Esoterik

Ohne Zusammenfassung „Esoterik“, im vorliegenden Sinne: einem inneren spirituellen Personenkreis vorbehaltene Lehren (unabh?ngig von ihren Inhalten)     

High-resolution biosensor spectral peak shift estimation

In this paper, we present a maximum likelihood (ML) approach to high-resolution estimation of the shifts of a spectral signal. This spectral signal arises in application of optically based resonant biosensors, where high resolution in the estimation of signal shift is synonymous with high sensitivity to biological interactions. For the particular sensor of interest, the underlying signal is nonuniformly sampled and exhibits Poisson amplitude statistics. Shift estimation accuracies orders of magnitude finer than the sample spacing are sought. The new ML-based formulation leads to a solution approach different from typical resonance shift estimation methods based on polynomial fitting and peak (or ) estimation and tracking.     

Feature-enhanced synthetic aperture radar image formation based onnonquadratic regularization

We develop a method for the formation of spotlight-mode synthetic aperture radar (SAR) images with enhanced features. The approach is based on a regularized reconstruction of the scattering field which combines a tomographic model of the SAR observation process with prior information regarding the nature of the features of interest. Compared to conventional SAR techniques, the method we propose produces images with increased resolution, reduced sidelobes, reduced speckle and easier-to-segment regions. Our technique effectively deals with the complex-valued, random-phase nature of the underlying SAR reflectivities. An efficient and robust numerical solution is achieved through extensions of half-quadratic regularization methods to the complex-valued SAR problem. We demonstrate the performance of the method on synthetic and real SAR scenes.     

Numerical Model of Sedimentation∕Thickening with Inertial Effects

A numerical model of gravity sedimentation and thickening was developed from the governing two-phase flow equations for the liquid and solid phases. The inertial and gravity terms in the solid and liquid momentum equations were retained in the gravity sedimentation and thickening model. An implicit, space-staggered finite-difference algorithm was developed for the resulting coupled partial differential equations. Constitutive relationships describing the physical properties of the slurry were required to solve the numerical model. These constitutive properties describing the relationship between effective stress and porosity and between permeability and porosity were determined experimentally and by model calibration. The model was calibrated and verified using the data of dynamic porosity profiles of gravity sedimentation and thickening of kaolin suspensions in distilled water.     

Scenarios for the Austrian food chain in 2020 and its landscape impacts

How the future landscape will look depends particularly on the outcome of the socio-economically motivated decisions of farmers, food processors, retailers and consumers, all members of the food supply chain. However, a long-term perspective on the food supply chain and its landscape effects is confronted with a great deal of uncertainty and data constraints. These difficulties can be partly avoided by using the personal judgements of agents whose decisions control the structure of present and future food supply chains. A well-established agent-based method for dealing with and describing variation in the future is the method of scenario planning. The aim of this paper is to present the application of the scenario approach to the Austrian food supply chain in 2020 and its landscape impacts. A critical discussion of the scenarios should reflect their explanatory power regarding future development options for landscapes. The first section of the paper outlines the interactions between society, the food supply chain and the landscape in a conceptual model. It describes the applied scenario technique and the research setting involving agents from agriculture, the food industry, retailing, gastronomy, and consumer organisations. Four scenarios for the food chain in 2020 are presented (Liberal Market Scenario, Protective Policy Scenario, Fast World Scenario, Slow World Scenario) and their respective consequences and strategies are discussed. The scenario technique used is found to be a useful means of gathering and structuring disperse expert knowledge. The paper concludes that—despite some methodological limitations—scenarios can deal with uncertainty concerning the socio-economic driving forces of landscape change and therefore can be used as a preliminary step in formulating robust strategies for landscape management.     

Optical frequency standards and measurements

We describe the performance characteristics and frequency measurements of two high-accuracy high-stability laser-cooled atomic frequency standards. One is a 657-nm (456-THz) reference using magneto-optically trapped Ca atoms, and the other is a 282-nm (1064-THz) reference based on a single Hg⁺ ion confined in an RF-Paul trap. A femtosecond mode-locked laser combined with a nonlinear microstructure fiber produces a broad and stable comb of optical modes that is used to measure the frequencies of the reference lasers locked to the atomic standards. The measurement system is referenced to the primary frequency standard NIST F-1, a Cs atomic fountain clock. Both optical standards demonstrate exceptional short-term instability (≈5×10^-15 at 1 s), as well as excellent reproducibility over time. In light of our expectations for the future of optical frequency standards, we consider the present performance of the femtosecond optical frequency comb, along with its limitations and future requirements