The dynamic mechanical properties of dam concrete play a critical role in the seismic design dams. Conducting experiments on large-scale fully graded specimens to accurately obtain is challenging task. Dam performance typically evaluated using standard-sized wet-screened specimens. Therefore, it essential understand relationship between and under loading; however, research this field scarce. This study investigated flexural compression tests strain rates corresponding loading. for were set...

The levels of tropospheric ozone (O3) are closely related to regional meteorological conditions, precursor emissions, and geographical environments, which have a significant negative impact on human health. concentrations O3 were relatively low, while the spatial distribution was strongly heterogeneous in Northeast China; however, little is known about how influencing factors affect China. Here, concentration, observation data, precursors (NO2), vegetation coverage data from 41 monitoring...

Millions of children attending US schools are exposed to traffic-related air pollutants, including health-relevant ultrafine aerosols generated from school buses powered with diesel fuel. This case study was established in a midwestern (USA) metropolitan area determine the concentration and elemental composition aerosol vicinity public during morning hours when bus traffic out adjacent depot especially intense. Simultaneous measurements were performed at control site. The ambient first...

Meteorological droughts are natural disasters that have been linked to economic losses and casualties. Decision-makers need understand the temporal spatial variation of meteorological drought events at a daily weekly scale develop more elaborate framework for risk management. The present study used standardized weighted average precipitation index (SWAP) as an indicator droughts, computed from dataset (1960–2015) 34 stations in Chongqing, China. multi-threshold run theory was applied...

The dynamic fracture behavior of mass concrete is crucial to the analysis and safety evaluation dams subjected strong earthquake shocks in framework mechanics. In presented research, cylindrical specimens with a ring preset cracks were cast by three-graded concrete, direct tension tests performed two loading rates considered, i.e., 10−6/s for quasi-static 10−3/s loading. load–crack mouth opening displacement (P-CMOD) curves obtained, from which toughness, energy, characteristic length...

China is one of the countries that seriously suffered desertification in world, and it very meaningful to develop a quantitative method assess at large scale. In this study, MODIS images were selected as data resources, NDVI, land surface albedo, soil water index (the reflectance band 7) indicators for assessing desertification. Based on building indicator rule sets different grades sub-regions, authors developed assessment by using decision tree model. The results showed that, study can...

As one popular supercritical CO2 (sCO2) power cycle, the recompression cycle has attracted various modifications. However, comparative studies are still required to determine whether these modifications necessary. In this paper, three on original cycle(I) compared, which reheating cycle(II), partial cooling cycle(III), and reheated cycle(IV). Thermodynamic states calculated based recuperator effectiveness, split ratio, pressure pre-cooling by genetic algorithm (GA). The thermal efficiencies...

Abstract In the present research, Schardin’s problem is numerically investigated using a FORTRAN based quasi-DNS solver, numerical results are validated experimental result and shock impinges process analyzed in detail. During process, we noticed that periodical vortex shedding phenomena could be observed, thus, proper orthogonal decomposition (POD) utilized to shed light on flow features during process.

Abstract Based on the large-scale shaking table model test of aqueduct, interaction and influence aqueduct structure-water-damping bearing were studied. Through dynamic detection white noise, free vibration characteristics under different working conditions obtained. comparison seismic responses three water, half water normal level two states locking releasing damping bearing, quality natural frequency, pressure strain structure was By inputting Ricker waves with frequencies, correlation...

In this paper, we present a unified framework to simulate non-Newtonian behaviors. We combine viscous and elasto-plastic stress into particle solver achieve various behaviors ranging from fluid-like solid-like. Our constitutive model is based on Generalized Maxwell model, which incorporates viscosity, elasticity plasticity in one non-linear by way. On the hand, taking advantage of term, construct series strain-rate dependent models for classical such as shear-thickening, shear-thinning,...

In this article, we present a unified framework to simulate non-Newtonian behaviors. We combine viscous and elasto-plastic stress into particle solver achieve various behaviors ranging from fluid-like solid-like. Our constitutive model is based on Generalized Maxwell model, which incorporates viscosity, elasticity plasticity in one non-linear by way. On the hand, taking advantage of term, construct series strain-rate dependent models for classical such as shear-thickening, shear-thinning,...

The design of the strut fuel injector plays an important role in performance strut-based scramjet combustor. current study numerically investigates flow and combustion characteristics a An in-house code was developed to compute Reynolds-averaged Navier-Stokes (RANS) equations coupled with SST k  turbulence model one-step reaction finite-rate/eddy-dissipation model. In order enhance mixing efficiency, we develop novel double-strut concept Firstly, numerical methods are validated by...

Abstract This paper designs an agricultural machinery positioning monitoring system, which can collect the information of operation, and is great significance for precision agriculture. The system uses stm32f103rct6 as controller, with Beidou + GPS dual module display screen other related accessories, to achieve accuracy real-time machinery.

In this paper, the supercritical CO2 (sCO2) recompression cycle combined cycles are analysed, where bottom include transcritical (tCO2), organic Rankine (ORC) or trilateral flash (TFC). The working fluid for ORC and TFC can be R123, R245fa, n-Pentane. We implemented four sub-models in our calculation: 1) thermodynamic model; 2) heat transfer 3) economic 4) exergoeconomic model. specific exergy costing (SPECO) method is utilised model, multi-objective genetic algorithm adopted to give Pareto...

In this paper, the supercritical CO2 (sCO2) recompression cycle combined cycles are analysed, where bottom include transcritical (tCO2), organic Rankine (ORC) or trilateral flash (TFC). The working fluid for ORC and TFC can be R123, R245fa, n-Pentane. We implemented four sub-models in our calculation: 1) thermodynamic model; 2) heat transfer 3) economic 4) exergoeconomic model. specific exergy costing (SPECO) method is utilised model, multi-objective genetic algorithm adopted to give Pareto...

As one popular supercritical CO2 (sCO2) power cycle, the recompression cycle has attracted various modifications. However, comparative studies are still required to determine whether these modifications necessary. In this paper, three on original cycle(I) compared, which reheating cycle(II), partial cooling cycle(III), and reheated cycle(IV). Thermodynamic states calculated based recuperator effectiveness, split ratio, pressure pre-cooling by genetic algorithm (GA). The thermal efficiencies...