scholarly journals Development of a Matlab(R) Toolbox for the Design of Grey-Box Neural Models

2006 ◽  
Vol 1 (2) ◽  
pp. 7 ◽  
Author(s):  
Gonzalo Acuña ◽  
Erika Pinto
Keyword(s):  
Neural Network ◽  
Gaussian Noise ◽  
Network Models ◽  
Neural Models ◽  
Neural Network Models ◽  
Matlab Toolbox ◽  
Validation Data ◽  
Stirred Reactor ◽  
One Step ◽  
Design Construction

A Matlab Toolbox is developed for the design, construction and validation of grey-box neural network models. This toolbox, available in www.diinf.usach.cl=gacuna has been tested in simulations with a continuously stirred reactor process. The grey-box model performs well for validation data with 5% additive gaussian noise for one-step-ahead (OSA) and model-predictive-output (MPO) estimations.

scholarly journals Multiple Ensemble Neural Network Models with Fuzzy Response Aggregation for Predicting COVID-19 Time Series: The Case of Mexico

Healthcare ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 181 ◽  
Author(s):  
Patricia Melin ◽  
Julio Cesar Monica ◽  
Daniela Sanchez ◽  
Oscar Castillo
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Time Series ◽  
Fuzzy Logic ◽  
Network Models ◽  
Neural Network Models ◽  
Validation Data ◽  
Data Set ◽  
Ensemble Neural Networks ◽  
Ensemble Neural Network

In this paper, a multiple ensemble neural network model with fuzzy response aggregation for the COVID-19 time series is presented. Ensemble neural networks are composed of a set of modules, which are used to produce several predictions under different conditions. The modules are simple neural networks. Fuzzy logic is then used to aggregate the responses of several predictor modules, in this way, improving the final prediction by combining the outputs of the modules in an intelligent way. Fuzzy logic handles the uncertainty in the process of making a final decision about the prediction. The complete model was tested for the case of predicting the COVID-19 time series in Mexico, at the level of the states and the whole country. The simulation results of the multiple ensemble neural network models with fuzzy response integration show very good predicted values in the validation data set. In fact, the prediction errors of the multiple ensemble neural networks are significantly lower than using traditional monolithic neural networks, in this way showing the advantages of the proposed approach.

scholarly journals Spectra Recognition Model for O-type Stars Based on Data Augmentation

2021 ◽  
Vol 8 ◽  
Author(s):  
Wen-Yu Yang ◽  
Ke-Fei Wu ◽  
A-Li Luo ◽  
Zhi-Qiang Zou
Keyword(s):  
Neural Network ◽  
Data Augmentation ◽  
Network Models ◽  
Neural Network Models ◽  
Generative Adversarial Network ◽  
Validation Data ◽  
Data Set ◽  
Recognition Model ◽  
Adversarial Network ◽  
The Neural Network

It is an ongoing issue in astronomy to recognize and classify O-type spectra comprehensively. The neural network is a popular recognition model based on data. The number of O-stars collected in LAMOST is <1% of AFGK stars, and there are only 127 O-type stars in the data release seven version. Therefore, there are not enough O-type samples available for recognition models. As a result, the existing neural network models are not effective in identifying such rare star spectra. This paper proposed a novel spectra recognition model (called LCGAN model) to solve this problem with data augmentation, which is based on Locally Connected Generative Adversarial Network (LCGAN). The LCGAN introduced the locally connected convolution and two timescale update rule to generate O-type stars' spectra. In addition, the LCGAN model adopted residual and attention mechanisms to recognize O-type spectra. To evaluate the performance of proposed models, we conducted a comparative experiment using a stellar spectral data set, which consists of more than 40,000 spectra, collected by the large sky area multi-object fiber spectroscopic telescope (LAMOST). The experimental results showed that the LCGAN model could generate meaningful O-type spectra. In our validation data set, the recognition accuracy of the data enhanced recognition model can reach 93.67%, 8.66% higher than that of the non-data enhanced identification model, which lays a good foundation for further analysis of astronomical spectra.

scholarly journals Pemodelan Generator Uap Berbasis Jaringan Saraf Tiruan dengan Algoritme Pelatihan BPGD-ALAM

2016 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Fadhlia Annisa ◽  
Agfianto Eko Putra
Keyword(s):  
Neural Network ◽  
Steam Generator ◽  
Multiple Input Multiple Output ◽  
Network Models ◽  
Training Data ◽  
Training Process ◽  
Training Simulator ◽  
Neural Network Models ◽  
Validation Data ◽  
Testing Data

Steam generator is unit plant which has nonlinear and complex system with multiple-input-multiple-output (MIMO) configuration which is hard to be modeled. Whereas, steam generator model is very useful to create simulation such as operator training simulator (OTS). The purpose of this research is to obtain model of steam generator which has 8 output parameters and 9 input parameters based neural network (NN) with BPGD-ALAM training algorithm. Data had been taken from steam generator of PT. Chevron Pacific Indonesia, Duri and it is divided into three types, i.e training data, validation data and testing data. Training data was used to obtain model for each ouput through training process. Verification model is also done for each epoch using validation data to monitor training process whether overfitting occurs or not. Eight NN model of each output which is obtained from training and verification, is tested using testing data for getting its performance. From the reseach results, architecture of neural network models are obtained with various configuration for each output with RMSE value under 9.71 %. It shows that model which has been obtained, close with steam generator real system.

scholarly journals On the Determination of Groundwater Level using Temporal and Spatial Parameters: Advanced Machine Learning Methods

2021 ◽  
Author(s):  
Amirhossein Najafabadipour ◽  
Gholamreza Kamali ◽  
Hossein Nezamabadi-pour
Keyword(s):  
Neural Network ◽  
Network Model ◽  
Neural Network Model ◽  
Groundwater Level ◽  
Network Models ◽  
Machine Intelligence ◽  
Neural Network Models ◽  
Validation Data ◽  
Data Set ◽  
Spatial Parameters

Abstract Prediction of groundwater level is a useful tool for managing groundwater resources in the mining area. Water resources management requires identifying potential periods for groundwater drainage to prevent groundwater from entering the mine pit and reduce high costs. For this purpose, four multilayer perceptron (MLP) neural network models and four cascade forward (CF) neural network models optimized with Bayesian Regularization (BR), Levenberg-Marquardt (LM), Resilient Backpropagation (RB), and Scaled Conjugate Gradient (SCG), as well as a radial basis function (RBF) neural network model and a generalized regression (GR) neural network model were developed to predict groundwater level using 1377 data point. This data set includes 12 spatial parameters divided into two categories of sediments and bedrock, and besides, 6 time series parameters have been used. Also, to determine the best models and combine them, 165 extra validation data points have been used. After identifying the best models from the three candidate models with lower average absolute relative error (AARE) value, the committee machine intelligence system (CMIS) model has been developed. The proposed CMIS model predicts groundwater level data with high accuracy with an AARE value of less than 0.11%. Also, the proposed model was compared with ten other models through graphical and statistical error analysis. The results show that the developed CMIS model performs better than other existing models in terms of precision and validity range. The relevancy factor indicates that the electrical resistivity of sediments had the highest effect on the groundwater level. Eventually, the quality of the data used was investigated both statistically and graphically, and the results show satisfactory reliability of the data used.

scholarly journals System Development for Liquid Chemicals Point Injection Based on Convolutional Neural Network Models

2021 ◽  
Vol 15 (2) ◽  
pp. 41-45
Author(s):  
V. S. Semenyuk ◽  
E. A. Nikitin
Keyword(s):  
Neural Network ◽  
Convolutional Neural Network ◽  
Plant Protection ◽  
System Development ◽  
Vision System ◽  
Network Models ◽  
Poor Quality ◽  
Neural Network Models ◽  
Validation Data ◽  
Point Injection

The authors showed that one of the reasons for the yield loss is poor-quality determination of the infection degree of agricultural crops by pathogens. They proposed a system of liquid chemicals point application. They identified the possibility of calculating the required amount of fertilizers and protective equipment. (Research purpose) To develop a system of liquid chemicals point application for plant protection and nutrition based on a convolutional neural network model. (Materials and methods) The authors analyzed the existing methods of machine learning. When developing the system, they used the U-net-algorithm of convolutional neural networks, as well as data displaying diseases of winter and spring wheat – brown rust and powdery mildew. Each image was cropped by hand and marked up using a specialized Python library. In the course of applying the architecture, the authors experimentally chose the optimal metrics (jaccard metric), the learning rate – 0.0001 seconds, the number of epochs – 300, and other indicators. (Results and discussion) The authors found that when a new, previously unavailable image was submitted to the algorithm, it recognized the disease in a few seconds and returned to the user not only the original image, but also a mask over it. The accuracy of applying the mask to the affected area was determined – 80 percent. They showed that the predicted error on the validation data was 0.18758. In practice, it could differ from the declared one by no more than 10-15 percent. The authors suggested using the algorithm with a vision system. (Conclusions) The authors showed that technical means imperfection for plants chemicalization increased the consumption up to 30 percent relative to the volume required for point application. They developed a neural network algorithm for identifying the affected areas of plants and proposed the concept of a point chemicals application in order to reduce the costs of processing crops. It was determined that the neural network was able to diagnose the affected areas of plants in 1 second.

A Neural Model of Memory Impairment in Diffuse Cerebral Atrophy

1995 ◽  
Vol 166 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Eytan Ruppin ◽  
James A. Reggia
Keyword(s):  
Neural Network ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Memory Impairment ◽  
Clinical Manifestations ◽  
Cerebral Atrophy ◽  
Network Models ◽  
Neural Model ◽  
Neural Models ◽  
Neural Network Models

BackgroundComputer-supported neural network models have been subjected to diffuse, progressive deletion of synapses/neurons, to show that modelling cerebral neuropathological changes can predict the pattern of memory degradation in diffuse degenerative processes such as Alzheimer's disease. However, it has been suggested that neural models cannot account for more detailed aspects of memory impairment, such as the relative sparing of remote versus recent memories.MethodThe latter claim is examined from a computational perspective, using a neural associative memory model.ResultsThe neural network model not only demonstrates progressive memory deterioration as diffuse network damage occurs, but also exhibits differential sparing of remote versus recent memories.ConclusionsOur results show that neural models can account for a large variety of experimental phenomena characterising memory degradation in Alzheimer's patients. Specific testable predictions are generated concerning the relation between the neuroanatomical findings and the clinical manifestations of Alzheimer's disease.

scholarly journals Neural Models of Text Normalization for Speech Applications

2019 ◽  
Vol 45 (2) ◽  
pp. 293-337 ◽  
Author(s):  
Hao Zhang ◽  
Richard Sproat ◽  
Axel H. Ng ◽  
Felix Stahlberg ◽  
Xiaochang Peng ◽  
...  
Keyword(s):  
Neural Network ◽  
Machine Learning ◽  
Language Processing ◽  
Speech Synthesis ◽  
Network Models ◽  
Neural Models ◽  
Neural Network Models ◽  
Sentential Context ◽  
Finite State ◽  
Text Normalization

Machine learning, including neural network techniques, have been applied to virtually every domain in natural language processing. One problem that has been somewhat resistant to effective machine learning solutions is text normalization for speech applications such as text-to-speech synthesis (TTS). In this application, one must decide, for example, that 123 is verbalized as one hundred twenty three in 123 pages but as one twenty three in 123 King Ave. For this task, state-of-the-art industrial systems depend heavily on hand-written language-specific grammars. We propose neural network models that treat text normalization for TTS as a sequence-to-sequence problem, in which the input is a text token in context, and the output is the verbalization of that token. We find that the most effective model, in accuracy and efficiency, is one where the sentential context is computed once and the results of that computation are combined with the computation of each token in sequence to compute the verbalization. This model allows for a great deal of flexibility in terms of representing the context, and also allows us to integrate tagging and segmentation into the process. These models perform very well overall, but occasionally they will predict wildly inappropriate verbalizations, such as reading 3 cm as three kilometers. Although rare, such verbalizations are a major issue for TTS applications. We thus use finite-state covering grammars to guide the neural models, either during training and decoding, or just during decoding, away from such “unrecoverable” errors. Such grammars can largely be learned from data.

scholarly journals Devizaárfolyam előrejelzés neurális háló modell segítségével = Foreign Exchange Rate Forecast Using Neural Network

2021 ◽  
Vol 16 (1) ◽  
pp. 117-137
Author(s):  
Zsolt Lakatos
Keyword(s):  
Neural Network ◽  
Network Models ◽  
Foreign Exchange Rate ◽  
Neural Models ◽  
Short Term ◽  
Neural Network Models ◽  
Technical Indicators ◽  
The Neural Network ◽  
Master's Thesis ◽  
Technical Indicator

Modelljeimben a technikai indikátorok használatát kapcsolom össze a neurális hálós modellek előrejelző képességeivel. A technikai indikátorok használata mellett szól, hogy rövid távon a pénzügyi idősorok autokorreláltak, a neurális modellek pedig nemlineáris kapcsolatok modellezésére alkalmasak. A kapott eredmények révén azt a következtetést vontam le, hogy ugyan a neurális háló modellek optimalizációs képessége nagyon jó és alkalmazásukkal a megfelelő technikai indikátorok is meghatározhatók, de csak lassan képesek rátanulni az adatokra, így még a legkisebb tranzakciós költség alkalmazása mellett is csak a kezdeti befektetésünk elvesztését tudjuk halogatni. My present paper is the shortened version of my master's thesis in finance presented in November 2015, in which I presented the results of the research implemented in the Training Center for Bankers. In my models I combine the use of technical indicators with predictive capabilities of neural network models. The use of a technical indicator suggests that in the short term the financial timeseries are autocorrelated, and neural models are suitable for modeling nonlinear relationships. Based on the results I concluded that although the optimization capabilities of the neural network models are very good and their application can be determined by the appropriate technical indicators, but learning from timeseries data takes too much time, so even with the smallest transaction cost we can only delay the loss of our initial investment.

Method of complex copper-zinc ore typification using neural network models

2020 ◽  
Vol 5 ◽  
pp. 140-147 ◽  
Author(s):  
T.N. Aleksandrova ◽  
◽  
E.K. Ushakov ◽  
A.V. Orlova ◽  
◽  
...  
Keyword(s):  
Neural Network ◽  
Network Models ◽  
Neural Network Models ◽  
Copper Zinc ◽  
Complex Copper

Digital twin of equipment as a basis for the consumer in digital production

2020 ◽  
Keyword(s):  
Neural Network ◽  
Tool Wear ◽  
Chip Formation ◽  
Network Models ◽  
Machining Accuracy ◽  
Neural Network Models ◽  
Digital Twin ◽  
The Neural Network ◽  
Digital Production ◽  
Cyberphysical System

The neural network models series used in the development of an aggregated digital twin of equipment as a cyber-physical system are presented. The twins of machining accuracy, chip formation and tool wear are examined in detail. On their basis, systems for stabilization of the chip formation process during cutting and diagnose of the cutting too wear are developed. Keywords cyberphysical system; neural network model of equipment; big data, digital twin of the chip formation; digital twin of the tool wear; digital twin of nanostructured coating choice

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