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Study: Alternate Walking and Running to Save Energy, Maintain Endurance

By Guest PostFebruary 4, 2013Healthalternate walking, best strategy, bus stop, calculation, conserve energy, data, exoskeletons, goal, human body, human energy costs, hypothesis, leroy long, less energy, maintain endurance, manoj srinivasan, marathon finish line, natural environment, notion, ohio state university, optimize energy, pam frost gorder, physical factor, prosthetic devices, running, save energy, transition region, treadmill

COLUMBUS, Ohio — Forget “slow and steady wins the race.” A new study shows that, at least sometimes, the best way to conserve energy and reach your destination on time is to alternate between walking and running—whether your goal is the bus stop or a marathon finish line.

In the January 30, 2013 issue of the Journal of the Royal Society Interface, researchers examined how people budget their time as they travel on foot to reach a destination at a particular appointed time. The study found that when people have neither too much time nor too little time to reach their destination, they naturally switch back and forth between walking and running, which turns out to be the best strategy for saving energy. (more…)

How Computers Push on the Molecules They Simulate

By Guest PostJanuary 9, 2013Scienceacceleration, albert einstein, algorithm, analytical results, artifacts, atoms and molecules, behavior, Berkeley, berkeley lab, calculation, california, california institute, chemical fuel, collide, computer method, conserve energy, david sivak, digital representation, digitize time, dna repair, driving force, effective friction, energy dense, equation, error, finite time steps, fluid, french physicist, gavin crooks, john chodera, langevin dynamics, model brownian motion, modeling molecular system, modern computer, molecular machines, molecular scale motion, molecule, momentum, natural system, nonequilibrium driving force, nonequilibrium statistical mechanics, particle, passage of time, paul langevin, photosynthesis, pollen grain, qb3, quantitative biosciences, quantum mechanics, real world, simulation, source, tenacious errors, theoretical method, thermal energy, toy models, university, velocity, water, water molecules

Berkeley Lab bioscientists and their colleagues decipher a far-reaching problem in computer simulations

Because modern computers have to depict the real world with digital representations of numbers instead of physical analogues, to simulate the continuous passage of time they have to digitize time into small slices. This kind of simulation is essential in disciplines from medical and biological research, to new materials, to fundamental considerations of quantum mechanics, and the fact that it inevitably introduces errors is an ongoing problem for scientists.

Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have now identified and characterized the source of tenacious errors and come up with a way to separate the realistic aspects of a simulation from the artifacts of the computer method. The research was done by David Sivak and his advisor Gavin Crooks in Berkeley Lab’s Physical Biosciences Division and John Chodera, a colleague at the California Institute of Quantitative Biosciences (QB3) at the University of California at Berkeley. The three report their results in Physical Review X. (more…)

Curiosity Rover Nearing Yellowknife Bay

By Guest PostDecember 14, 2012Sciencecalculation, camera, chemcam, chemistry, curiosity, curiosity traverse map, glenelg area, jet propulsion laboratory, layered martian outcrop, mars, mars rover, mast camera, mastcam, mount sharp, NASA, navcam, navigation camera, outcrop, pasadena, point lake, rick welch, rock composition, sam, sample analysis, science laboratory mission, shaler, sol 123, status report, yellowknife bay

Mars Science Laboratory Mission Status Report

PASADENA, Calif. –– The NASA Mars rover Curiosity drove 63 feet (19 meters) northeastward early Monday, Dec. 10, approaching a step down into a slightly lower area called “Yellowknife Bay,” where researchers intend to choose a rock to drill.

The drive was Curiosity’s fourth consecutive driving day since leaving a site near an outcrop called “Point Lake,” where it arrived last month. These drives totaled 260 feet (79 meters) and brought the mission’s total odometry to 0.37 mile (598 meters). (more…)

Learning About Spatial Relationships Boosts Understanding of Numbers

By Guest PostJune 18, 2012Sciencearithmetic, calculation, elizabeth gunderson, geometry, gerardo ramirez, jason smith, linear number, math problems, mathematics, number knowledge, number line, numerical representations, objects, puzzles, sian beilock, spatial learning, spatial relationships, spatial skill, stem, Technology, university of chicago

Children who are skilled in understanding how shapes fit together to make recognizable objects also have an advantage when it comes to learning the number line and solving math problems, research at the University of Chicago shows.

The work is further evidence of the value of providing young children with early opportunities in spatial learning, which contributes to their ability to mentally manipulate objects and understand spatial relationships, which are important in a wide range of tasks, including reading maps and graphs and understanding diagrams showing how to put things together. Those skills also have been shown to be important in the Science, Technology, Engineering and Mathematics (STEM) fields. (more…)

Bats Save Energy By Drawing in Wings on Upstroke

By Guest PostApril 13, 2012Nature, Scienceaerodynamics, attila bergou, bat wings, bats, brown university, calculation, calculus rich model, daniel riskin, david orenstein, flying machine, inertial energy, muscular wings, physicisist, sharon swartz, wing mass

Bat wings are like hands: meaty, bony and full of joints. A new Brown University study finds that bats take advantage of their flexibility by folding in their wings on the upstroke to save inertial energy. The research suggests that engineers looking at flapping flight should account for wing mass and consider a folding design.

PROVIDENCE, R.I. [Brown University] — Whether people are building a flying machine or nature is evolving one, there is pressure to optimize efficiency. A new analysis by biologists, physicists, and engineers at Brown University reveals the subtle but important degree to which that pressure has literally shaped the flapping wings of bats.

The team’s observations and calculations show that by flexing their wings inward to their bodies on the upstroke, bats use only 65 percent of the inertial energy they would expend if they kept their wings fully outstretched. Unlike insects, bats have heavy, muscular wings with hand-like bendable joints. The study suggests that they use their flexibility to compensate for that mass. (more…)

Tag Archives: calculation

Study: Alternate Walking and Running to Save Energy, Maintain Endurance

How Computers Push on the Molecules They Simulate

Curiosity Rover Nearing Yellowknife Bay

Learning About Spatial Relationships Boosts Understanding of Numbers

Bats Save Energy By Drawing in Wings on Upstroke