A network model for control of inspiratory cutoff by the pneumotaxic center with supportive experimental data in cats

1976 ◽  
Vol 21 (3) ◽  
pp. 131-138 ◽  
Author(s):  
J. L. Feldman
2004 ◽  
Vol 50 (8) ◽  
pp. 103-110 ◽  
Author(s):  
H.K. Oh ◽  
M.J. Yu ◽  
E.M. Gwon ◽  
J.Y. Koo ◽  
S.G. Kim ◽  
...  

This paper describes the prediction of flux behavior in an ultrafiltration (UF) membrane system using a Kalman neuro training (KNT) network model. The experimental data was obtained from operating a pilot plant of hollow fiber UF membrane with groundwater for 7 months. The network was trained using operating conditions such as inlet pressure, filtration duration, and feed water quality parameters including turbidity, temperature and UV254. Pre-processing of raw data allowed the normalized input data to be used in sigmoid activation functions. A neural network architecture was structured by modifying the number of hidden layers, neurons and learning iterations. The structure of KNT-neural network with 3 layers and 5 neurons allowed a good prediction of permeate flux by 0.997 of correlation coefficient during the learning phase. Also the validity of the designed model was evaluated with other experimental data not used during the training phase and nonlinear flux behavior was accurately estimated with 0.999 of correlation coefficient and a lower error of prediction in the testing phase. This good flux prediction can provide preliminary criteria in membrane design and set up the proper cleaning cycle in membrane operation. The KNT-artificial neural network is also expected to predict the variation of transmembrane pressure during filtration cycles and can be applied to automation and control of full scale treatment plants.


Author(s):  
Farrukh Mazhar ◽  
Mohammad A Choudhry ◽  
Muhammad Shehryar

Autonomous flight of an aerial vehicle requires a sufficiently accurate mathematical model, which can capture system dynamics in the presence of external disturbances. Artificial neural network is known for ideal in capturing systems behaviour, where little knowledge about vehicle dynamics is available. In this paper, we explored this potential of artificial neural network for characterizing nonlinear dynamics of an unmanned airship. The flight experimentation data for an outdoor experimental airship are acquired through a series of pre-determined flight tests. The experimental data are subjected to a class of dynamic recurrent neural network model dubbed as nonlinear auto-regressive model with exogenous inputs for training. Sufficiently trained neural network model captured and demonstrated the longitudinal dynamics of the airship satisfactorily. We also demonstrated the usefulness of proposed technique for Lotte airship, wherein the performance of proposed model is validated and analysed for the Lotte airship flight test data.


Author(s):  
Alessandro Orchini ◽  
Georg A. Mensah ◽  
Jonas P. Moeck

In this theoretical and numerical analysis, a low-order network model is used to investigate a thermoacoustic system with discrete rotational symmetry. Its geometry resembles that of the MICCA combustor; the FDF employed in the analysis is that of a single-burner configuration, and is taken from experimental data reported in the literature. We show how most of the dynamical features observed in the MICCA experiment, including the so-called slanted mode, can be predicted within this framework, when the interaction between a longitudinal and an azimuthal thermoacoustic mode is considered. We show how these solutions relate to the symmetries contained in the equations that model the system. We also discuss how considering situations in which two modes are linearly unstable compromises the applicability of stability criteria available in the literature.


2020 ◽  
Vol 161 ◽  
pp. 01031
Author(s):  
Aleksandr Nikiforov ◽  
Aleksei Kuchumov ◽  
Sergei Terentev ◽  
Inessa Karamulina ◽  
Iraida Romanova ◽  
...  

In the work based on agroecological and technological testing of varieties of grain crops of domestic and foreign breeding, winter triticale in particular, conducted on the experimental field of the Smolensk State Agricultural Academy between 2015 and 2019, we present the methodology and results of processing the experimental data used for constructing the neural network model. Neural networks are applicable for solving tasks that are difficult for computers of traditional design and humans alike. Those are processing large volumes of experimental data, automation of image recognition, approximation of functions and prognosis. Neural networks include analyzing subject areas and weight coefficients of neurons, detecting conflict samples and outliers, normalizing data, determining the number of samples required for teaching a neural network and increasing the learning quality when their number is insufficient, as well as selecting the neural network type and decomposition based on the number of input neurons. We consider the technology of initial data processing and selecting the optimal neural network structure that allows to significantly reduce modeling errors in comparison with neural networks created with unprepared source data. Our accumulated experience of working with neural networks has demonstrated encouraging results, which indicates the prospects of this area, especially when describing processes with large amounts of variables. In order to verify the resulting neural network model, we have carried out a computational experiment, which showed the possibility of applying scientific results in practice.


NANO ◽  
2021 ◽  
pp. 2150108
Author(s):  
Baohui Wu ◽  
Yudong LIU ◽  
Dengshi Wang ◽  
Nan Jiang ◽  
Jie Zhang ◽  
...  

Droplet oscillation method is a noncontact experimental approach, which can be used to measure the surface tension of acoustically levitated droplet. In this paper, we obtained huge amounts of experimental data of deionized water and water-based graphene oxide nanofluids within the temperature range of [Formula: see text]8.2–[Formula: see text]C. Based on the experimental data, we analyzed the influence of droplet’s deformation and frequency shift phenomenon on the surface tension of levitated droplet. Eight parameters that strongly correlate with surface tension were found and used as input neurons of artificial neural network model to predict the surface tension of supercooling graphene oxide nanofluids. The experimental data of nonsupercooling graphene oxide nanofluids were used as training set to optimize artificial neural network model, and that of deionized water were served as validation set, which was used to verify the predictive ability of artificial neural network model. The root mean square error of the optimized artificial neural network model to validation set is only 0.2558[Formula: see text]mN/m, and the prediction values of the surface tension of supercooling deionized water were in good agreement with the theoretical values calculated by Vargaftik equation, which indicates that artificial neural network model can deal well with the complex nonlinear relationship. Afterwards, we successfully predicted the surface tension of supercooling nanofluids by means of the optimized artificial neural network model and obviously reduced the dispersion and deviation caused by droplet deformation and other problems during oscillation process.


Author(s):  
Alessandro Orchini ◽  
Georg A. Mensah ◽  
Jonas P. Moeck

In this theoretical and numerical analysis, a low-order network model is used to investigate a thermoacoustic system with discrete rotational symmetry. Its geometry resembles that of the MICCA combustor (Laboratoire EM2C, CentraleSupelec); the flame describing function (FDF) employed in the analysis is that of a single-burner configuration and is taken from experimental data reported in the literature. We show how most of the dynamical features observed in the MICCA experiment, including the so-called slanted mode, can be predicted within this framework, when the interaction between a longitudinal and an azimuthal thermoacoustic mode is considered. We show how these solutions relate to the symmetries contained in the equations that model the system. We also discuss how considering situations in which two modes are linearly unstable compromises the applicability of stability criteria available in the literature.


1996 ◽  
Vol 14 (3) ◽  
pp. 235-248 ◽  
Author(s):  
Y. He ◽  
V. Beck

This paper presents a simple method for calculation of the pressure distribution and the neutral plane position in a high rise building. Non-uniform temperature distributions in the stairshaft of the building and discrete door openings are taken into account. The method has been incor porated into a network model for calculating smoke spread in multi-storey buildings. Computational results are compared with experimental data ob tained by other researchers.


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