2,082 research outputs found
Media coverage of stand your ground laws deters crime in some cities, but not in others
So-called ‘stand your ground laws’ – which give people the right to use deadly force to defend themselves – have now been in place for a decade. In new research which uses a Texas shooting incident as a case study, Ling Ren, Yan Zhang, and Jihong “Solomon” Zhao examine whether or not the publicity over shooting incidents where the law is invoked helps to deter crime – specifically residential and business burglaries. They find that such media coverage of high-profile incidents does have a deterrent effect in some nearby cities, but not in others
Nodal-link semimetals
In topological semimetals, the valence band and conduction band meet at
zero-dimensional nodal points or one-dimensional nodal rings, which are
protected by band topology and symmetries. In this Rapid Communication, we
introduce "nodal-link semimetals", which host linked nodal rings in the
Brillouin zone. We put forward a general recipe based on the Hopf map for
constructing models of nodal-link semimetal. The consequences of nodal ring
linking in the Landau levels and Floquet properties are investigated.Comment: 12 pages, 5 figures, including supplemental material. Published
versio
Analysis of the Dielectric Constant of Saline-Alkali Soils and the Effect on Radar Backscattering Coefficient: A Case Study of Soda Alkaline Saline Soils in Western Jilin Province Using RADARSAT-2 Data
Soil salinity is a global problem, especially in developing countries, which affects the environment and productivity of agriculture areas. Salt has a significant effect on the complex dielectric constant of wet soil. However, there is no suitable model to describe the variation in the backscattering coefficient due to changes in soil salinity content. The purpose of this paper is to use backscattering models to understand behaviors of the backscattering coefficient in saline soils based on the analysis of its dielectric constant. The effects of moisture and salinity on the dielectric constant by combined Dobson mixing model and seawater dielectric constant model are analyzed, and the backscattering coefficient is then simulated using the AIEM. Simultaneously, laboratory measurements were performed on ground samples. The frequency effect of the laboratory results was not the same as the simulated results. The frequency dependence of the ionic conductivity of an electrolyte solution is influenced by the ion’s components. Finally, the simulated backscattering coefficients measured from the dielectric constant with the AIEM were analyzed using the extracted backscattering coefficient from the RADARSAT-2 image. The results show that RADARSAT-2 is potentially able to measure soil salinity; however, the mixed pixel problem needs to be more thoroughly considered
DESCN: Deep Entire Space Cross Networks for Individual Treatment Effect Estimation
Causal Inference has wide applications in various areas such as E-commerce
and precision medicine, and its performance heavily relies on the accurate
estimation of the Individual Treatment Effect (ITE). Conventionally, ITE is
predicted by modeling the treated and control response functions separately in
their individual sample spaces. However, such an approach usually encounters
two issues in practice, i.e. divergent distribution between treated and control
groups due to treatment bias, and significant sample imbalance of their
population sizes. This paper proposes Deep Entire Space Cross Networks (DESCN)
to model treatment effects from an end-to-end perspective. DESCN captures the
integrated information of the treatment propensity, the response, and the
hidden treatment effect through a cross network in a multi-task learning
manner. Our method jointly learns the treatment and response functions in the
entire sample space to avoid treatment bias and employs an intermediate pseudo
treatment effect prediction network to relieve sample imbalance. Extensive
experiments are conducted on a synthetic dataset and a large-scaled production
dataset from the E-commerce voucher distribution business. The results indicate
that DESCN can successfully enhance the accuracy of ITE estimation and improve
the uplift ranking performance. A sample of the production dataset and the
source code are released to facilitate future research in the community, which
is, to the best of our knowledge, the first large-scale public biased treatment
dataset for causal inference.Comment: Accepted by SIGKDD 2022 Applied Data Science Trac
6-Chloro-8-methyl-4H-3,1-benzoxazine-2,4(1H)-dione
The two molecules in the asymmetric unit of the title compound, C9H6ClNO3, are nearly planar, with r.m.s. deviations of 0.034 and 0.037 Å. The crystal structure is stabilized by two weak intermolecular N—H⋯O interactions
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