scholarly journals Application of numerical modeling to reservoir immersion assessment and control in dual-formation hydrogeological unit

Author(s):  
Yun Yang ◽  
Wengui Nan ◽  
Shenggen Guo ◽  
Dan Jin ◽  
Jianhui Wu ◽  
...  

Abstract Reservoir immersion is a serious environmental geological issue in a dual-formation structural reservoir bank (DFB) induced by dynamic surface water impoundment (SWI) that has implications for low-lying farmland and buried infrastructure. It is a major challenge to identify the dynamic immersion process and make economic and scientific joint mitigation measures for controlling groundwater immersion. Here, we develop a three-dimensional groundwater flow model and apply it to evaluate and control reservoir immersion in the typical low-lying DFB of Xingan Navigation and Power Junction Project (XGNPJ) across Ganjiang River in Jiangxi Province, China. The field-scale model is well calibrated to predict where the groundwater immersion could potentially occur. Furthermore, the effectiveness of the countermeasures adopted for the reduction of reservoir immersion areas were analysed based on the simulation model by considering the projected future combination scenarios of engineering measures. Results indicate that without engineering mitigation measures, SWI generates groundwater inundation across 23% of the total study area. Comprehensive comparative analysis on different seepage control schemes reveals that the joint engineering measures can effectively control the immersion range to 5% of the total area. The findings can provide scientific basis for groundwater immersion assessment and guide immersion control of XGNPJ project.

Author(s):  
Chao Lai ◽  
Weihong Wang ◽  
Zhenghua Liu ◽  
Zheng Ma

A neuro-adaptive fast terminal sliding-mode dynamic surface control method based on a finite-time stable nonlinear extended state observer is applied to integrated guidance and control design for skid-to-turn missile attacking a ground maneuvering target with terminal angle constraints. A three-dimensional integrated guidance and control design model against a maneuvering target for skid-to-turn missile is established without the assumption that the missile velocity vector and the line of sight coincide with each other. The non-singular fast terminal sliding surface is applied to construct the first error surface of dynamic surface control and the first virtual control law is designed to guarantee hitting accuracy with desired terminal angles. The finite-time stable nonlinear extended state observer is designed separately to estimate uncertainties in the system. And the neuro-adaptive technique is applied to compensate estimation errors of nonlinear extended state observer by training a three-layer feedforward neural network online. Synthesizing all of above, a neuro-adaptive fast terminal sliding-mode dynamic surface control based on nonlinear extended state observer is derived on Lyapunov stability theory, which guarantees stability of the system. Finally, the numerical simulations are conducted to demonstrate the effectiveness of the proposed three-dimensional integrated guidance and control scheme.


Symmetry ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 879 ◽  
Author(s):  
Adel Ouannas ◽  
Othman Abdullah Almatroud ◽  
Amina Aicha Khennaoui ◽  
Mohammad Mossa Alsawalha ◽  
Dumitru Baleanu ◽  
...  

Recently, hidden attractors with stable equilibria have received considerable attention in chaos theory and nonlinear dynamical systems. Based on discrete fractional calculus, this paper proposes a simple two-dimensional and three-dimensional fractional maps. Both fractional maps are chaotic and have a unique equilibrium point. Results show that the dynamics of the proposed fractional maps are sensitive to both initial conditions and fractional order. There are coexisting attractors which have been displayed in terms of bifurcation diagrams, phase portraits and a 0-1 test. Furthermore, control schemes are introduced to stabilize the chaotic trajectories of the two novel systems.


2019 ◽  
Vol 42 (6) ◽  
pp. 1097-1109
Author(s):  
Jing Guo ◽  
Jun Zhou ◽  
Bin Zhao

This paper investigates a novel three-dimensional (3D) integrated guidance and control (IGC) method for skid-to-turn (STT) missiles with strap-down seeker. Firstly, a nonlinear IGC model considering seeker’s field-of-view (FOV) constraint is built by employing the strap-down decoupling model, based on which the strict feedback state equation with matched and unmatched uncertainties is derived. Secondly, to handle the FOV angle and the roll angle constraints, an IGC law is proposed by combining dynamic surface control (DSC) approach with integral barrier Lyapunov function (iBLF), by which an adaptive law is employed to estimate the square of the disturbance bound. Finally, the uniform ultimately boundedness of the closed-loop system is proved strictly based on the Lyapunov stability theory, and the effectiveness and robustness of the proposed IGC scheme are illustrated with numerical simulations.


2020 ◽  
Vol 64 (2) ◽  
pp. 20506-1-20506-7
Author(s):  
Min Zhu ◽  
Rongfu Zhang ◽  
Pei Ma ◽  
Xuedian Zhang ◽  
Qi Guo

Abstract Three-dimensional (3D) reconstruction is extensively used in microscopic applications. Reducing excessive error points and achieving accurate matching of weak texture regions have been the classical challenges for 3D microscopic vision. A Multi-ST algorithm was proposed to improve matching accuracy. The process is performed in two main stages: scaled microscopic images and regularized cost aggregation. First, microscopic image pairs with different scales were extracted according to the Gaussian pyramid criterion. Second, a novel cost aggregation approach based on the regularized multi-scale model was implemented into all scales to obtain the final cost. To evaluate the performances of the proposed Multi-ST algorithm and compare different algorithms, seven groups of images from the Middlebury dataset and four groups of experimental images obtained by a binocular microscopic system were analyzed. Disparity maps and reconstruction maps generated by the proposed approach contained more information and fewer outliers or artifacts. Furthermore, 3D reconstruction of the plug gauges using the Multi-ST algorithm showed that the error was less than 0.025 mm.


2007 ◽  
Vol 42 (4) ◽  
pp. 303-310 ◽  
Author(s):  
Zhi Chen ◽  
Lin Zhao ◽  
Kenneth Lee ◽  
Charles Hannath

Abstract There has been a growing interest in assessing the risks to the marine environment from produced water discharges. This study describes the development of a numerical approach, POM-RW, based on an integration of the Princeton Ocean Model (POM) and a Random Walk (RW) simulation of pollutant transport. Specifically, the POM is employed to simulate local ocean currents. It provides three-dimensional hydrodynamic input to a Random Walk model focused on the dispersion of toxic components within the produced water stream on a regional spatial scale. Model development and field validation of the predicted current field and pollutant concentrations were conducted in conjunction with a water quality and ecological monitoring program for an offshore facility located on the Grand Banks of Canada. Results indicate that the POM-RW approach is useful to address environmental risks associated with the produced water discharges.


Author(s):  
Joseph Ayers

This chapter describes how synthetic biology and organic electronics can integrate neurobiology and robotics to form a basis for biohybrid robots and synthetic neuroethology. Biomimetic robots capture the performance advantages of animal models by mimicking the behavioral control schemes evolved in nature, based on modularized devices that capture the biomechanics and control principles of the nervous system. However, current robots are blind to chemical senses, difficult to miniaturize, and require chemical batteries. These obstacles can be overcome by integration of living engineered cells. Synthetic biology seeks to build devices and systems from fungible gene parts (gene systems coding different proteins) integrated into a chassis (induced pluripotent eukaryotic cells, yeast, or bacteria) to produce devices with properties not found in nature. Biohybrid robots are examples of such systems (interacting sets of devices). A nascent literature describes genes that can mediate organ levels of organization. Such capabilities, applied to biohybrid systems, portend truly biological robots guided, controlled, and actuated solely by life processes.


Author(s):  
Adra Benhacine ◽  
Zoubir Nemouchi ◽  
Lyes Khezzar ◽  
Nabil Kharoua

A numerical study of a turbulent plane jet impinging on a convex surface and on a flat surface is presented, using the large eddy simulation approach and the Smagorinski-Lilly sub-grid-scale model. The effects of the wall curvature on the unsteady filtered, and the steady mean, parameters characterizing the dynamics of the wall jet are addressed in particular. In the free jet upstream of the impingement region, significant and fairly ordered velocity fluctuations, that are not turbulent in nature, are observed inside the potential core. Kelvin-Helmholtz instabilities in the shear layer between the jet and the surrounding air are detected in the form of wavy sheets of vorticity. Rolled up vortices are detached from these sheets in a more or less periodic manner, evolving into distorted three dimensional structures. Along the wall jet the Coanda effect causes a marked suction along the convex surface compared with the flat one. As a result, relatively important tangential velocities and a stretching of sporadic streamwise vortices are observed, leading to friction coefficient values on the curved wall higher than those on the flat wall.


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