A WRF-UCM-SOLWEIG framework of 10m resolution to quantify the intra-day impact of urban features on thermal comfort

City-scale outdoor thermal comfort diagnostics are essential for understanding actual heat stress. However, previous research primarily focused on the street scale. Here, we present the WRF-UCM-SOLWEIG framework to achieve fine-grained thermal comfort mapping at the city scale. The background climate condition affecting thermal comfort is simulated by the Weather Research and Forecasting (WRF) model coupled with the urban canopy model (UCM) at a local-scale (500m). The most dominant factor, mean radiant temperature, is simulated using the Solar and Longwave Environmental Irradiance Geometry (SOLWEIG) model at the micro-scale (10m). The Universal Thermal Climate Index (UTCI) is calculated based on the mean radiant temperature and local climate parameters. The influence of different ground surface materials, buildings, and tree canopies is simulated in the SOLWEIG model using integrated urban morphological data. We applied this proposed framework to the city of Guangzhou, China, and investigated the intra-day variation in the impact of urban morphology during a heat wave period. Through statistical analysis, we found that the elevation in UTCI is primarily attributed to the increase in the fraction of impervious surface (ISF) during daytime, with a maximum correlation coefficient of 0.80. Tree canopy cover has a persistent cooling effect during the day. Implementing 40% of tree cover can reduce the daytime UTCI by 1.5 to 2.0 K. At nighttime, all urban features have a negligible contribution to outdoor thermal comfort. Overall, the established framework provides essential input data and references for studies and urban planners in the practice of urban (micro)climate diagnostics and planning

Dynamics and Impacts of Human-Algorithm Consensus in Logistics Scheduling: Evidence from A Field Experiment

Algorithms are being implemented to aid human decision-making and most studies on human-algorithm interactions focus on how to improve human-algorithm cooperation. However, excessive reliance on algorithms in decision-making may hinder the complementary value of humans and algorithms. There is a lack of empirical evidence on the impacts of human-algorithm consensus in collaborative decision-making. To address this gap, this paper reports a large-scale field experiment conducted by one of China\u27s largest logistics firms in the context of route scheduling. The experiment involved assigning routes to either a treatment group, where algorithms and human operators collaborated in decision-making, or a control group, where human operators made decisions independently. We plan to collect data to evaluate the effects of algorithm implementation and to analyze the patterns and effects of human-algorithm consensus in a long-term cooperation. Our study aims to contribute to the literature on human-algorithm interactions in operational decisions

Gaussian Differential Privacy on Riemannian Manifolds

We develop an advanced approach for extending Gaussian Differential Privacy (GDP) to general Riemannian manifolds. The concept of GDP stands out as a prominent privacy definition that strongly warrants extension to manifold settings, due to its central limit properties. By harnessing the power of the renowned Bishop-Gromov theorem in geometric analysis, we propose a Riemannian Gaussian distribution that integrates the Riemannian distance, allowing us to achieve GDP in Riemannian manifolds with bounded Ricci curvature. To the best of our knowledge, this work marks the first instance of extending the GDP framework to accommodate general Riemannian manifolds, encompassing curved spaces, and circumventing the reliance on tangent space summaries. We provide a simple algorithm to evaluate the privacy budget $\mu$ on any one-dimensional manifold and introduce a versatile Markov Chain Monte Carlo (MCMC)-based algorithm to calculate $\mu$ on any Riemannian manifold with constant curvature. Through simulations on one of the most prevalent manifolds in statistics, the unit sphere $S^d$, we demonstrate the superior utility of our Riemannian Gaussian mechanism in comparison to the previously proposed Riemannian Laplace mechanism for implementing GDP

Recipe for single-pair-Weyl-points phonons carrying the same chiral charges

Recently, Wang et al. [Phys. Rev. B, 106, 195129 (2022)] challenged a widely held belief in the field of Weyl physics, demonstrating that single-pair-Weyl-points (SP-WPs) can exist in nonmagnetic spinless systems, contrary to previous assumptions that they could only exist in magnetic systems. Wang et al. observed that the SP-WPs with opposite and even chiral charges (i.e., |C| = 2 or 4) could also exist in nonmagnetic spinless systems. In this Letter, we present a novel finding in which SP-WPs have a partner, namely a charged nodal surface, in nonmagnetic spinless systems. In contrast to previous observations, we show that the SP-WPs can have uneven chiral charges (i.e., |C| = 1). We identify 6 (out of 230) space groups (SGs) that contain such SP-WPs by searching the encyclopedia of emergent particles in three-dimensional crystals. Our finds were confirmed through the phonon spectra of two specific materials Zr3O (with SG 182) and NaPH2NO3 (with SG 173). This discovery broadens the range of materials that can host SP-WPs and applies to other nonmagnetic spinless crystals

Cr3_3X4_4 (X=Se, Te) monolayers as new platform to realize robust spin filter, spin diode and spin valve

Two-dimensional ferromagnetic (FM) half-metals are promising candidates for advanced spintronic devices with small-size and high-capacity. Motivated by recent report on controlling synthesis of FM Cr$_3$Te$_4$ nanosheet, herein, to explore the potential application in spintronics, we designed spintronic devices based on Cr$_3$X$_4$ (X=Se, Te) monolayers and investigated their spin transport properties. We found that Cr$_3$Te$_4$ monolayer based device shows spin filtering and dual spin diode effect when applying bias voltage, while Cr$_3$S$_4$ monolayer is an excellent platform to realize a spin valve. The different transport properties are primarily ascribed to the semiconducting spin channel, which is close to and away from the Fermi level in Cr$_3$Te$_4$ and Cr$_3$Se$_4$ monolayers, respectively. Interestingly, the current in monolayer Cr$_3$Se$_4$ based device also displays a negative differential resistance effect (NDRE) and a high magnetoresistance ratio (up to 2*10$^3$). Moreover, we found thermally induced spin filtering effect and NDRE in Cr$_3$Se$_4$ junction when applying temperature gradient instead of bias voltage. These theoretical findings highlight the potential of Cr$_3$X$_4$ (X=Se, Te) monolayers in spintronic applications and put forward realistic materials to realize nanosale spintronic device

Genuine Dirac half-metal: A 2D d0-type ferromagnet Mg4N4

When the spin-orbit coupling (SOC) is absent, almost all the proposed half-metals with the twofold degenerate nodal points at the K (or K') in two-dimensional (2D) materials are misclassified as "Dirac half-metals" owing to the way graphene was utilized in the earliest studies. Actually, each band crossing point at K or K' is described by a 2D Weyl Hamiltonian with definite chirality; hence, it must be a Weyl point. To the best of our knowledge, there have been no reports of a genuine (i.e., fourfold degenerate) Dirac point half-metal in 2D yet. In this Letter, we proposed for the first time that the 2D d0-type ferromagnet Mg4N4 is a genuine Dirac half-metal with a fourfold degenerate Dirac point at the S high-symmetry point, intrinsic magnetism, high Curie temperature, 100% spin-polarization, robustness to the SOC and uniaxial and biaxial strains, and 100% spin-polarized edge states. The work can be seen as a starting point for future predictions of intrinsically magnetic materials with genuine Dirac points, which will aid the frontier of topo-spintronics researchers

Effect of Li-deficiency impurities on the electron-overdoped LiFeAs superconductor

We use transport, inelastic neutron scattering, and angle resolved photoemission experiments to demonstrate that the stoichiometric LiFeAs is an intrinsically electron-overdoped superconductor similar to those of the electron-overdoped NaFe1-xTxAs and BaFe2-xTxAs2 (T = Co,Ni). Furthermore, we show that although transport properties of the stoichiometric superconducting LiFeAs and Li-deficient nonsuperconducting Li1-xFeAs are different, their electronic and magnetic properties are rather similar. Therefore, the nonsuperconducting Li1-xFeAs is also in the electron overdoped regime, where small Li deficiencies near the FeAs octahedra can dramatically suppress superconductivity through the impurity scattering effect.Comment: 5 figures,5 page

Tomographic Reconstruction of Rolling Contact Fatigues in Rails using 3D Eddy Current Pulsed Thermography

The detection and quantification of the rolling contact fatigue (RCF) in rail tracks are essential for rail safety and condition-based maintenance. The tomographic reconstruction of the rolling contact fatigue is challenging work. The x-ray is unable to do in-situ inspection effectively. This paper proposes a new approach for RCF construction using 3D eddy current pulsed thermography. A differential time-square-root (sqrt) of temperature drop (DTSTD) is proposed as a mean to construct the sectional images and to reconstruct the thermal tomography image. The proposed method is validated through artificial angular crack slots as well as natural RCF crack. The thermal tomographic reconstruction is compared with the x-ray computed tomography on a rail track head cut-off with RCF cracks

The sharp turn: Backward rupture branching during the 2023 Mw 7.8 Kahramanmaraş (Türkiye) earthquake

Multiple lines of evidence indicate that the 2023 Mw 7.8 Kahramanmaraş (Türkiye) earthquake started on a splay fault, then branched bilaterally onto the nearby East Anatolian Fault (EAF). This rupture pattern includes one feature previously deemed implausible, called backward rupture branching: rupture propagating from the splay fault onto the SW EAF segment through a sharp corner (with an acute angle between the two faults). To understand this feature, we perform 2.5-D dynamic rupture simulations considering a large set of possible scenarios. We find that both subshear and supershear ruptures on the splay fault can trigger bilateral ruptures on the EAF, which themselves can be either subshear, supershear, or a mixture of the two. In most cases, rupture on the SW segment of the EAF starts after rupture onset on its NE segment: the SW rupture is triggered by the NE rupture. Only when the EAF has initial stresses very close to failure can its SW segment be directly triggered by the initial splay-fault rupture, earlier than the activation of the NE segment. These results advance our understanding of the mechanisms of multi-segment rupture and the complexity of rupture processes, paving the way for a more accurate assessment of earthquake hazards