Complexity Digest 2001.33

13-Aug-2001

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Content

  1. Control Technique Cuts Electricity Bills For Commercial Buildings, Purdue Univ/ScienceDaily
  2. Robots Beat Human Commodity Traders, New Scientist
    1. Still Waiting on Neural Nets, Technology Review
  3. Fire's Spread Looks Fractal, Nature
  4. Avoiding Ambiguity, Nature
  5. Time Of Growing Pains For Information Age, NYTimes
  6. Origin Of The Patents, Technology Review
  7. Computer Program Raises Possibility Of Voice Theft, New Scientist
    1. Gadget Puts Words In Dog's Mouth, New Scientist
  8. Left In Music, Nature
  9. Quantum Memories Should Mimic Ours, Nature
  10. Mathematics of Philosophy or Philosophy of Mathematics? Nonlin Dyn, Psych. & Life Sciences
  11. Jigsaw Model Of The Origin Of Life, Proceedings of SPIE
  12. Designer Molecules Can Be Made To Follow Orders, Researcher Says, SmallTimes
  13. Analysis Of Complex Brain Disorders With Gene Expression Microarrays, Trends Neurosci
  14. Design By Numbers, Nature
  15. Molecular Electronics: Momentous Period For Nanotubes, Nature
  16. Solar Cell Organization, Science
    1. Solar Cells by Self-Assembly?, Science
    2. Self-Organized Discotic Liquid Crystals for High-Efficiency Organic Photovoltaics, Science
    3. "Self-Assembling" Solar Cells Developed, New Scientist
  17. Send In The Clouds, The Christian Science Monitor
  18. Numeric Simulation of Plant Signaling Networks, Plant Physiol.
  19. Book Report: An Energetic View Of Nature
  20. Links & Snippets
    1. Other Articles
    2. Announcements

  1. Control Technique Cuts Electricity Bills For Commercial Buildings, Purdue Univ/ScienceDaily Next Article Bookmark and Share

    Excerpt: Research engineers have shown that electricity costs for office buildings can be reduced by up to 40 percent by running air conditioning overnight.

    "Pre-cooling" structures so that it takes less power to cool buildings during times of peak demand is not a new technique. But engineers at Purdue University are the first researchers to create a computer-simulation tool that can be "tuned" to a specific building and used to document the savings that would be realized by using the technique for that specific building. The analysis tool takes into account factors including utility rates and climate, and it can be used to tailor the best pre-cooling strategy for individual buildings.

    The pre-cooling technique is especially practical in areas where utility companies are having trouble meeting demands for electricity. In those areas, the price for daytime electricity is much higher than the price charged overnight.

    The tool was tested on a four-floor, 1.4 million-square-foot Ameritech Corp. office building in the Chicago-area suburb of Hoffman Estates, Ill. The simulation showed that a pre-cooling technique could reduce electricity costs by as much as 41 percent during the hottest summer months.


  2. Robots Beat Human Commodity Traders, New Scientist Next Article Bookmark and Share

    Excerpts: In IBM's test, software-based robotic trading agents - known as "bots" - made seven per cent more cash than people. Both bots and people had the same set-up, allowing them to trade through an unbiased software-based auctioneer. The auction was designed to mimic the kind of commodities market where buyers and sellers have a fixed amount of time to trade in a single commodity.

    Six bots and six people traded against each other. (...). Their goal was to maximize their profit at the end of trading.


    1. Still Waiting on Neural Nets, Technology Review Next Article Bookmark and Share

      Excerpts: The promise of artificial neural networks is the stuff of sci-fi movies: computers that learn and work much like humans-through experience.

      In the real world, however, neural networks haven't begun to live up to their potential. It appears that human nature is at least partially standing in the way-with a failure to communicate fully between two key groups.

      Researchers gathered to discuss real-world applications of neural networks at a session of the International Joint Conference on Neural Networks held in Washington, DC, in July.


  3. Fire's Spread Looks Fractal, Nature Next Article Bookmark and Share

    Excerpts: Fire-fighting should focus on the most recently ignited sites, suggests a new mathematical model. (...) the boundaries where a forest fire is growing fastest are more dangerous than the rest. (...)

    The fire images looked like loose aggregates of particles, with ragged, branched edges and unburnt 'islands' inside the perimeters. The shapes of the advancing fire front and burnt regions don't completely fill the two-dimensional space inside their apparent borders, but have gaps and islands of all sizes.


  4. Avoiding Ambiguity, Nature Next Article Bookmark and Share

    Excerpt: There are a number of reasons why the language of mathematics may not always provide much insight into a complex reality. (...) assumptions can creep in unawares. This is particularly true when a previously useful mathematical model is retailored to fit a new crisis. It is rather easy in these circumstances to become trapped in, and even comforted by, a prevailing paradigm. It is unfortunate that the assumptions embedded in the mathematical structures employed may not always be obvious to the general public.

  5. Time Of Growing Pains For Information Age, NYTimes Next Article Bookmark and Share

    Excerpts: One difficulty, Dr. Smolin and the others pointed out, is that a simple program can give a complex result. (...)

    Another example, maintained Dr. Pollack, is life itself, which, he pointed out had begun billions of years ago as a pool of random chemicals, running its own "simple program" and baking in the sun. (...)

    Living organisms today are made of a relatively few number of genes and amino acids, but that is the result of billions of years of evolution in nature's computer.


  6. Origin Of The Patents, Technology Review Next Article Bookmark and Share

    Excerpts: Now reinventing recent patents, genetic programming heads toward automated "invention machines." (...)

    At Stanford, genetic programming research seeks to produce results that are competitive with human problem solving, and to test that by evaluating success in duplicating or infringing upon existing U.S. patents. The research effort now has accomplished just that for patents generated as recently as last year. The work may eventually deliver automated "invention machines," says John Koza, genetic computing guru and consulting professor of biomedical informatics at Stanford.


  7. Computer Program Raises Possibility Of Voice Theft, New Scientist Next Article Bookmark and Share

    Excerpts: The program, developed by a team at AT&T Laboratories in the US, convincingly mimics a particular voice by reconstructing its individual nuances and intonations from pre-recordings. (...)

    Creating each new synthesized voice requires between 10 and 40 hours of studio recordings of the person speaking (...). Nevertheless, the experts who built the program believe that within a few years, it could create a perfect copy of someone's voice. (...)

    AT&T has spun off a company, called Natural Voices, to market the voice copying system.


    1. Gadget Puts Words In Dog's Mouth, New Scientist Next Article Bookmark and Share

      Excerpt: A gadget that analyses a dog's whines and growls and translates them into words will be launched next year.

      The "Bow-lingual", developed by Japanese toy manufacturer Takara Co. Ltd, consists of a six-centimetre dog collar microphone that transmits sounds to a palm-sized console. The console uses 200 different words, including "fun", "boring" and "happy", to translate six basic dog "emotions" in real time.

      A series of similar words automatically produces sentences such as "Please, please, if you don't listen to me, I'll sulk."


  8. Left In Music, Nature Next Article Bookmark and Share

    Excerpt: Professional musicians use their left brain more than other people when listening to music, a magnetic-resonance study suggests. Musicians, unlike others, may process music much as a language, the result hints.

    When played a recording of Bach's Italian Concerto , all the study's 28 subjects showed activity in the planum temporale, part of the temporal lobe above the ear canal that is thought to be responsible for many auditory tasks. Non-musicians' brain activity was concentrated in the right side of the planum temporale, but in musicians the left side dominated.

    • Left In Music, Erica Klarreich, Nature Science Update, 01/08/13


  9. Quantum Memories Should Mimic Ours, Nature Next Article Bookmark and Share

    Excerpts: Quantum memories, Trugenberger suggests1, could be associative (...). He shows that, even if the input to such a device is noisy or incomplete, the most probable output is the one that most closely resembles ('overlaps') the input.

    Some scientists have suggested that the brain's uncanny ability to recall patterns such as faces and scenes implies that it already is a kind of quantum computer.

    (...) being able to hold all the elements of the memorized pattern in an entangled superposition of states


  10. Mathematics of Philosophy or Philosophy of Mathematics? Nonlin Dyn, Psych. & Life Sciences Next Article Bookmark and Share

    Abstract: This article examines recent attempts to gain insight into philosophical paradoxes through using NDS models employing iterated difference equations and resulting phase portraits and escape time diagrams. The temporal nature of such models is contrasted with an alternative approach based on the a-temporal and non-dynamical construct of a lattice. Finally, there is a discussion of how such strategies for understanding paradox transcend the realm of empirical research and enter territory in the philosophy of mathematics.

  11. Jigsaw Model Of The Origin Of Life, Proceedings of SPIE Next Article Bookmark and Share

    Abstract: It is suggested that life originated in a three-step process referred to as the jigsaw model. RNA, proteins, or similar organic molecules polymerized in a dehydrated carbon-rich environment, on surfaces in a carbon-rich environment, or in another environment where polymerization occurs. These polymers subsequently entered an aqueous environment where they folded into compact structures. It is argued that the folding of randomly generated polymers such as RNA or proteins in water tends to partition the folded polymer into domains with hydrophobic cores and matching shapes to minimize energy. In the aqueous environment, hydrolysis or other reactions fragmented the compact structures into two or more matching molecules, occasionally producing simple living systems, also known as autocatalytic sets of molecules. It is argued that the hydrolysis of folded polymers such as RNA or proteins is not random. The hydrophobic cores of the domains are rarely bisected due to the energy requirements in water. Hydrolysis preferentially fragments the folded polymers into pieces with complementary structures and chemical affinities.

    Thus the probability of producing a system of matched, interacting molecules in prebiotic chemistry is much higher than usually estimated. Environments where this process may occur are identified. For example, the jigsaw model suggests life may have originated at a seep of carbonaceous fluids beneath the ocean. The polymerization occurred beneath the sea floor.

    The folding and fragmentation occurred in the ocean. The implications of this hypothesis for seeking life or prebiotic chemistry in the Solar System are explored.

    • Jigsaw Model Of The Origin Of Life, John F. McGowan, III, in Instruments,Methods, Missions for Astrobiology IV, Richard B. Hoover, Editor, Proceedings of SPIE (Society of Photo-Optical Instrumentation Engineers) Vol. 4495, (2001)
    • Constributed by the author

  12. Designer Molecules Can Be Made To Follow Orders, Researcher Says, SmallTimes Next Article Bookmark and Share

    Excerpts: To develop the self-assembling structures, Fenniri and his colleagues borrowed chemistry from DNA to create a series of molecules that are "programmed" to link in groups of six to form rosette-shaped rings, which then combine to form rod-like structures, or nanotubes. (...)

    "(...) Created from elements that normally bind together, the molecule recognizes and wants to mate with itself. The molecule's attempts to make order out of its confusion help spark the selfassembly process, allowing the molecules to form rings and tubes without intervention," he adds.


  13. Analysis Of Complex Brain Disorders With Gene Expression Microarrays, Trends Neurosci Next Article Bookmark and Share

    Abstract: The level of cellular and molecular complexity of the nervous system creates unique problems for the neuroscientist in the design and implementation of functional genomic studies. Microarray technologies can be powerful, with limitations, when applied to the analysis of human brain disorders. Recently, using cDNA microarrays, altered gene expression patterns between subjects with schizophrenia and controls were shown. Functional data mining led to two novel discoveries: a consistent decrease in the group of transcripts encoding proteins that regulate presynaptic function; and the most changed gene, which has never been previously associated with schizophrenia, regulator of G-protein signaling 4. From these and other findings, a hypothesis has been formulated to suggest that schizophrenia is a disease of the synapse. In the context of a neurodevelopmental model, it is proposed that impaired mechanics of synaptic transmission in specific neural circuits during childhood and adolescence ultimately results in altered synapse formation or pruning, or both, which manifest in the clinical onset of the disease.

  14. Design By Numbers, Nature Next Article Bookmark and Share

    Excerpts: Many biologists' concerns about optimization theory seem to stem from a classic paper by Stephen Jay Gould and Richard Lewontin. These authors pointed out that, because evolution is constrained by ancestry, only local optima may be accessible, as in my example of the squid. (...) The value to biology of properly applied optimization theory has been splendidly demonstrated by Geoffrey Parker and John Maynard Smith, but their message may have to be repeated many times before the doubters are convinced.

  15. Molecular Electronics: Momentous Period For Nanotubes, Nature Next Article Bookmark and Share

    Excerpts: When conductors are reduced to molecular dimensions they can develop exotic properties. Physicists have now directly confirmed unusual electron behavior in carbon nanotubes. (...)

    An obstacle to using nanotubes as electronic wires is that the conducting electrons sometimes reflect backwards, by bouncing off a structural defect in the tube or off a smoother variation in electrical potential. (...) Together, these properties suggest that nanotubes may soon be able to conduct electrons over many micrometres, making them a viable, much smaller alternative to conventional electronic wires.


  16. Solar Cell Organization, Science Next Article Bookmark and Share

    Excerpts: Summary In organic solar cells, absorbed photons create charge carriers (electrons and "holes") that are taken up by n- and p-type materials that send them to the electrodes. The efficiency of the cell will depend on how closely the n- and p-type materials can be brought into contact. Schmidt-Mende et al. (p. 1119; see the Perspective by Nelson) have developed a simple solution-based process in which self-organization creates a nanoscale interface in the organic layer. The hole-accepting material is incorporated as a discotic liquid crystal, which creates columnar structures within the film that are surrounded by an electron-accepting organic dye. This structure leads to efficient charge separation of carriers between the discotic material and the dye.

    1. Solar Cells by Self-Assembly?, Science Next Article Bookmark and Share

      Excerpts: In the quest for solar cells that are flexible, ultrathin, and cost-efficient, molecular solids are emerging as strong contenders. Soluble light-emitting molecular solids are already used in display applications. Solar cells made from such materials could benefit from low-tech, large-volume production techniques, greatly reducing their production cost relative to crystalline photovoltaic materials.

      But molecular-solid-based devices have long suffered from low efficiencies. (...) Schmidt-Mende et al.

      report a photovoltaic device (...) that partially overcomes these problems. The very simple device converts visible photons to electrons with impressive efficiency.


    2. Self-Organized Discotic Liquid Crystals for High-Efficiency Organic Photovoltaics, Science Next Article Bookmark and Share

      Excerpts: Self-organization of liquid crystalline and crystalline-conjugated materials has been used to create, directly from solution, thin films with structures optimized for use in photodiodes. (...) When incorporated into diode structures, these films show photovoltaic response with external quantum efficiencies of more than 34 percent near 490 nanometers. These efficiencies result from efficient photoinduced charge transfer (...). This development demonstrates that complex structures can be engineered from novel materials by means of simple solution-processing steps and may enable inexpensive, high-performance, thin-film photovoltaic technology.


    3. "Self-Assembling" Solar Cells Developed, New Scientist Next Article Bookmark and Share

      Excerpt: Solar cells that "self assemble" from a liquid have been developed by scientists at the University of Cambridge. The breakthrough could make it cheap and easy to cover large areas, like roofs, with efficient, ultra-thin solar cell coatings.

      "This is potentially very important," says Jenny Nelson, an expert in solar cells at Imperial College in London. "If you've got something in solution, you could, in principle, put down very large areas of photo-voltaic material very cheaply."


  17. Send In The Clouds, The Christian Science Monitor Next Article Bookmark and Share

    Excerpt: During the summer of 1976, a dozen years before climate change burst on the scene as a hot-button issue, climate scientist Bruce Wielicki saw the future, and it was in clouds. (...) At one point, (...) he teamed up with a climate modeler studying how the Earth and atmosphere balance the energy they receive from the sun. Wielicki had been working on a simple computer model to simulate the effect changing sea-surface temperatures have on climate, including cloudiness. The two decided to see what would happen if they linked their models. (...)
    • Send In The Clouds, Peter N. Spotts, The Christian Science Monitor, 7/12/01
    • Contributed by Mason Porter

  18. Numeric Simulation of Plant Signaling Networks, Plant Physiol. Next Article Bookmark and Share

    Abstract: Plants have evolved an intricate signaling apparatus that integrates relevant information and allows an optimal response to environmental conditions. For instance, the coordination of defense responses against pathogens involves sophisticated molecular detection and communication systems. Multiple protection strategies may be deployed differentially by the plant according to the nature of the invading organism. These responses are also influenced by the environment, metabolism, and developmental stage of the plant. Though the cellular signaling processes traditionally have been described as linear sequences of events, it is now evident that they may be represented more accurately as network-like structures. The emerging paradigm can be represented readily with the use of Boolean language. This digital (numeric) formalism allows an accurate qualitative description of the signal transduction processes, and a dynamic representation through computer simulation. Moreover, it provides the required power to process the increasing amount of information emerging from the fields of genomics and proteomics, and from the use of new technologies such as microarray analysis. In this review, we have used the Boolean language to represent and analyze part of the signaling network of disease resistance in Arabidopsis.

  19. Book Report: An Energetic View Of Nature Next Article Bookmark and Share

    Excerpt: In Cosmic Evolution he examines the central question of why we are here, taking as the background the present understanding of our cosmological context. His intention is "to sketch a grand evolutionary synthesis that would better enable us to understand who we are, whence we came, and how we fit into the overall scheme of things". He focuses on the origins of structure and the spontaneous rise of complexity in nature, in particular, biological life and human intelligence.

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