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The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) brings together a consortium of international ice-sheet and climate modellers to simulate the contribution from the Greenland and Antarctic ice sheets to future sea-level rise. In this document, we describe the set-up and main results of the ISMIP6 Antarctica Tier-1 and Tier-2 experiments carried out with the ice-sheet model SICOPOLIS. The companion document for the Greenland ice sheet is available at https://doi.org/10.5281/zenodo.3971251. V1.0.1: References updated; some minor corrections. V1: Full report. V0.1: Abstract only. Funding acknowledgements: Japan Society for the Promotion of Science (JSPS) KAKENHI grant Nos. JP16H02224, JP17H06104 and JP17H06323. PalMod project (PalMod 1.1 and 1.3 with grants 01LP1502C and 01LP1504D) of the German Federal Ministry of Education and Research (BMBF).

International audience Smart buildings promise to revolutionize the way we live. Applications ranging from climate control to fire management can have significant impact on the quality and cost of these services. However, a smart building and any technology with direct effect on the safety of its occupants must undergo extensive testing. Virtual testing by means of computer simulation can significantly reduce the cost of testing and, as a result, accelerate the development of novel applications. Unfortunately, building physically-accurate simulation codes can be labor intensive. To address this problem, we propose a framework for rapid, physically-accurate virtual testing of smart building systems. The proposed framework supports analytical modeling and simulation of both a discrete distributed system as well as the physical environment that hosts it.

The objective of this paper is to examine the different ways that smallholders are brought into Fairtrade certification schemes in the Tanzanian tea industry. We examine the different ownership relations of processing factories and the percieved benefits of these different arrangements. We are looking to explore the challenges and opportunities provided by each of these different ownership relations and the possibilities for sustainability. Specifically we ask: 1) Which type of ownership arrangement is more likely to engage in Fairtrade certification? 2) Do perceived benefits from Fairtrade certification increase with the percentage of ownership shares? and 3) What aspects of these organizational relations have resulted in more sustainable relationships between growers and processors? We use descriptive qualitative analysis to identify the significance between factory ownership organization and scheme success. This also allows us to discuss participants' perceptions of the benefits of each scheme. We find that there is a movement towards innovation in the organizational strategies for linking growers to tea processing factories in Tanzania. This innovation includes new ownership arrangements of processing factories and outgrower contracts that have been associated with certified Fairtrade production. We also suggest that organizational innovation is significant for obtaining scheme success yet perceived benefits of and increased information about Fairtrade production is independent from ownership shares in processing.

We report measurements of the $e^+e^- \to B\bar{B}$, $B\bar{B}{}^*$, and $B^*\bar{B}{}^*$ cross sections at four energies, 10653, 10701, 10746 and 10805 MeV, using data collected by the Belle~II experiment. We reconstruct one $B$ meson in a large number of hadronic final states and use its momentum to identify the production process. In the first $2-5$ MeV above $B^*\bar{B}{}^*$ threshold, the $e^+e^- \to B^*\bar{B}{}^*$ cross section increases rapidly. This may indicate the presence of a pole close to the threshold. 30 pages, 15 figures, version accepted by JHEP

We report a measurement of the $e^+e^- \to π^+π^-π^0$ cross section in the energy range from 0.62 to 3.50 GeV using an initial-state radiation technique. We use an $e^+e^-$ data sample corresponding to 191 $\text{fb}^{-1}$ of integrated luminosity, collected at a center-of-mass energy at or near the $Υ{(4S)}$ resonance with the Belle II detector at the SuperKEKB collider. Signal yields are extracted by fitting the two-photon mass distribution in $e^+e^- \to π^+π^-π^0γ$ events, which involve a $π^0 \to γγ$ decay and an energetic photon radiated from the initial state. Signal efficiency corrections with an accuracy of 1.6% are obtained from several control data samples. The uncertainty on the cross section at the $ω$ and $ϕ$ resonances is dominated by the systematic uncertainty of 2.2%. The resulting cross sections in the 0.62-1.80 GeV energy range yield $ a_μ^{3π} = [48.91 \pm 0.23~(\mathrm{stat}) \pm 1.07~(\mathrm{syst})] \times 10^{-10} $ for the leading-order hadronic vacuum polarization contribution to the muon anomalous magnetic moment. This result differs by $2.5$ standard deviations from the most precise current determination. 23 pages, 24 figures, submitted to PRD

International audience; Nonlinear ultrasonic waves in solids have shown good sensitivity to quasi-static stresses. The stress sensitivity of elastic waves is typically associated to finite strains (e.g. theory of acoustoelasticity). In the case of waveguides, classical nonlinear theories for guided waves are still based on the assumption of finite strains. In the case of constrained solids subjected to thermal excursions, however, there are theoretically no finite strains (for perfectly-constrained solids) associated with thermal stresses. A new model is therefore needed to justify the existence of wave nonlinearities in this case of stress without strain. This problem is solved on the basis of the interatomic potential of the solid that indicates a Òresidualî strain energy, due to the prevented thermal expansion, that is at least cubic as a function of strain. The cubic relationship between strain energy and strain produces second-harmonic generation of propagating elastic waves. Consequently, a nonlinear wave equation can be derived. The solution to this equation leads to a new nonlinear parameter for double harmonic generation that is directly related to the thermal stresses in the structure. The present study finds applications in the monitoring of thermal stresses in buckling-prone structures, such as continuously-welded railroad tracks and pipelines.

Multiple attacker data injection attack construction in electricity grids with minimum- mean-square-error (MMSE) state estimation is studied for centralized and decentralized scenarios. A performance analysis of the trade-off between the maximum distortion that an attack can introduce and the probability of the attack being detected by the network operator is considered. Within this setting, optimal centralized attack construction strategies are studied. The decentralized case is examined in a game-theoretic setting. A novel utility function is proposed to model this trade-off and it is shown that the resulting game is a potential game. The existence and cardinality of the corresponding set of Nash Equilibria (NE) in the game is analyzed. For the particular case of two attackers, numerical results based on IEEE test systems are presented. These results suggest that attackers perform better when they seize control of power flow measurements instead of power injection measurements.