Accommodating and cracking mechanisms in low-cycle fatigue

The three main stages of fatigue life (accommodation, crack initiation and crack growth) are briefly reviewed. The cyclic behavior of annealed or predeformed face-centered cubic metals is described. Moreover, two types of alloys (Al-4-Cu and WASPALOY) are examined regarding the influence of the interactions between the precipitates and the dislocations on the cyclic behavior. Data on the percent of life to crack initiation (for a microcrack smaller than about 100 microns) are also given. Finally, experimental and theoretical results on crack growth rates in lowcycle fatigue are described

Low regularity solutions for the general Quasilinear ultrahyperbolic Schr\"odinger equation

We present a novel method for establishing large data local well-posedness in low regularity Sobolev spaces for general quasilinear Schr\"odinger equations with non-degenerate and nontrapping metrics. Our result represents a definitive improvement over the landmark results of Kenig, Ponce, Rolvung and Vega, as it weakens the regularity and decay assumptions to the same scale of spaces considered by Marzuola, Metcalfe, and Tataru, but removes the uniform ellipticity assumption on the metric from their result. Our method has the additional benefit of being relatively simple but also very robust. In particular, it only relies on the use of pseudodifferential calculus for classical symbols.Comment: 52 page

Collisional excitation of water by hydrogen atoms

We present quantum dynamical calculations that describe the rotational excitation of H$_2$O due to collisions with H atoms. We used a recent, high accuracy potential energy surface, and solved the collisional dynamics with the close-coupling formalism, for total energies up to 12 000 cm$^{-1}$. From these calculations, we obtained collisional rate coefficients for the first 45 energy levels of both ortho- and para-H$_2$O and for temperatures in the range T = 5-1500 K. These rate coefficients are subsequently compared to the values previously published for the H$_2$O / He and H$_2$O / H$_2$ collisional systems. It is shown that no simple relation exists between the three systems and that specific calculations are thus mandatory

How much input is nedded from the microstructure to model ductile fracture?

International audienceNew phenomena of ductile behavior are briefly presented that are mostly relevant for anisotropic materials. These include void rotation induced ductility enhancement under off-axes loading and two modes of coalescence that are different from the internal necking mode. The effects associated with some phenomena are of first order and the general question arises as to what microstructural parameters affect ductile behavior

When AIs Outperform Doctors: Confronting the Challenges of a Tort-Induced Over-Reliance on Machine Learning

Someday, perhaps soon, diagnostics generated by machine learning (ML) will have demonstrably better success rates than those generated by human doctors. What will the dominance of ML diagnostics mean for medical malpractice law, for the future of medical service provision, for the demand for certain kinds of doctors, and in the long run for the quality of medical diagnostics itself? This Article argues that once ML diagnosticians, such as those based on neural networks, are shown to be superior, existing medical malpractice law will require superior ML-generated medical diagnostics as the standard of care in clinical settings. Further, unless implemented carefully, a physician\u27s duty to use ML systems in medical diagnostics could, paradoxically, undermine the very safety standard that malpractice law set out to achieve. Although at first doctor + machine may be more effective than either alone because humans and ML systems might make very different kinds of mistakes, in time, as ML systems improve, effective ML could create overwhelming legal and ethical pressure to delegate the diagnostic process to the machine. Ultimately, a similar dynamic might extend to treatment also. If we reach the point where the bulk of clinical outcomes collected in databases are ML-generated diagnoses, this may result in future decisions that are not easily audited or understood by human doctors. Given the well-documented fact that treatment strategies are often not as effective when deployed in clinical practice compared to preliminary evaluation, the lack of transparency introduced by the ML algorithms could lead to a decrease in quality of care. This Article describes salient technical aspects of this scenario particularly as it relates to diagnosis and canvasses various possible technical and legal solutions that would allow us to avoid these unintended consequences of medical malpractice law. Ultimately, we suggest there is a strong case for altering existing medical liability rules to avoid a machine-only diagnostic regime. We argue that the appropriate revision to the standard of care requires maintaining meaningful participation in the loop by physicians the loop

Evaluation of Explanation Methods of AI -- CNNs in Image Classification Tasks with Reference-based and No-reference Metrics

The most popular methods in AI-machine learning paradigm are mainly black boxes. This is why explanation of AI decisions is of emergency. Although dedicated explanation tools have been massively developed, the evaluation of their quality remains an open research question. In this paper, we generalize the methodologies of evaluation of post-hoc explainers of CNNs' decisions in visual classification tasks with reference and no-reference based metrics. We apply them on our previously developed explainers (FEM, MLFEM), and popular Grad-CAM. The reference-based metrics are Pearson correlation coefficient and Similarity computed between the explanation map and its ground truth represented by a Gaze Fixation Density Map obtained with a psycho-visual experiment. As a no-reference metric, we use stability metric, proposed by Alvarez-Melis and Jaakkola. We study its behaviour, consensus with reference-based metrics and show that in case of several kinds of degradation on input images, this metric is in agreement with reference-based ones. Therefore, it can be used for evaluation of the quality of explainers when the ground truth is not available.Comment: Due to a bug found in the code, all tables and figures were redone. The new results did not change the main conclusion, except for the best explainer. FEM has performed better than MLFEM; 25 pages, 16 tables, 16 figures; Submitted to "Advances in Artificial Intelligence and Machine Learning" (ISSN: 2582-9793

U.S. Taxation Of The Value Of Executive Services Performed For Multinational Joint Ventures

Domestic U. S. businesses forming a joint venture with a commonly-controlled foreign affiliates need always to take into account transfer pricing rules, whereby any income, deductions, or credits or one may be reallocated from one of the businesses to the other. This problem provides special concerns with regards to compensation for executive services, where calculation of an arm’s length amount is more difficult, and where other contractual rights may have an impact on the determination of the arm’s length amount. The concept of transfer pricing rules with regard to services was first addressed in 1968 regulations, after which there were temporary regulations in 2003 that were finalized in 2009. However, there are still many issues that have not been addressed, that will need to be resolved in a future set of regulations