwhelm a central controller. Octopuses solve this by distributing neurons throughout their arms. With artificial muscle logic, we might one day be able to do the same."

The researchers plan to take several steps in order to reach these goals.

"In the future we would like to miniaturize the technology to make it go faster and become more portable; develop materials that last longer before failing; make the computer entirely soft; explore analogue architectures; and build a soft robotic manipulator with a built-in computer," O'Brien said.

The researchers have also recently formed a company called Stretch Sense that makes soft wireless stretch sensors using artificial muscle technology. In the future, they hope to commercialize their artificial muscle computing as well.

More information: Benjamin Marc O'Brien and Iain Alexander Anderson. "An artificial muscle computer." Applied Physics Letters 102, 104102 (2013). DOI: 10.1063/1.4793648

Journal reference: Applied Physics Letters

Copyright 2013 Phys.org 

All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of Phys.org.

What Makes a Biophilic City?

ORIGINAL: LandArchs

by Joseph Clancy, Chief Editor & Social Media Manager

Jan 11, 2013

The second in a series of articles on biophilic design in landscape architecture, Joseph Clancy looks at what makes a city biophilic.

In my last article, I discussed the empirical evidence and case studies proving the social, health and economic benefits of biophilic design. But to what degree must a city engage in biophilia to be classed as a “biophilic city”? Timothy Beatley describes a biophilic city as being “partly defined by the qualities and biodiversity present and designed into urban life, but also the many activities and lifestyle choices and patterns, the many opportunities residents have to learn about and be engaged directly in nature, and the local institutions and commitments expressed, for instance, in local government budgets and policies”.

So how do we classify a city as a biophilic city?

Hanging Garden in CBD, Singapore

According to the works of Timothy Beatley, Biophilic Cities can be indicated by the following qualities:

Biophilic cities have abundant nature in close proximity to large numbers of urbanites

Green infrastructure programs, parklets & a high percentage land cover of green space would be steps towards fulfilling this aspect of a biophilic city. New York City qualifies as a biophilic city in this regard by PlaNYC’s goal of a public green space within a 10 minute walk of every resident by 2030, while Seattle P-Patch program aims for one community garden per 2,500 city inhabitants! 

The Highline, New York City

In biophilic cities, residents feel a deep affinity with the unique flora, fauna and fungi found there

Incentive, education and encouragement from city authorities are necessary to catalyze this goal. It measures not just the environmental values of inhabitants, but their knowledge of local and native species. In New Zealand, the city of Wellington also has over sixty community conservation groups! In the last two years alone, volunteer environmental groups have performed 28,000 hours of service on Wellington’s 4,000 hectares of nature reserves. While in Oslo, Norway, over 81% of inhabitants had visited the city’s surrounding forests in the last year, proving residents appreciation of the natural landscape.

Vitoria-Gasteiz, Salburua Restored Wetland

Wellington, New Zealand

Biophilic cities are cities that provide abundant opportunities to be outside and to enjoy nature

Urbanization causes severe fragmentation of habitats and nature, with land value at a premium, resulting in little room for green space. Well connected green spaces and green corridors can counter this problem, easing accessibility for urban inhabitants. Singapore has an extensive park system, integrated by 200-kilometers of Park Connectors, in the form of elevated walkways. Oslo, Norway is perhaps the leader in this category however, with an estimated 94% of the city’s residents living within 300 meters of a park! Anchorage, Alaska has 1 mile (1.6Km) of natural walking trails per 1,000 residents. The trails are multi use and seasonal, offering everything from hiking to skiing.

Canopy Walk, Singapore

Biophilic cities are rich multisensory environments, where the sounds of nature are as appreciated as much as the visual or ocular experience

The integration of natural spaces and ecological corridors into the urban fabric can create the conditions necessary for multisensory, nature rich environments. Implementing a Noise Reduction Plan or reducing levels of vehicular transport, would create “quiet zones”, with noise levels below 50 decibels (dB). Oslo, Norway is attempting an initiative of daylighting all eight of the city’s rivers. This will form part of the Akersleva, a combined green and blue infrastructure corridor, connecting the city centre inhabitants with nature in the very heart of the city, with 14 quiet zones planned within the corridor.

Oslo, Norway

Biophilic cities place importance on education about nature and biodiversity, and on providing many and varied opportunities to learn about and directly experience nature

Education can result in reinforcing positive feelings about nature and encouraging sustainable living among the general population. In Limerick City, Ireland, several environmental groups are working with the support of the city council to educate the city’s population on biodiversity and native wildlife species. Urban Tree Project and Limerick City Biodiversity Networkhave engaged the local population with nature, while providing guided walks, lectures and online resources to educate the city’s inhabitants on the importance of biodiversity.

Limerick City Biodiversity Network, Credit: Anthony Furlong

Biophilic cities invest in the social and physical infrastructure that helps to bring urbanites in closer connection and understanding of nature

Investment in biophilic projects is an excellent indicator of a biophilic city. Timothy Beatley identifies 5% of a cities budget dedicated to biodiversity and at least 1 current biophilic project in operation as indicative of governance in a biophilic city. Portland, Oregon, exceeds this and has invested heavily in social & green infrastructure, with Portland having the highest parks per-capita acreage in America. While Singapore’s N’Parkshave an incentive program, entitled Skyrise Greenery, for green roofs & living walls, offering up to 75% of the cost.

Tanner Springs, Portland, Oregon

Biophilic cities take steps to actively support the conservation of global nature

With cities being the epicentre of governance, innovation, employment and population, they have a necessary role in the conservation of nature on a regional, national and international scale, given their ecological footprint and negative impacts upon the environment. Such measures include; set aside of land, designation for protected sites, the creation of a biodiversity action plan and focus on compact development. In the city of Nagoya, Japan, 10% of urban land cover is set aside to be left in an unmanaged wild state as nature preserves.

While Phoenix, Arizona has taken this a step further by purchasing over 17,000 acres of natural desert for nature conservation, to help mitigate the negative effects of Phoenix’s urban sprawl. Then there is Vitoria-Gasteiz, in Basque country, encircled by a green belt to restrict encroaching development and to protect the internationally important restored wetland, the Salburua. However, the city still intends to create the Anilla Verde Interior—“the interior green belt”!

Park Olarizu, Vitoria-Gasteiz

These indicators focus on the protection, enhancement and introduction of nature into our cities, while encouraging interaction with nature by the city’s inhabitants through the process of environmental education and habitat restoration. With more than half of the world’s population living in urban centres devoid of nature, biophilic cities are no longer a choice. The benefits & criteria have been discussed, in my next article I will countdown the Top Ten Biophilic Cities.

Article written by Joseph Clancy

Science Bulletins: Shrinking Glaciers—A Chronology of Climate Change

ORIGINAL: American Museum of Natural History

Analysis of Earth's geologic record can reveal how the climate has changed over time. Scientists in New Zealand are examining samples from the rocky landscape once dominated by glaciers. They are employing a new technique called surface exposure dating, which uses chemical analysis to determine how long minerals within rocks have been exposed to the air since the glaciers around them melted. Comparisons of this data with other climate records have revealed a link between glacial retreat and rising levels of carbon dioxide in the air, findings that are informing scientists' understanding of global climate change today. 

Science Bulletins is a production of the National Center for Science Literacy, Education, and Technology (NCSLET), part of the Department of Education at the American Museum of Natural History. Find out more about Science Bulletins at http://www.amnh.org/sciencebulletins/.

Related Links

Glacier advance in southern middle-latitudes during the Antarctic Cold Reversal

http://www.nature.com/ngeo/journal/v3/n10/full/ngeo962.html

Glacier retreat in New Zealand during the Younger Dryas stadial

http://www.ncbi.nlm.nih.gov/pubmed/20829791

The Last Glacial Termination

http://www.sciencemag.org/content/328/5986/1652.full

GNS Science

http://www.gns.cri.nz/

University of Maine: Department of Earth Sciences

http://umaine.edu/earthsciences/research/

Lamont-Doherty Earth Observatory

http://www.ldeo.columbia.edu/

Columbia University: Department of Earth and Environmental Sciences

http://eesc.columbia.edu/

NZ HERALD - OUR NEW ISLAND? PUMICE FLOAT STUNS NAVY

ORIGINAL: RT

10 ago 2012 | 18:17 GMT

Video: Gigantesca masa volcánica flota a la deriva en el Pacífico La enorme masa flota sin rumbo a unos 1.000 kilómetros de Auckland (Nueva Zelanda), según informó la Marina de ese país  

Una gigantesca y extraña masa volcánica con una superficie de 26.000 kilómetros cuadrados fue avistada flotando en el océano Pacífico cerca de las costas de Nueva Zelanda. La enorme 'isla' está compuesta por una mezcla de piedra pómez y lava solidificada con multitud de burbujas de aire. Su apariencia se asemeja a una plataforma de hielo flotante y parece dirigirse a las costas neozelandesas, pero no representa un peligro para la navegación, en opinión de los expertos. "Es la cosa más extraña que he visto en 18 años en el mar", afirmó uno de los oficiales que presenció el extraño fenómeno. Los científicos atribuyen su origen a alguno de los volcanes existentes en el fondo marino. Curiosamente, se encontraron formaciones volcánicas semejantes en el mar Rojo. De hecho, como resultado de esta intensa actividad volcánica submarina, se añadió una isla más en el archipiélago de Zubair. 

Glass houses for Hermit crabs

ORIGINAL: University of Otago

Add caption

Staff at the aquarium were intrigued how hermit crabs make their homes in discarded snail shells, it was often asked “How do they manage to squeeze their entire body into such a small space?” or “Wouldn’t it be cool to see inside?”

A hermit crab at the NZMSC and Aquarium in Portobello has taken up residence in a glass shell. Just one week after the artificial shell was placed in the tank a hermit crab silently checked it out, sliding his soft abdomen in to check its delicate curves for fit. He has made it home ever since..

Enlisting the expertise of University of Otago scientific glass blower Anne Ryan, the aquarium wanted to replicate a snail shell that would be suitable home for a hermit crab. With the hermit crab taking up residence, it is now clearly visible how they twist their abdomen around the central column of the shell and the well-adapted tip of the abdomen clasps strongly to hold it in place.

Add caption

Centre Manager, Tessa Mills said “The staff are so excited. This is going to provide us with new teaching opportunities and will be really fantastic for the public to come and view.” More glass shells have been requested, so soon there may be a whole cast of hermit crabs living in glass shells at Portobello.

Photographs taken by Tomas Bird (Marine Interpreter at the NZ Marine Studies Centre)

¿Cómo lograr que los pescadores dejen de pescar en exceso?

ORIGINAL: TheEconomist

25 de febrero de 2012

De todos los muchos problemas del mar, la sobrepesca debe ser el más corregible. 

Así es como se puede hacer...

Foto: PA para The Economist

ACIDIFICACIÓN, calentamiento global, la destrucción de los arrecifes de coral: los mayores problemas que enfrenta el mar son tan amplios, profundos y aparentemente intratables como los propios océanos. Mientras el mundo no pare en reducir sus emisiones de gases de efecto invernadero, causa del calentamiento global detrás de estos problemas, ellos van a crecer. En comparación, la sobrepesca, la otra gran maldición, debería ser más fácil de corregir, sobre todo en las aguas costeras, donde la mayoría de la pesca se produce. Y sin embargo, continúa, año tras año.

Los pescadores tienen toda la razón para hacer algo. Muchas pesqueras van a toda velocidad hacia el colapso, las poblaciones de peces de gran tamaño se han reducido hasta en un 90%. Cuando las reservas están sobreexplotadas, que producen una captura menor. El costo de la mala gestión, en la pérdida de producción económica, es enorme: unos 50 millones de dólares al año, según el Banco Mundial.

Una razón por la cual el saqueo sigue es que el conocimiento de las poblaciones de peces es pobre, sobre todo en los países en desarrollo. Un nuevo intento de estadística en la estimación de los bancos restantes (ver artículo), de la Universidad de California en Santa Bárbara, por lo tanto, es bienvenida, incluso si eso no son verdad sus conclusiones, que las acciones son aún más devastadoras por lo que se pensaba. El estudio encontró que la pesca mejor entendida es más propensa a ser estable y sólida. Otra razón para la sobrepesca es la nueva tecnología (desarrollada, con acierto suficiente, para los campos de batalla), lo que hace más fácil de detectar bancos de arena. Como los barcos de gran tamaño y de refrigeración se han extendido, las flotas pesqueras han cubierto grandes distancias y arrasan con grandes capturas. Dado que la tecnología permite a los pescadores de peces operar con menos esfuerzo, explica lo rápido que las existencias se están agotando.

Los pescadores en general, comprender los riesgos de la sobrepesca. Sin embargo, todavía se ignoran las cuotas, si las hubiere. Esto es a menudo porque tienen una visión a corto plazo del activo- y que prefieren sacar provecho ahora e invertir el dinero en otra cosa. Y está, invariablemente, agravado por una sensación genralizada de despojo de bien comunes de que si no lo hacen su pillaje, otros lo harán.

En la mayoría de las pesqueras, los pescadores deberían ganar más dinero por preservar sus recursos para el largo plazo, y debe ser posible para incentivarlos a hacerlo. La mejor manera es darles derecho a una parte de los peces bien definida a largo plazo. En las pesquerías industriales reguladas, como en Islandia, Nueva Zelanda y Estados Unidos, esto ha tomado la forma de una participación negociables e individual de una cuota de pesca. Los países en desarrollo, donde la aplicación de la ley es débil, parece que les va mejor cuando un grupo tiene derechos sobre una extensión de agua se da a una flota de una cooperativa o un pueblo. El principio es el mismo: los pescadores que se sienten como propietarios son más propensos a comportarse como administradores responsables. El estudio estadístico reciente confirma que la pesca basada en derechos es generalmente más benigna.

El derecho material

Sin embargo, sólo unos pocos cientos de miles de flotas pesqueras en los océanos se comportan de esta manera, sobre todo porque estos sistemas son difíciles de establecer acertartadamente. Limitar el acceso a un recurso común crea perdedores, y por lo tanto la discordia. Las diferencias culturales afectan las tasas de éxito, no todos son tan respetuosos de la ley, como los islandeses. Casi en todas partes se necesita tiempo para convencer a los pescadores, los últimos cazadores-recolectores, a cambiar sus hábitos. Pero,  a pesar de que puede ser plagado de alertas, el enfoque basado en los derechos es el mejor disponible.

En los países ricos, las imágenes de satélite cada vez van a ayudar, haciendo el seguimiento más barato y mejor. En muchos de los pobres, la adopción a este método está en hacer que sea más fácil de formar organizaciones locales. Otra idea prometedora es la de incorporar la pesca basada en derechos, con zonas de prohibición de captura. Estos salvaguardaría las poblaciones de cría y son más fáciles de controlar que las capturas individuales. Cuando las poblaciones se empiecen a recuperar, como resultado de estas reformas, los pescadores estarán más propensos a ver las cuotas determinadas científicamente como en su propio beneficio. Al final, puede ser la única esperanza.

LAS NUBES BAJAN DE ALTURA PARA 'PROTEGER' A LA TIERRA

ORIGINAL: RT
24 feb 2012

Foto: NASA.gov

Científicos de la Universidad de Auckland, en Nueva Zelanda, confirman que en la primera década de este siglo ha disminuido la altura de las nubes en la Tierra y que este descenso podría ayudar a combatir el cambio climático.

El estudio, basado en datos de los satélites de la NASA, consistió en analizar los primeros 10 años de mediciones globales de nubes a gran altura a partir del Espectrorradiómetro multiángulo de imagen (MISR), un instrumento a bordo de la nave espacial Terra de la NASA.

De acuerdo con el informe, publicado en la revista Geophysical Research Letters, el promedio de altura de la nube global se redujo en aproximadamente un 1%,  es decir de 30 a 40 metros, entre el año 2000 y el 2010.

Roger Davies, que dirige la investigación, dijo que aunque el registro es demasiado reducido para ser definitivo, proporciona un indicio de que algo muy importante podría estar pasando.

El descenso constante en la altura de las nubes terrestres supondría la reducción de la temperatura en la superficie del planeta, lo que potencialmente ralentizaría los efectos del calentamiento global.

Esto podría representar un mecanismo de "retroalimentación negativa", un cambio causado por el calentamiento global, pero que 'trabaja' para contrarrestarlo.

Clima extremo en 2011

ORIGINAL: Green TV

Un recuento de algunos de los eventos climáticos más extremos en todo el mundo durante 2011, desde inundaciones a huracanes, tormentas de nieve y sequías.

Video es producción de  Green TV

Información climática y recuento por Vestas