4,717 research outputs found

    Does Corporate Social Responsibility Benefit Society?

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    In short, it depends on the ownership type. We construct an event-based outcome measure of firm-level environmental, social, and governance (ESG) impact for public and private firms globally from 2007 to 2015 using data from RepRisk. Then, we measure the societal impact of corporate social responsibility (CSR) engagements using participation in the United Nations Global Compact as a proxy. We demonstrate a striking difference between public and private firms: while private firms significantly reduce their negative ESG incident levels after CSR engagements, public firms fail to do so. We attribute this difference to the conflicts of interest between shareholders and stakeholders, which are more pronounced in public firms than private firms. We empirically validate this interpretation through examination of scenarios with varying levels of conflict intensity. We find that for issues types with higher conflict intensity such as collective bargaining, supply-chain-related issues, and controversial products and services, the performance gap between public and private firms is even more severe. For issue types with lower conflict intensity such as tax evasion, executive compensation, and overuse and wasting of resources, the performance gap is smaller and even public companies may do better post-commitment. Moreover, the performance gap is also wider for upstream firms than for downstream firms in supply chains. We also rule out a host of alternative interpretations related to time trends and endogeneity issues. Our results show that existing CSR engagements may not necessarily lead to better societal outcomes, and that policy interventions aimed at aligning the interests of different parties can potentially improve the overall outcome.http://deepblue.lib.umich.edu/bitstream/2027.42/136092/1/1335_Li.pd

    Fractal Metamaterial Absorber with Three-Order Oblique Cross Dipole Slot Structure and its Application for In-band RCS Reduction of Array Antennas

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    To miniaturize the perfect metamaterial absorber, a fractal three-order oblique cross dipole slot structure is proposed and investigated in this paper. The fractal perfect metamaterial absorber (FPMA) consists of two metallic layers separated by a lossy dielectric substrate. The top layer etched a three-order oblique fractal-shaped cross dipole slot set in a square patch and the bottom one is a solid metal. The parametric study is performed for providing practical design guidelines. A prototype with a thickness of 0.0106λ (λ is the wavelength at 3.18 GHz) of the FPMA was designed, fabricated, measured, and is loaded on a 1×10 guidewave slot array antennas to reduce the in-band radar cross section (RCS) based on their surface current distribution. Experiments are carried out to verify the simulation results, and the experimental results show that the absorption at normal incidence is above 90% from 3.17 to 3.22GHz, the size for the absorber is 0.1λ×0.1λ, the three-order FPMA is miniaturized 60% compared with the zero-order ones, and the array antennas significantly obtain the RCS reduction without the radiation deterioration

    Physical properties of CO-dark molecular gas traced by C+^+

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    Neither HI nor CO emission can reveal a significant quantity of so-called dark gas in the interstellar medium (ISM). It is considered that CO-dark molecular gas (DMG), the molecular gas with no or weak CO emission, dominates dark gas. We identified 36 DMG clouds with C+^+ emission (data from Galactic Observations of Terahertz C+ (GOT C+) project) and HINSA features. Based on uncertainty analysis, optical depth of HI τHI\tau\rm_{HI} of 1 is a reasonable value for most clouds. With the assumption of τHI=1\tau\rm_{HI}=1, these clouds were characterized by excitation temperatures in a range of 20 K to 92 K with a median value of 55 K and volume densities in the range of 6.2×1016.2\times10^1 cm3^{-3} to 1.2×1031.2\times 10^3 cm3^{-3} with a median value of 2.3×1022.3\times 10^2 cm3^{-3}. The fraction of DMG column density in the cloud (fDMGf\rm_{DMG}) decreases with increasing excitation temperature following an empirical relation fDMG=2.1×103T(ex,τHI=1)f\rm_{DMG}=-2.1\times 10^{-3}T_(ex,\tau_{HI}=1)+1.0. The relation between fDMGf\rm_{DMG} and total hydrogen column density NHN_H is given by fDMGf\rm_{DMG}=1.03.7×1020/NH1.0-3.7\times 10^{20}/N_H. The values of fDMGf\rm_{DMG} in the clouds of low extinction group (AV2.7A\rm_V \le 2.7 mag) are consistent with the results of the time-dependent, chemical evolutionary model at the age of ~ 10 Myr. Our empirical relation cannot be explained by the chemical evolutionary model for clouds in the high extinction group (AV>2.7A\rm_V > 2.7 mag). Compared to clouds in the low extinction group (AV2.7A\rm_V \le 2.7 mag), clouds in the high extinction group (AV>2.7A\rm_V > 2.7 mag) have comparable volume densities but excitation temperatures that are 1.5 times lower. Moreover, CO abundances in clouds of the high extinction group (AV>2.7A\rm_V > 2.7 mag) are 6.6×1026.6\times 10^2 times smaller than the canonical value in the Milky Way. #[Full version of abstract is shown in the text.]#Comment: Accepted for publishing in Astronomy & Astrophysics. 13 pages, 8 figure

    Filament L1482 in the California molecular cloud

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    Aims. The process of gravitational fragmentation in the L1482 molecular filament of the California molecular cloud is studied by combining several complementary observations and physical estimates. We investigate the kinematic and dynamical states of this molecular filament and physical properties of several dozens of dense molecular clumps embedded therein. Methods. We present and compare molecular line emission observations of the J=2--1 and J=3--2 transitions of 12CO in this molecular complex, using the KOSMA 3-meter telescope. These observations are complemented with archival data observations and analyses of the 13CO J=1--0 emission obtained at the Purple Mountain Observatory 13.7-meter radio telescope at Delingha Station in QingHai Province of west China, as well as infrared emission maps from the Herschel Space Telescope online archive, obtained with the SPIRE and PACS cameras. Comparison of these complementary datasets allow for a comprehensive multi-wavelength analysis of the L1482 molecular filament. Results. We have identified 23 clumps along the molecular filament L1482 in the California molecular cloud. All these molecular clumps show supersonic non-thermal gas motions. While surprisingly similar in mass and size to the much better known Orion molecular cloud, the formation rate of high-mass stars appears to be suppressed in the California molecular cloud relative to that in the Orion molecular cloud based on the mass-radius threshold derived from the static Bonnor Ebert sphere. Our analysis suggests that these molecular filaments are thermally supercritical and molecular clumps may form by gravitational fragmentation along the filament. Instead of being static, these molecular clumps are most likely in processes of dynamic evolution.Comment: 10 pages, 9 figures, 2 tables, accepted to Astronomy and Astrophysic
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