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Design of urban drainage pumping stations is susceptible to land area, water pipe networklayout, surrounding terrain conditions and construction requirements.It is often difficult to meetthe requirements of favourable hydraulic conditions in the design specifications of generalpumping stations. This paper analyzes the inflow characteristics of the forebay of urban pumpingstation, summarizes and classifies the existing rectifier technology of the pumping station intofive types such as diversion pier rectifier technology, diversion grid rectifier technology,bottom sill rectifier technology, pressure plate rectifier technology and water distribution holerectifier technology, and introduces the engineering application status of each technology, andthe advantages, disadvantages and applicable scope of each technology in detail, which can providereference for improving the reliability of urban pumping station system.

In order to study the influence mechanism and law of seepage-stress coupling and thefluctuation of reservoir level on slope stability of small and medium homogeneous earth-rock dams,according to the principle of unsaturated seepage and the simplified Bishop method of rigid bodylimit equilibrium theory, this paper carries out the finite element simulation of seepage andstability of upstream and downstream slopes of homogeneous earth-rock dam under the conditions ofseepage-stress coupling, and sudden rise and sudden drop of reservoir level. The results showthat: Based on the effect of seepage stress coupling, when the reservoir level rises sharply,the safety factor of the upstream dam slope firstly increases rapidly, then slowly, and finallyremains stable, while that of downstream dam slope firstly decreases, then slowly increases, andfinally tends to be stable; When the reservoir level drops sharply, the safety factor ofupstream dam slope firstly decreases rapidly, then slowly, and finally remains stable, while thatof the downstream dam slope firstly increases constantly, then slowly decreases, and finally tends to be stable; In the process of sudden rise and sudden drop of water level, the safety factorof upstream and downstream dam slopes is greater than the minimum safety factor stipulated by thecode, and their anti-sliding stability meets the requirements of the code. The research resultsprovide a reference for risk assessment of small and medium earth-rock dams and danger eliminationand reinforcement measures for reservoir dams in the later stage.

By bifurcation and topological methods, we study the existence/nonexistence and multiplicity of one-sign or nodal solutions of the following k-th mean curvature problem in Minkowski spacetime r N − k v ′ 1 − v ′ 2 k ′ = λ N C N k r N − 1 H k (r , v) in (0 , R) , | v ′ | < 1 in (0 , R) , v ′ (0) = v (R) = 0. As a previous step, we investigate the spectral structure of its linearized problem at zero. Moreover, we also obtain a priori bounds and the asymptotic behaviors of solutions with respect to λ. [ABSTRACT FROM AUTHOR]

Body-conformable light-emitting devices have generated considerable interest because of their widespread potential applications in aerospace, medicine and electronics. These devices, which are flexible, stretchable and soft, can integrate seamlessly and inconspicuously with the human body for tasks such as real-time monitoring, display of information, biosensing, optogenetic stimulation and medical therapy. At present, designs can be roughly divided into three different types: wearable light-emitting textiles, attachable light-emitting skins and implantable light-emitting biodevices. Here we evaluate recent advances in all three areas, discussing the materials design, device engineering strategies and diverse applications of these devices. The outstanding challenges and issues that need to be resolved before achieving widespread adoption and improved capabilities are highlighted. The progress made in developing light-emitting technologies that are wearable, attachable or implantable is reviewed and potential applications and challenges are discussed. [ABSTRACT FROM AUTHOR]

Understanding how drought is impacted by both natural and human influences is crucial to the sustainable utilization and protection of water resources. We established a drought severity index (DSI) based on the terrestrial water storage anomaly (TWSA) derived from the GRACE satellite to detect drought characteristics and trends over ten major river basins in China from 2002 to 2017. The influence of natural factors (terrestrial water storage components, precipitation, evapotranspiration, runoff, NDVI, and teleconnection factors (ENSO, PDO, NAO, and AO)) and a human factor (LULC) on drought were investigated and quantified from the perspective of water storage components based on the Theil–Sen trend and Mann–Kendall test method, the perspective of climate change based on cross wavelet transforms, and the perspective of water balance based on Random Forest. The results indicated that (1) almost all humid and arid basins experienced major drought periods during 2002–2006 and 2014–2017, respectively. The southern IRB and central YZRB regions exhibited notable declines in DSI trends, while the majority of the HLRB, IRB, LRB, YRB, HRB, and SWRB experienced significant increases in DSI trends; (2) abnormal groundwater decreases were the main cause of drought triggered by insufficient terrestrial water storage in most basins; (3) ENSO was the strongest teleconnection factor in most humid basins, and NAO, PDO, and AO were the strongest teleconnection factors in the arid basins and PRB. Most significant resonance cycles lasted 12–64 months in 2005–2014; and (4) the influence of an anthropogenic driver (LULC) has become as important as, or more important than, natural factors (runoff and teleconnection factors) on hydrological drought. [ABSTRACT FROM AUTHOR]