Sharpening the boundaries between flux landscape and swampland by tadpole charge

We investigate the vacuum structure of four-dimensional effective theory arising from Type IIB flux compactifications on a mirror of the rigid Calabi-Yau threefold, corresponding to a T-dual of the DeWolfe-Giryavets-Kachru-Taylor model in Type IIA flux compactifications. By analyzing the vacuum structure of this interesting corner of string landscape, it turns out that there exist perturbatively unstable de Sitter (dS) vacua in addition to supersymmetric and non-supersymmetric anti-de Sitter vacua. On the other hand, the stable dS vacua appearing in the low-energy effective action violate the tadpole cancellation condition, indicating a strong correlation between the existence of dS vacua and the flux-induced D3-brane charge (tadpole charge). We also find analytically that the tadpole charge constrained by the tadpole cancellation condition emerges in the scalar potential in a nontrivial way. Thus, the tadpole charge would restrict the existence of stable dS vacua, and this fact underlies the statement of the dS conjecture. Furthermore, our analytical and numerical results exhibit that distributions of $$ \mathcal{O}(1) $$ O 1 parameters in expressions of several swampland conjectures peak at specific values.

Rolling Texture of Cu–30%Zn Alloy Using Taylor Model Based on Twinning and Coplanar Slip

A modified Taylor model, hereafter referred to as the MTCS(Mechanical-Twinning-withCoplanar-Slip)-model, is proposed in the present work to predict weak texture components in the shear bands of brass-type fcc metals with a twin–matrix lamellar (TML) structure. The MTCS-model considers two boundary conditions (i.e., twinning does not occur in previously twinned areas and coplanar slip occurs in the TML region) to simulate the rolling texture of Cu–30%Zn. In the first approximation, texture simulation using the MTCS-model revealed brass-type textures, including Y {1 1 1}⟨1 1 2⟩ and Z {1 1 1}⟨1 1 0⟩ components, which correspond to the observed experimental textures. Single orientations of C (1 1 2)[1 ¯ 1 ¯ 1] and S’ (1 2 3)[4¯ 1¯ 2] were applied to the MTCS-model to understand the evolution of Y and Z components. For the Y orientation, the C orientation rotates toward T (5 5 2)[1 1 5] by twinning after 30% reduction and then toward Y (1 1 1)[1 1 2] by coplanar slip after over 30% reduction. For the Z orientation, the S’ orientation rotates toward T’ (3 2 1)[2 1 ¯4¯] by twinning after 30% reduction and then toward Z (1 1 1)[1 0 1¯] by coplanar slip after over 30% reduction.

Correlation between Taylor Model Prediction and Transmission Electron Microscopy-Based Microstructural Investigations of Quasi-In Situ Tensile Deformation of Additively Manufactured FeCo Alloy

Within this research, the multiscale microstructural evolution before and after the tensile test of a FeCo alloy is addressed. X-ray µ-computer tomography (CT), electron backscattered diffraction (EBSD), and transmission electron microscopy (TEM) are employed to determine the microstructure on different length scales. Microstructural evolution is studied by performing EBSD of the same area before and after the tensile test. As a result, $$\langle$$ ⟨ 001$$\rangle$$ ⟩ ||TD, $$\langle$$ ⟨ 011$$\rangle$$ ⟩ ||TD are hard orientations and $$\langle$$ ⟨ 111$$\rangle$$ ⟩ ||TD is soft orientations for deformation accommodation. It is not possible to predict the deformation of a single grain with the Taylor model. However, the Taylor model accurately predicts the orientation of all grains after deformation. {123}$$\langle$$ ⟨ 111$$\rangle$$ ⟩ is the most active slip system, and {112}$$\langle$$ ⟨ 111$$\rangle$$ ⟩ is the least active slip system. Both EBSD micrographs show grain subdivision after tensile testing. TEM images show the formation of dislocation cells. Correlative HRTEM images show unresolved lattice fringes at dislocation cell boundaries, whereas resolved lattice fringes are observed at dislocation cell interior. Since Schmid’s law is unable to predict the deformation behavior of grains, the boundary slip transmission accurately predicts the grain deformation behavior.

Verisig 2.0: Verification of Neural Network Controllers Using Taylor Model Preconditioning

This paper presents Verisig 2.0, a verification tool for closed-loop systems with neural network (NN) controllers. We focus on NNs with tanh/sigmoid activations and develop a Taylor-model-based reachability algorithm through Taylor model preconditioning and shrink wrapping. Furthermore, we provide a parallelized implementation that allows Verisig 2.0 to efficiently handle larger NNs than existing tools can. We provide an extensive evaluation over 10 benchmarks and compare Verisig 2.0 against three state-of-the-art verification tools. We show that Verisig 2.0 is both more accurate and faster, achieving speed-ups of up to 21x and 268x against different tools, respectively.

Impact of smoking on the income level of Chinese urban residents: a two-wave follow-up of the China Family Panel Study

ObjectivesThis study attempts to analyse the impact of smoking on the income level of Chinese urban residents to provide a reference for creating informed regulations on cigarette smoking.DesignA population-based cohort study.MethodTwo waves of panel data in 2014 and 2016 from the China Family Panel Study were used. A total of 8025 urban adults were identified. The Hausman–Taylor model was used to analyse the theoretical relationship between smoking and income.ResultsThe percentage of current smokers decreased from 27.39% (2014) to 26.24% (2016), while the percentage of former smokers rose from 9.78% to 11.78%. The results from the Hausman–Taylor model showed that current smokers and former smokers are associated with statistically significant decrease in the income of urban residents of 37.70% and 44.00%, respectively, compared with that of non-smokers. After eliminating the impact of smoking on income, the poverty rate among urban residents decreased from 15.33% to 13.63%.ConclusionsSmoking can significantly reduce the income of Chinese urban residents, resulting in immense negative impacts on Chinese society. Therefore, the government should raise the tax rate on tobacco, include smoking cessation treatment in medical insurance coverage, promote publicity campaigns on the awareness of tobacco hazards and encourage smokers to quit smoking early.