Suchergebnisse

Public health events, as the common concern faced by the international community, call for the joint response from all mankind. The outbreak of the COVID-19 has highlighted the problems confronting the global governance of international public health, such as limited functions of international organizations and difficulties in achieving objectives, poor collaboration between governance subjects and their limited performance, overlapping legal basis of governance and blurred core function, and lack of solutions to special problems. The corresponding approaches can be taken to improve the efficiency of the governance of global public health, including supporting the role of international organizations to achieve the objectives, enhancing coordination among international governance subjects to form synergy, promoting the compliance with IHR2005 to avoid conflict of law application and upholding the vision of a community with a shared future for mankind to jointly respond to the special problems.

AbstractWe consider a model of corruption in the form of surround‐bidding in a first‐price procurement auction in which bidders' private cost follows uniform distribution. We find that the briber's high‐price bidding function is less aggressive than honest suppliers' while his low‐price one is more aggressive. As the bribery cost increases, both the briber's low‐price and high‐price bidding functions become less aggressive. The winning probability and expected profit of the briber increase, while the winning probability and expected profit of honest suppliers decrease. Surprisingly, although the briber's high‐price bid may be the winning bid, which is harmful to the procurer, the procurer's expected payment decreases, that is, the procurer benefits from surround‐bidding corruption, because the benefit due to more intense competition outweighs the harm caused by the briber's high‐price bid.

Abstract
Topsoil erosion and mass soil losses from hillslopes have negatively affected water quality, vegetation health, local ecosystems, and livelihood. Studies have stated the effectiveness of vegetation in significantly reducing top-soil erosion and enhancing slope stability. This study aims to better understand the application of erosional models in Haiyuan of Ningxia, a semi-arid region of China. The study site is comprised of 20 experimental plots with 11 vegetation covers and 5 slope gradients in design, which were compared to the benchmark of bare land with each slope gradient. Meteorological data and soil hydraulic measurements were collected from 2005 to 2012, and runoff and sediment load were measured by concrete basins at the base of the slopes, which mainly occurred during the summer storms. Multi-plots provide different combinations of vegetation covers and slopes to identify the driving factors of topsoil erosion during rainfall-runoff events and to examine the threshold behavior of their inter-relationship. In order to determine which models were most applicable to this area, the results of RUSLE and CSLE were applied to the data and compared to the known results.

Aluminum-lithium (Al-Li) alloys are promising to replace traditional high-strength aluminum alloys in aerospace and military industries due to their low density, high specific strength, and excellent corrosion resistance. However, there is little research focused on the laser powder bed fusion (LPBF) of Al-Li alloys due to their poor weldability and high crack susceptibility. In this study, the feasibility of the Al-Li alloy fabricated by LPBF was investigated. The effect of the processing parameters on the densification and crack formation behavior was studied. Finally, after optimizing the processing parameters, crack-free and nearly fully dense 2195 Al-Li alloy 3D-printed samples were obtained. A relative density of 99.92% and a microhardness of 89.1 HV were achieved. ; Mechanical Engineering