Greenhouse gas emissions from agriculture in the EU: A spatial assessment of sources and abatement costs

Agriculture contributes significantly to the emissions of greenhouse gases in the EU. By using a farm-type, linear-programming based model of the European agricultural supply, we first assess the initial levels of methane and nitrous oxide emissions at the regional level in the EU. For a range of CO2 prices, we assess the potential abatement that can be achieved through an IPCC-based emission tax in EU agriculture, as well as the resulting optimal mix of emission sources in the total abatement. Further, we show that the spatial variability of the abatement actually achieved at a given carbon price is large, indicating that abatement cost heterogeneity is a fundamental feature in the design of a mitigation policy. We assess the efficiency loss associated with uniform standards relative to an emission tax.Climate change, greenhouse gas emissions, agriculture, methane, nitrous oxide, European Union, marginal abatement costs, Environmental Economics and Policy, Q25, Q15,

AUTOMATED MODEL-BASED REORGANIZATION OF SPEECH-TO-TEXT TRANSCRIPTS

Techniques are presented herein that support the automated reorganization of a meeting transcript. According to the presented techniques, when a meeting is recorded it is first transcribed through an automated speech-to-text system. Then, the resulting raw document is decomposed into sections corresponding to different topics, the topics are reorganized into a more coherent and intelligible structure, and missing pieces of information may be identified and then added to the document. Such postprocessing increases the intelligibility and value of meeting transcriptions and ensures that they remain understandable and useful over the long term. Aspects of the presented techniques may leverage large language models (LLMs) and automatic speech recognition (ASR) capabilities

Rapid assembly of highly-functionalised difluorinated cyclooctenones via ring-closing metathesis

Building block methodology from trifluoroethanol and ringclosing metathesis using a Fürstner modification of Grubbs’ conditions allows the rapid synthesis of novel difluorinated cyclooctenones

Nonlinear Rotor Wake/Stator Interaction Computations

Rotor wake interactions with stators is an important aspect in turbomachinery noise generation. This paper deals with the time lagged periodic boundary condition (chorochronic periodicity) used in time domain Navier-Stokes equations solvers. The time lag periodic b.c. is used to solve the nonlinear three dimensional N-S equations using realizable k-epsilon turbulence model and time dependent wake defined at the inlet, with only a limited number of blade passages discretized. The time lag periodic b.c. has been validated through a number of 3D test cases. It has been shown that the use of a periodic/temporal damping term is an efficient way to stabilize the time lagged boundary condition without adding any extra spatial dissipation to the computation. The acoustic response from a stator vane with wakes defined at the inlet is presented

Investigating the Effect of Recruitment Variability on Length-Based Recruitment Indices for Antarctic Krill Using an Individual-Based Population Dynamics Model

Antarctic krill (Euphausia superba; herein krill) is monitored as part of an on-going fisheries observer program that collects length-frequency data. A krill feedback management programme is currently being developed, and as part of this development, the utility of data-derived indices describing population level processes is being assessed. To date, however, little work has been carried out on the selection of optimum recruitment indices and it has not been possible to assess the performance of length-based recruitment indices across a range of recruitment variability. Neither has there been an assessment of uncertainty in the relationship between an index and the actual level of recruitment. Thus, until now, it has not been possible to take into account recruitment index uncertainty in krill stock management or when investigating relationships between recruitment and environmental drivers. Using length-frequency samples from a simulated population - where recruitment is known - the performance of six potential length-based recruitment indices is assessed, by exploring the index-to-recruitment relationship under increasing levels of recruitment variability (from +/- 10% to +/- 100% around a mean annual recruitment). The annual minimum of the proportion of individuals smaller than 40 mm (F40 min, %) was selected because it had the most robust index-to-recruitment relationship across differing levels of recruitment variability. The relationship was curvilinear and best described by a power law. Model uncertainty was described using the 95% prediction intervals, which were used to calculate coverage probabilities and assess model performance. Despite being the optimum recruitment index, the performance of F40 min degraded under high (\u3e50%) recruitment variability. Due to the persistence of cohorts in the population over several years, the inclusion of F40 min values from preceding years in the relationship used to estimate recruitment in a given year improved its accuracy (mean bias reduction of 8.3% when including three F40 min values under a recruitment variability of 60%)

GaN directional couplers for integrated quantum photonics

Large cross-section GaN waveguides are proposed as a suitable architecture to achieve integrated quantum photonic circuits. Directional couplers with this geometry have been designed with aid of the beam propagation method and fabricated using inductively coupled plasma etching. Scanning electron microscopy inspection shows high quality facets for end coupling and a well defined gap between rib pairs in the coupling region. Optical characterization at 800 nm shows single-mode operation and coupling-length-dependent splitting ratios. Two photon interference of degenerate photon pairs has been observed in the directional coupler by measurement of the Hong-Ou-Mandel dip with 96% visibility.Comment: 4 pages, 5 figure