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Author(s):  
Jing Wang ◽  
Jinglin Zhou ◽  
Xiaolu Chen

AbstractEnsuring the safety of industrial systems requires not only detecting the faults, but also locating them so that they can be eliminated. The previous chapters have discussed the fault detection and identification methods. Fault traceability is also an important issue in industrial system. This chapter and Chap. 10.1007/978-981-16-8044-1_14 aim at the fault inference and root tracking based on the probabilistic graphical model. This model explores the internal linkages of system variables quantitatively and qualitatively, so it avoids the bottleneck of multivariate statistical model without clear mechanism. The exacted features or principle components of multivariate statistical model are linear or nonlinear combinations of system variables and have not any physical meaning. So the multivariate statistical model is good at fault detection and identification, but not at fault root tracking.


Entropy ◽  
2021 ◽  
Vol 24 (1) ◽  
pp. 25
Author(s):  
Xiafei Tang ◽  
Yuyang Zhou ◽  
Yiqun Zou ◽  
Qichun Zhang

This paper investigates the randomness assignment problem for a class of continuous-time stochastic nonlinear systems, where variance and entropy are employed to describe the investigated systems. In particular, the system model is formulated by a stochastic differential equation. Due to the nonlinearities of the systems, the probability density functions of the system state and system output cannot be characterised as Gaussian even if the system is subjected to Brownian motion. To deal with the non-Gaussian randomness, we present a novel backstepping-based design approach to convert the stochastic nonlinear system to a linear stochastic process, thus the variance and entropy of the system variables can be formulated analytically by the solving Fokker–Planck–Kolmogorov equation. In this way, the design parameter of the backstepping procedure can be then obtained to achieve the variance and entropy assignment. In addition, the stability of the proposed design scheme can be guaranteed and the multi-variate case is also discussed. In order to validate the design approach, the simulation results are provided to show the effectiveness of the proposed algorithm.


2021 ◽  
Vol 31 (16) ◽  
Author(s):  
Arthanari Ramesh ◽  
Iqtadar Hussain ◽  
Hayder Natiq ◽  
Mahtab Mehrabbeik ◽  
Sajad Jafari ◽  
...  

In nonlinear dynamics, the study of chaotic systems has attracted the attention of many researchers around the world due to the exciting and peculiar properties of such systems. In this regard, the present paper introduces a new system with a self-excited strange attractor and its twin strange repeller. The unique characteristic of the presented system is that the system variables are all in their quadratic forms; therefore, the proposed system is called a fully-quadratic system. This paper also elaborates on the study of the bifurcation diagram, the interpretation of Lyapunov exponents, the representation of basin of attraction, and the calculation of connecting curves as the employed method for investigating the system’s dynamics. The investigation of 2D bifurcation diagrams and Lyapunov exponents indicated in this paper can better recognize the system’s dynamics since they are plotted considering simultaneous changes of two parameters. Moreover, the connecting curves of the proposed system are calculated. The system’s connecting curves help identify the system’s different behaviors by providing general information about the nature of the flows.


Author(s):  
Loris Di Cairano

Abstract We recast the Zwanzig's derivation of a non linear generalized Langevin equation (GLE) for a heavy particle interacting with a heat bath in a more general framework showing that it is necessary to readjust the Zwanzig's definitions of the kernel matrix and noise vector in the GLE in order to be able performing consistently the continuum limit. As shown by Zwanzig, the non linear feature of the resulting GLE is due to the non linear dependence of the equilibrium map by the heavy particle variables. Such an equilibrium map represents the global equilibrium configuration of the heat bath particles for a fixed (instantaneous) configuration of the system. Following the same derivation of the GLE, we show that a deeper investigation of the equilibrium map, considered in the Zwanzig's Hamiltonian, is necessary. Moreover, we discuss how to get an equilibrium map given a general interaction potential. Finally, we provide a renormalization procedure which allows to divide the dependence of the equilibrium map by coupling coefficient from the dependence by the system variables yielding a more rigorous mathematical structure of the non linear GLE.


2021 ◽  
Vol 30 (4) ◽  
pp. 393-407
Author(s):  
N Losada-Espinosa ◽  
LX Estévez-Moreno ◽  
M Bautista-Fernández ◽  
H Losada ◽  
GA María ◽  
...  

Given the multi-dimensionality of animal welfare, any monitoring system for slaughter animals should comprise an integrative vision that facilitates animal welfare and food safety assessment. Thus, the aim of this study was to investigate risk factors as possible causes for liver condemnations, hoof disorders, bruise prevalence, and the quality of beef carcases under commercial operating conditions in Mexico. Data were recorded for 143 journeys encompassing 1,040 commercial cattle, originating from feedlots, free-range, and dairy production systems. Details on journey distance, vehicle type, cattle type, and animals' origin were gathered from abattoir reports. We found that carcase bruising (41%) and hoof disorders (43.9%) had the highest prevalence, regardless of the production system. Variables such as cattle type and production system influenced liver condemnations; old bulls extensively raised were more prone to present parasitosis such as Fasciola hepatica. Transportation conditions (journey distance, vehicle type) and cattle type might have influenced the development of hoof disorders in the evaluated animals. Multivariable logistic regression showed that animals' origin was a potential risk factor for severe bruising and high muscle pH, with cull dairy cows getting the most serious damage. In general, cattle transport conditions were factors that showed interactions with three of the evaluated indicators (severe hoof injuries, carcase bruising, meat pH24h). Our study shows the need to implement integrative surveillance to identify risk factors according to the production system from which the animals originate. With this information it is possible to develop strategies to mitigate specific cattle welfare problems.


2021 ◽  
Vol 15 ◽  
pp. 102-109
Author(s):  
Mourad Tiar ◽  
Achour Betka ◽  
Ridha Cheikh ◽  
Said Drid

This paper discusses a comprehensive supervisor control for a hybrid system that comprises the photovoltaic generation , hydrogen system ( Fuel cell ,Electrolyse ) and an ac load is developed in this paper. The objectives of the supervisor control are, primarily, to satisfy the load power demand and, second, allows to store the gas through the electrolyser. For these purposes, the supervisor controller determines the operation mode online of the solar generation subsystem , switching from power regulation to maximum power conversion . Decision criteria for the supervisor based on measurable system variables are presented (voltages, and currents) . Finally, the performance of the supervisor controller is extensively assessed through computer simulation using a comprehensive nonlinear model .


2021 ◽  
Vol 884 (1) ◽  
pp. 012043
Author(s):  
F Latifah ◽  
S A Sutrisnowati

Abstract One of geological disasters which cannot be predicted when it will occur is an earthquake. On May 27, 2006, an earthquake struck Bantul which cause many fatalities. The highest fatalities in Tempel were housewives. This study aims to know: (1) the preparedness levels of housewives in dealing with the dangers of earthquakes, and (2) the improvement efforts of housewives in dealing with the dangers of earthquakes in Tempel, Sidomulyo, Bambanglipuro, Bnatul. The method that used in this research is a qualitative method with a quantitative approach. The geographical approach used in this study is the environmental approach. This is a population study. The population of the study is all of the housewives in Tempel as many as 111 housewives. The data were obtained by using observations, interview, and documentations. The data analysis techniques used were a frequency table and descriptive analysis. The result of the study show that : (1) the preparedness levels of the housewives in dealing with earthquake dangers is on category of “full ready” (43,24%). Knowledge and attitude variables the housewives is on category of full ready (34,23%). Emergency plan variables the hosewives is on category ready (45,94%). Early warning system variables the housewives is on category ready (37,82%). Resource mobilization capabilities variables the housewives is on category ready (43,24%). (2) the improvement efforts to dealing with earthquake dangers are by conducting earthquake trainings and simulations as well as evacuation route installations.


2021 ◽  
Author(s):  
Min Wu ◽  
Jie Ding ◽  
Tingting Yuan ◽  
Min Xiao

Abstract Research on control of multi-variable system with strong coupling has been a significant issue in industry. To accurately eliminate the coupling between system variables and improve the control effect, decoupling control techniques are investigated. In this paper, a decoupling control scheme based on fractional-order proportion integration differentiation neural network and sparrow search algorithm (SSA-FPIDNN) is proposed, where sparrow search algorithm is employed to derive the optimal initial weights, preventing the weights from falling into the local optimum, while the fractional-order algorithm is used to correct its connection weights to improve control accuracy. Compared with traditional PIDNN, the proposed SSA-FPIDNN has better decoupling control performance, and the tracking time can be reduced significantly. Numerical simulation and engineering examples verified its effectiveness.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhao Chen ◽  
Yang Liu ◽  
Hao Sun

AbstractHarnessing data to discover the underlying governing laws or equations that describe the behavior of complex physical systems can significantly advance our modeling, simulation and understanding of such systems in various science and engineering disciplines. This work introduces a novel approach called physics-informed neural network with sparse regression to discover governing partial differential equations from scarce and noisy data for nonlinear spatiotemporal systems. In particular, this discovery approach seamlessly integrates the strengths of deep neural networks for rich representation learning, physics embedding, automatic differentiation and sparse regression to approximate the solution of system variables, compute essential derivatives, as well as identify the key derivative terms and parameters that form the structure and explicit expression of the equations. The efficacy and robustness of this method are demonstrated, both numerically and experimentally, on discovering a variety of partial differential equation systems with different levels of data scarcity and noise accounting for different initial/boundary conditions. The resulting computational framework shows the potential for closed-form model discovery in practical applications where large and accurate datasets are intractable to capture.


Horticulturae ◽  
2021 ◽  
Vol 7 (9) ◽  
pp. 315
Author(s):  
Gastón Gutiérrez-Gamboa ◽  
Nicolás Torres-Huerta ◽  
Miguel Araya-Alman ◽  
Nicolás Verdugo-Vásquez ◽  
Yerko Moreno-Simunovic ◽  
...  

(1) Background: Currently, some ampelographic methods are developing in order to identify grapevine varieties. For this purpose, morpho-colorimetric parameters in leaves have been analyzed by digital imagen analysis, but some environmental conditions may affect their determinations. (2) Methods: A research study was conducted to characterize leaf morpho-colorimetric parameters in five grapevine varieties growing under different plant water status and to discriminate them under these conditions. Leaves were collected in vines, and twelve leaf morpho-colorimetric and fractal dimension variables were assessed. (3) Results: Merlot presented the highest values of perimeter and area to perimeter ratio in leaves and higher leaf area than Chardonnay in both plant water conditions. Most of the leaf morpho-colorimetric variables allowed discriminating the grapevine varieties under the contrasted hydric conditions. Under non-water stress, Carmenère was not related to any measured parameters. Merlot was positively related to most of the leaf morphometric parameters, whereas Chardonnay presented the opposite behavior. RGB color system variables allowed discriminating the grapevine varieties under water stress conditions, and Sauvignon Blanc was not related to any measured parameter. Chardonnay and Pinot Noir were positively related to green color and negatively related to most of the leaf morphometric parameters, whereas Merlot showed the opposite behavior. (4) Conclusions: Leaf morpho-colorimetric and fractal dimension parameters were affected by plant water stress and more variables should be incorporated into the new ampelographic methods in order to characterize leaf morpho-colorimetric parameters of the different grapevine varieties more clearly.


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