Trees face the dilemma that achieving high plant productivity is accompanied by a risk of drought-induced hydraulic failure due to a trade-off in the trees' vascular system between hydraulic efficiency and safety. By investigating the xylem anatomy of branches and coarse roots, and measuring branch axial hydraulic conductivity and vulnerability to cavitation in 4-year-old field-grown aspen plan...

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...

In this talk we present a joint work with Feng-Bin Wang and Xiaoqiang Zhao. The work concerns with a periodically pulsed bio-reactor model of a flowing water habitat with a hydraulic storage zone in which no flow occurs. The full system can be reduced to a limiting system based on a conservation principle. Then we obtain sufficient conditions in terms of principal eigenvalues for the persistenc...

Hydraulic fracturing is an important method of reservoir stimulation in the exploitation of geothermal resources, and conventional and unconventional oil and gas resources. In this article, hydraulic fracturing experiments with shale, sandstone cores (from southern Sichuan Basin), and granite cores (from Inner Mongolia) were conducted to investigate the different hydraulic fracture extension pa...

Hydraulic activity refers to a property most familiar when discussing hydraulic cement such as ordinary portland cement (OPC). ASTM C125-15a defines hydraulic cement as “a cement that sets and hardens by chemical reaction with water and is capable of doing so under water.” That is, hydraulic cements, including SCMs that have hydraulic properties, react with water to harden, and that hardening p...

A practical approach to design a feedforward-plus-proportional-integral-derivative (FPID) controller for accurate and smooth velocity control on a hydraulic linear actuator is presented. The integrated controller consists of a feedforward loop and a PID loop. The feedforward loop is designed to compensate for the nonlinearity of the electrohydraulic system, including the deadband of the system ...

The Hydraulic excavator machines are heavy duty earth mover consisting of a boom, arm and bucket. It works on principle of hydraulic fluid with hydraulic cylinder and hydraulic motors. The Hydraulic excavator backhoe operation require coordinated movement of boom, arm and bucket to control the bucket tip position by following a desired trajectory and to use the excavator machines effectively in...

abstract many studies have been conducted on the characteristics of hydraulic jump over gradually expanding cross sections, but comparatively few have been carried out on basins with convergent wall. in the present research, the hydraulic jump characteristic of the stilling basin with convergent wall has been investigated. the main objective of this research is evaluation of conjugate depths ra...