The Random Phase Approximation (RPA), which represents the fifth rung of accuracy in Density Functional Theory (DFT), is made practical for large systems. Energies of condensed phase systems containing 1000s of explicitly correlated electrons and 1500 atoms can now be computed in minutes and less than one hour, respectively. GPU acceleration is employed for dense and sparse linear algebra, while communication is minimized by a judicious data layout. The performance of the algorithms, implemented in the widely used CP2K simulation package, has been investigated on hybrid Cray XC30 and XK7 architectures, up to 16384 nodes. Our results emphasize the importance of good network performance, in addition to the availability of GPUs and generous on node memory. A new level of predictivity has thus become available for routine application in Monte Carlo and molecular dynamics simulations.

Acoustical quality of the indoor environment is increasingly being recognized as important in commercial, residential and institutional building design. Unwanted sound is the most prevalent annoyance in many modern structures, leading to increased stress, loss of productivity and decreased quality of life for building occupants. The authors propose a minimum LEED standard for acoustical quality which can be incorporated into initial design or employed as a post-construction evaluation tool.

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The cost of energy is a significant percentage of the operating expense for most buildings. Energy used within buildings is supplied primarily by electricity. Demand for electricity used in industrial and agricultural applications is frequently leveled by shifting portions of peak loads to non-peak periods. Leveling electrical loads reduces the utility's carbon footprint and the cost of generating power. Resulting savings are commonly shared with customers through economic incentives. Similar techniques can be applied to control the energy demand of buildings, with benefits for both the electrical utility and electricity users. This paper provides an overview of electrical load-shedding techniques, outlines some of the benefits and problems associated with each, and discusses how some of these techniques are currently being applied to reduce the total electrical load for buildings. The paper also proposes a LEED credit which provides an incentive for owners and tenants to incorporate one or more load-shedding systems into LEED certified buildings to lower peak electrical demand.