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During last years, the Palermo Aike (or Inoceramus) shale formation, in the Austral Basin of Argentina, has received increasing attention from both the oil industry and academia. Due to the intrinsic elastic anisotropy observed in this kind of rocks, vertical well logs are not enough to characterize properly the formation. For this reason, we propose to combine standard well logs and laboratory data measured on drill cuttings to estimate the whole stiffness tensor and the characteristic anisotropy coefficients at borehole scale. With these motivations and, given that there are still few rock physics studies about this particular shale, in this case study we implement a practical calibration procedure to predict densities, sonic velocities and related quantities at well scales. Our formulation combines well known poroelastic rock-physics theories with numerical inversion techniques to estimate fitting and physical parameters, taking into account in the computations the confining stress and pore pressure for each depth. This allows us to calibrate the model under non-hydrostatic differential stress conditions. Another point to highlight is the fact that our procedure does not need to introduce any assumptions about the shape of pores and grains, nor using empirical approximations. The calibrated model permits us to control and replace spurious data and also to derive shear wave velocities, anisotropy parameters, Young’s modulus and Poisson’s ratio logs along the wells under study. The results found allow us to conclude that the proposed workflow is a useful and novel tool that can be applied with real data from any other organic shale reservoir.

Trailing edge cutback film cooling flows are ubiquitous in small and medium gas turbines, but they are difficult to predict accurately due to the inherent deterministic and stochastic unsteadiness that controls the effectiveness of the cooling system. To help develop accurate closure models for such flows, the characteristics of both types of unsteadiness and their effects on the mean flows are analyzed in this research. Zonal detached eddy simulation (ZDES) is performed on a trailing edge cutback flow model, and the numerical results are validated against the measured data. Then, by using spectral proper orthogonal decomposition (SPOD) reconstruction, the original dataset is segregated into deterministic and stochastic unsteadiness. The characteristics of the stress tensor and the heat flux of each type of unsteadiness are analyzed in detail, and notable differences between the two unsteadiness are identified in terms of the stress tensor anisotropy and distribution of unsteady kinetic energy and heat flux. By propagating the unsteadiness through the Reynolds-averaged Navier–Stokes (RANS) equations, the effect of different unsteadiness on the mean flow prediction is quantified. An accurate prediction of the total stress tensor reduces the prediction error in the velocity field by 79% and cooling effectiveness by 55%. An accurate prediction of the total heat flux vector reduces the prediction error in cooling effectiveness further by 37%. These findings provide valuable knowledge for the physical understanding, turbulence modeling, and aerothermal design of cutback trailing edge flows.

Abstract:This article engages with two fundamental attitudes toward animals who are used for human consumption: attention and ironic detachment. Taken as polarities linked with animal consumption and the refusal thereof, I discuss how these two attitudes are shaped and manifested during moments of encounter with the animals in question. Starting from a striking photograph from the Lychee and Dog Meat Festival in China, I explore the embodiment of these attitudes in the "gaze" of human participants during the encounter with animals who are going to be killed for food.

ABSTRACTAs attention, in philosophy, is mainly discussed in the philosophy of mind, its ethical aspects have remained relatively unexplored. One notable exception is Iris Murdoch. Another philosopher, Maurice Merleau-Ponty, considers attention to be central for his phenomenology of perception, with important ethical implications. This paper explores the role of attention in ethics by drawing on both Murdoch and Merleau-Ponty and uses the resources they variously offer to address two questions relating to the enigmatic role of the self in attention: how should we understand agency in the attending subject? And: to what extent is the subject responsible for the quality of her attention? Addressing these difficulties about the self is the key to articulating its ethical value, as well as the main apparent difference between the ethical concept and the one in ordinary language and philosophy of mind.

The economic harm being caused by the novel coronavirus may soon result in multiple sovereign debtors moving into default territory, but the existing playbook for dealing with multi-sovereign emerging market debt crises is blank. Currently, the only way to deal with a debt crisis is to carry out protracted country-by-country and contract-by-contract negotiated workouts. Expert groups are attempting to design a mechanism to run multiple sovereign debt workouts simultaneously but any design will take time to configure and get international buy-in. This article sets forth some options to provide temporary legal protection to debtor countries while they are diverting resources to respond to the Covid-19 pandemic. This is the notion of ‘legal air cover’. The options we propose involve ex-post state intervention in debt contracts and come with risks, but we show that in the case of Greece, where such an intervention was necessary in 2012, there were no negative spillovers on periphery eurozone debt markets associated with the Greek ex-post modification of contract terms.

By conducting both a bottle test and isolate drop–drop experiments, we determine the coalescence rates of water droplets within water-in-oil emulsions stabilized by a large amount of Span 80 in the presence of Tween 20, a surfactant that acts as a demulsifier. Using a microscopic model based on a theory of hole nucleation, we establish an analytical formula that quantitatively predicts the coalescence frequency per unit area of droplets whose interfaces are fully covered by surfactant molecules. Despite its simplicity and the strong assumptions made for its derivation, this formula captures our experimental findings on Span 80-stabilized emulsions as well as other results, found in the literature, remarkably well on a wide range of water-in-crude oil systems.

This article examines the impact of Greece retroactively, via legislation, changing the terms in hundreds of billions of euros worth of Greek government bonds governed by domestic Greek law. As the abrogation of gold clauses in US government bonds by the US Congress in 1933 had been, the Greek action was decried as violative of the rule of law and sure to negatively impact the future ability of Euro area sovereigns to borrow. We test whether the Greek action had negative spillovers on European government debt markets. We find no evidence of increased borrowing for even the most peripheral European economies from the Greek action.