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Using real road testing to optimize autonomous driving algorithms is time-consuming and capital-intensive. To solve this problem, we propose a GAN-based model that is capable of generating high-quality images across different domains. We further leverage Contrastive Learning to train the model in a self-supervised way using image data acquired in the real world using real sensors and simulated images from 3D games. In this paper, we also apply an Attention Mechanism module to emphasize features that contain more information about the source domain according to their measurement of significance. Finally, the generated images are used as datasets to train neural networks to perform a variety of downstream tasks to verify that the approach can fill in the gaps between the virtual and real worlds.

Motivated by the recently discovered superconductivity in Sr-doped nickelate oxides NdNiO$_2$, we predict a material BiNiO$_2$ that provides an opportunity to study the intertwined ferroelectricity, metallicity, and magnetism in a crystal with very simple atomic structures. There is a ferroelectric structural transition from the nonpolar phase with the P4/mmm space group to the polar phase with the P4mm space group, which is driven by the lone pair on Bi. Calculations based on the Heyd-Scuseria-Ernzerhof hybrid density functional reveal that both the nonmagnetic and ferromagnetic states are metallic for nonpolar and polar phases, while the lowest energy ground-state for polar BiNiO$_2$ is a Hubbard Mott insulator with the G-type antiferromagnetic spin configurations. As a ferroelectric material with an electric polarization of 0.49 C/m2, it may be possible to control the magnetic order in BiNiO$_2$ by an applied electric field. The replacement of Nd by Bi serves as a connecting link between a high-temperature superconductor and a Mott multiferroic. Our work supports a route towards strongly correlated ferroelectrics., 20 pages, 9 figures, 3 tables

The Rashba and Dresselhaus types of spin-orbit coupling are two typical linear coupling forms. We establish the fundamental physics of a model which can be viewed as the double version of the Rashba and Dresselhaus spin-orbit coupling. This model describes the low energy physics of a class of massless Dirac fermions in spin-orbit systems. The physical properties of the massless Dirac fermions are determined by the mathematical relations of spin-orbit coefficients. For equal Rashba and Dresselhauss coupling constants, k-independent eigenspinors and a persistent spin helix combined with massless birefringent Dirac fermions emerge in this model. The spin-orbit coupled systems described by this model have potential technological applications from spintronics to quantum computation., 12 pages, 4 figures

The Datta-Das-type spin field-effect transistor, using a two-dimensional electron gas in a semiconductor heterostructure as a channel, plays a key role in spintronics. Here, we theoretically present a type of spin field-effect transistor based on massless birefringent Dirac fermions in polar Dirac semimetals. The manipulation of spin arises from the existence of the strong spin-orbit coupling, polar space groups, and Dirac cones in a single phase. The oscillatory channel conductance can be controlled by the sign of gate voltage in addition to its magnitude due to the gapless band structures of polar Dirac semimetals. Such spin field-effect transistor provides guidance for the further design of spintronic devices., Comment: 14 pages, 3 figures

The effects of different microstructure on the dynamical stab-resistant property of TA15 alloy are investigated. The specimens were tested on the stab apparatus after heat treatment at temperature of 850, 930 and 1030°C, time of 30min and air cooled. The impact force-time curves, microstructure and fracture morphology of specimens were analyzed. The results showed that the properties of higher strength and plasticity are benefit to the performance of stab resistance of TA15 specimens, and the curves of 930°C and 850°C exhibit two peaks and longer time ranges, but the curve of 1030°C exhibits the shortest time to reach the peak of impact force, and the specimens heat treated at 850°C exhibit the better performance against the knife impactor because of fine grain and stronger grain boundary binding force to absorb the impact force energy.

2016 International Nanotoxicology Congress in Boston, Massachusetts. This research was supported in part through IHSFC funding to Professor Subhash Risbud, Professor of Material Sciences in the College of Engineering, UC Davis. Center grant support is acknowledged on the poster.

The hot deformation behavior of Ti53311S titanium alloy in the temperature range of 880–1080 °C and strain rate range of 0.001-10 s −1 have been studied by hot compressive testing on a Gleeble-1500 simulator. The flow behavior was described by the hyperbolic sine constitutive equation, the activation energies in (α+ β ) region and in β region were calculated as 641 kJ/mol and 244 kJ/mol, respectively. The microstructure of Ti53311S was observed and analyzed using an optical microscope. The experimental results show that this alloy is sensitive to deformation temperature and strain rate, and the strain rate sensitivity exponent values ( m ) decreases with increasing of deformation temperature while the deformation activation energy ( Q ) increases. The leading deformation mechanism in the single phase β region is dynamic recover, while that in (α+ β ) region is grain boundary slipping and grain globularizing.