Establishing how the conformation of organic photovoltaic (OPV) polymers affects their electronic and transport properties is critical in order to determine design rules for new OPV materials and in particular to understand the performance enhancements recently reported for ternary blends. We report coupled classical and ab initio molecular dynamics simulations showing that polymer linkage twis...

FASTER is a combinatorial optimization algorithm useful for finding low-energy side-chain configurations in side-chain placement and protein design calculations. We present two simple enhancements to FASTER that together improve the computational efficiency of these calculations by as much as two orders of magnitude with no loss of accuracy. Our results highlight the importance of choosing appr...

This paper describes parallelism of image data 11sing a parallel process and developed the parallel features extraction using a morphological filter on the new generation multi-transpt~ter's network system. This system solved the limitation of communication problem in conventional transpnter networks using Inmos T9000's virtiial channnel processor and Inmos C104 packet routing switch. A morphol...

Parameters of Gaussian spatial models are often estimated using the maximum likelihood approach. In spite of its merits, this methodology is not practical for large data sets. We study the asymptotic properties of the estimators that minimize three alternatives to the likelihood function, which are meant to increase the computational efficiency. This is achieved by applying the information sand...

This paper presents two improvements to speed up the Monte-Carlo simulation of neutron noise experiments. The first one is to separate the actual Monte Carlo transport calculation from the digital signal processing routines, while the second is to introduce non-analogue techniques to improve the efficiency of the Monte Carlo calculation. For the latter method, adaptations to the theory of neutr...

Parameters of Gaussian multivariate models are often estimated using the maximum likelihood approach. In spite of its merits, this methodology is not practical when the sample size is very large, as, for example, in the case of massive georeferenced data sets. In this paper, we study the asymptotic properties of the estimators that minimize three alternatives to the likelihood function, designe...

Most high-performance organic solar cells involve bulk-heterojunctions in order to increase the active donor-acceptor interface area. The power conversion efficiency depends critically on the nano-morphology of the blend and the interface. Spectroscopy of the sub-bandgap region, i.e., below the bulk absorption of the individual components, provides unique opportunities to study interface-relate...

The accuracy and efficiency of ab initio density functional theory calculations depend critically on the choice of pseudopotential. In this study, the merits of using large-core pseudopotentials for the dissociative chemisorption of oxygen on rhodium are discussed. The results show that these efficient pseudopotentials yield adsorption energies and bond distances of the oxygen atom to rhodium t...

This paper presents an optimization design method for centrifugal compressors based on one-dimensional calculations and analyses. It consists of two parts: (1) centrifugal compressor geometry optimization based on one-dimensional calculations and (2) matching optimization of the vaned diffuser with an impeller based on the required throat area. A low pressure stage centrifugal compressor in a M...