An electrical hydraulic control system (electro-hydraulic system) is thought to be a key component in excavator operation systems. Control methods with fixed parameters may not yield optimal performances because has various nonlinear uncertainties due the leakage and compressibility of fluid medium. Hence, novel PID controller based on improved differential evolution (IDE) introduced electro-hy...

1 S fl ow simulations have a multitude of applications at various scales, from irrigation scheduling to obtaining global climate change estimates. Modeling of fl ow in variably saturated soils requires water retention and hydraulic conductivity parameters that are impractical to measure for largescale projects. As opposed to saturated fl ow, the nonlinearity of the unsaturated fl ow constitutiv...

Flood inundation modelling generally involves two steps. The first involves the use of a hydrologic model, such as RORB, to estimate the design flood hydrograph for a given design storm event. These models require several inputs, such as design rainfalls (i.e. duration, intensity & temporal pattern), losses, baseflow and routing parameters; each of which has an associated degree of uncertainty ...

The operability limits of a supersonic combustion engine for an air-breathing hypersonic vehicle are characterized using numerical simulations and an uncertainty quantification methodology. The time-dependent compressible flow equations with heat release are solved in a simplified configuration. Verification, calibration and validation are carried out to assess the ability of the model to repro...

Preaspiration is usually associated with stops rather than fricatives, both at phonological and phonetic levels of description. This study reports the occurrence of phonetic (nonnormative) preaspiration of voiceless fricatives in Scottish Standard English (SSE) spoken in the Central Belt of Scotland. We classify it as non-normative because it is variably present in different speakers, but the d...

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In this paper, an active disturbance rejection control is designed to improve the position tracking performance of electro-hydraulic actuation system in presence parametric uncertainties, non-parametric and external disturbances as well. The observers (Dos) are proposed estimate not only matched lumped uncertainties but also mismatched disturbance. Without velocity measurement, unmeasurable ang...

The main type of geological and technical measures in the oil fields Western Siberia today is hydraulic fracturing. widespread use this method intensifying production due to its undeniable advantages over other technologies. However, fracturing not without significant drawbacks - clogging bottomhole zone with proppant products chemical reactions, as well premature watering products. All above r...

This paper focuses primarily on adaptive dynamic programming (ADP)-based tracking control of the hydraulic-driven flexible robotic manipulator system (HDFRMS) with varying payloads and uncertainties via singular perturbation theory (SPT). Firstly, dynamics is derived using a driven Jacobin matrix, which represents coupling between hydraulic servo-driven rigid–flexible established assumed mode m...

Effects of inlet design and vegetation type on tracer dynamics and hydraulic performance were investigated using lithium chloride in eighteen experimental free water surface wetlands. The wetlands received similar water flow but had different vegetation types: 6 emergent vegetation wetlands (EVWs), 6 submerged vegetation wetlands (SVWs) and 6 free development wetlands (FDWs). Two types of inlet...