The Guy at the Controls: Labor Quality and Power Plant Efficiency

This paper examines the impact of individual human operators on the fuel efficiency of power plants. Although electricity generation is a fuel and capital intensive enterprise, anecdotal evidence, interviews, and empirical analysis support the hypothesis that labor, particularly power plant operators, can have a non-trivial impact on the operating efficiency of the plant. We present evidence to demonstrate these effects and survey the policies and practices of electricity producing firms that either reduce or exacerbate fuel efficiency differences across individual plant operators.

Effect of nuclear interactions of neutral kaons on CP asymmetry measurements

We examine the effect of the difference in nuclear interactions of ${K}^0$ and $\bar{K}^0$ mesons on the measurement of CP asymmetry for experiments at $e^+e^-$ colliders - charm and $B$-meson factories. We find that this effect on CP asymmetry can be as large as 0.3%, and therefore sufficiently significant in interpreting measurements of CP asymmetry when neutral kaons are present in the final state.Comment: accepted to PR

Optimal Exploitation of the Sentinel-2 Spectral Capabilities for Crop Leaf Area Index Mapping

The continuously increasing demand of accurate quantitative high quality information on land surface properties will be faced by a new generation of environmental Earth observation (EO) missions. One current example, associated with a high potential to contribute to those demands, is the multi-spectral ESA Sentinel-2 (S2) system. The present study focuses on the evaluation of spectral information content needed for crop leaf area index (LAI) mapping in view of the future sensors. Data from a field campaign were used to determine the optimal spectral sampling from available S2 bands applying inversion of a radiative transfer model (PROSAIL) with look-up table (LUT) and artificial neural network (ANN) approaches. Overall LAI estimation performance of the proposed LUT approach (LUTN₅₀) was comparable in terms of retrieval performances with a tested and approved ANN method. Employing seven- and eight-band combinations, the LUTN₅₀ approach obtained LAI RMSE of 0.53 and normalized LAI RMSE of 0.12, which was comparable to the results of the ANN. However, the LUTN50 method showed a higher robustness and insensitivity to different band settings. Most frequently selected wavebands were located in near infrared and red edge spectral regions. In conclusion, our results emphasize the potential benefits of the Sentinel-2 mission for agricultural applications

Ergodic and Nonergodic Anomalous Diffusion in Coupled Stochastic Processes

Inspired by problems in biochemical kinetics, we study statistical properties of an overdamped Langevin process whose friction coefficient depends on the state of a similar, unobserved process. Integrating out the latter, we derive the long time behaviour of the mean square displacement. Anomalous diffusion is found. Since the diffusion exponent can not be predicted using a simple scaling argument, anomalous scaling appears as well. We also find that the coupling can lead to ergodic or non-ergodic behaviour of the studied process. We compare our theoretical predictions with numerical simulations and find an excellent agreement. The findings caution against treating biochemical systems coupled with unobserved dynamical degrees of freedom by means of standard, diffusive Langevin descriptions

Band Gap and Edge Engineering via Ferroic Distortion and Anisotropic Strain: The Case of SrTiO3_{3}

The effects of ferroic distortion and biaxial strain on the band gap and band edges of SrTiO$_{3}$ (STO) are calculated using density functional theory and many-body perturbation theory. Anisotropic strains are shown to reduce the gap by breaking degeneracies at the band edges. Ferroic distortions are shown to widen the gap by allowing new band edge orbital mixings. Compressive biaxial strains raise band edge energies, while tensile strains lower them. To reduce the STO gap, one must lower the symmetry from cubic while suppressing ferroic distortions. Our calculations indicate that for engineered orientation of the growth direction along [111], the STO gap can be controllably and considerably reduced at room temperature.Comment: 5 pages, 5 figures. To be published in Phys. Rev. Let

Enforcement of vintage differentiated regulations: the case of New Source Review

This paper analyzes the effects of the New Source Review (NSR) environmental regulations on coal-fired electric power plants. Regulations that grew out of the Clean Air Act of 1970 required new electric generating plants to install costly pollution control equipment but exempted existing plants. Existing plants lost their exemptions if they made major modifications. We examine whether this caused firms to invest less in grandfathered plants, possibly leading to lower efficiency and higher emissions. We find evidence that heightened NSR enforcement reduced capital expenditures at vulnerable plants. However, we find no discernable effect on other inputs or emissions. This paper analyzes the effects of the New Source Review (NSR) environmental regulations on coal-fired electric power plants. Regulations that grew out of the Clean Air Act of 1970 required new electric generating plants to install costly pollution control equipment but exempted existing plants. Existing plants lost their exemptions if they made major modifications. We examine whether this caused firms to invest less in grandfathered plants, possibly leading to lower efficiency and higher emissions. We find evidence that heightened NSR enforcement reduced capital expenditures at vulnerable plants. However, we find no discernable effect on other inputs or emissions

Boolean networks with reliable dynamics

We investigated the properties of Boolean networks that follow a given reliable trajectory in state space. A reliable trajectory is defined as a sequence of states which is independent of the order in which the nodes are updated. We explored numerically the topology, the update functions, and the state space structure of these networks, which we constructed using a minimum number of links and the simplest update functions. We found that the clustering coefficient is larger than in random networks, and that the probability distribution of three-node motifs is similar to that found in gene regulation networks. Among the update functions, only a subset of all possible functions occur, and they can be classified according to their probability. More homogeneous functions occur more often, leading to a dominance of canalyzing functions. Finally, we studied the entire state space of the networks. We observed that with increasing systems size, fixed points become more dominant, moving the networks close to the frozen phase.Comment: 11 Pages, 15 figure