Adaptive Response for Exponential Smoothing: Comparative System Analysis

In effectively applying general exponential smoothing, a central requirement is the use of a proper parameter-a proper rate of discounting past information. Since a single value for the parameter is inefficient under varying demand conditions, several methods to adjust the parameter adaptively have been developed. This paper contains an analysis and comparison of these methods.     

Quantum-to-classical crossover in full counting statistics

The reduction of quantum scattering leads to the suppression of shot noise. In this Letter, we analyze the crossover from the quantum transport regime with universal shot noise to the classical regime where noise vanishes. By making use of the stochastic path integral approach, we find the statistics of transport and the transmission properties of a chaotic cavity as a function of a system parameter controlling the crossover. We identify three different scenarios of the crossover.     

Structural order for one-scale and two-scale potentials

We perform molecular dynamics simulations to investigate the relationship between structural order and waterlike dynamic and thermodynamic anomalies in spherically symmetric potentials having either one or two characteristic length scales. Structural order is characterized by translational and orientational order parameters. We find that (i) dynamic and thermodynamic anomalies exist for both one-scale and two-scale ramp potentials, and (ii) waterlike structural order anomalies exist only for the two-scale ramp potential. Our findings suggest that the waterlike relationship between structural order and anomalies is related to the presence of two different length scales in the potential.     

Glass-transition temperature of water: a simulation study

We report a computer simulation study of the glass transition for water using the extended simple point charge potential. To mimic the difference between standard and hyperquenched glass, we generate glassy configurations with different cooling rates, and we calculate the temperature dependence of the specific heat on heating. The absence of crystallization phenomena allows us, for properly annealed samples, to detect in the specific heat the simultaneous presence of a weak prepeak ("shadow transition") and an intense glass transition peak at higher temperature. Our results support the view-point that the glass transition temperature is higher than the conventionally accepted value 136 K. We also compare our simulation results with the Tool-Narayanaswamy-Moynihan phenomenological model.     

A Two Dimensional Fermi Liquid. Part 2: Convergence

Using results established in other papers in our series, we prove the existence of the infinite volume, temperature zero, thermodynamic Greens functions of a two dimensional, weakly coupled fermion gas with an asymmetric Fermi curve and short range interactions. This is done by showing that our sequence of renormalization group maps converges.Research supported in part by the Natural Sciences and Engineering Research Council of Canada and the Forschunginstitut für Mathematik, ETH Zürich.     

The Effect of Pea Chloroplast Alignment and Variation of Excitation Wavelength on the Circularly Polarized Chlorophyll Luminescence

Circularly polarized luminescence (CPL) is a powerful technique to study the macroorganization of photosynthetic light-harvesting apparatus in vivo and in vitro. It is particularly useful for monitoring environmental stress induced molecular re-organization of thylakoid membranes in green leaves. The current study focuses on two questions which are important to perform and interpret such experiments: how does CPL depend on the excitation wavelength and how on the orientation of the granal thylakoids. CPL and circular dichroism (CD) of pea chloroplasts were complementarily applied when chloroplasts were either in suspension or trapped in a polyacrylamide gel (PAAG) after alignment in a magnetic field. In contrast to the CD spectrum, the CPL signal was found to be independent of the excitation wavelength in both the Soret and the Qy absorption region for chloroplasts in both suspension and PAAG. The improved resolution of luminescence measurements revealed a relatively small negative CPL band in addition to the previously described large positive band. No effect of photoselection upon excitation on the CPL spectra was detected. The CPL intensity at 690 nm at the edge of the granal thylakoids was found to be higher than at the face of the grana suggesting the CPL anisotropy.