624 research outputs found
Application of Soft Computing Techniques to Multiphase Flow Measurement: A Review
After extensive research and development over the past three decades, a range of techniques have been proposed and developed for online continuous measurement of multiphase flow. In recent years, with the rapid development of computer hardware and machine learning, soft computing techniques have been applied in many engineering disciplines, including indirect measurement of multiphase flow. This paper presents a comprehensive review of the soft computing techniques for multiphase flow metering with a particular focus on the measurement of individual phase flowrates and phase fractions. The paper describes the sensors used and the working principle, modelling and example applications of various soft computing techniques in addition to their merits and limitations. Trends and future developments of soft computing techniques in the field of multiphase flow measurement are also discussed
Sensor Signal and Information Processing II
In the current age of information explosion, newly invented technological sensors and software are now tightly integrated with our everyday lives. Many sensor processing algorithms have incorporated some forms of computational intelligence as part of their core framework in problem solving. These algorithms have the capacity to generalize and discover knowledge for themselves and learn new information whenever unseen data are captured. The primary aim of sensor processing is to develop techniques to interpret, understand, and act on information contained in the data. The interest of this book is in developing intelligent signal processing in order to pave the way for smart sensors. This involves mathematical advancement of nonlinear signal processing theory and its applications that extend far beyond traditional techniques. It bridges the boundary between theory and application, developing novel theoretically inspired methodologies targeting both longstanding and emergent signal processing applications. The topic ranges from phishing detection to integration of terrestrial laser scanning, and from fault diagnosis to bio-inspiring filtering. The book will appeal to established practitioners, along with researchers and students in the emerging field of smart sensors processing
Intelligent Multiphase Flow Measurement
The oil and gas industry’s goal of developing high performing multiphase flow metering
systems capable of reducing costs in the exploitation of marginal oil and gas reserves, especially
in remote environments, cannot be over emphasised.
Development of a cost-effective multiphase flow meter to determine the individual phase flow
rates of oil, water and gas was experimentally investigated by means of low cost, simple and
non-intrusive commercially available sensors. Features from absolute pressure, differential
pressure (axial), gamma densitometer, conductivity and capacitance meters, in combination
with pattern recognition techniques were used to detect shifts in flow conditions, such as flow
structure, pressure and salinity changes and measured multiphase flow parameters
simultaneously without the need for preconditioning or prior knowledge of either phase.
The experiments were carried out at the National Engineering Laboratory (NEL) Multiphase
facility. Data was sampled at 250 Hz across a wide spectrum of flow conditions. Fluids used
were nitrogen gas, oil (Forties and Beryl crude oil – D80, 33o API gravity) and water (salinity
levels of 50 and 100 g/l MgSO4). The sensor spool piece was horizontally mounted on a 4-inch
(102mm) pipe, and the database was obtained from two different locations on the flow loop.
The ability to learn from ‘experience’ is a feature of neural networks. The use of neural
networks allows re-calibration of the measuring system on line through a retraining process
when new information becomes available. Some benefits and capabilities of intelligent
multiphase flow systems include:
Reduction in the physical size of installations.
Sensor fusion by merging the operating envelopes of different sensors employed
provided even better results.
Monitoring of flow conditions, not just flow rate but also composition of components.
Using conventional sensors within the system will present the industry with a much
lower cost multiphase meter, and better reliability.
Comment [HS1]: I think this word
should be measured to make the sentence
read correctly
Estimating the concentration of physico chemical parameters in hydroelectric power plant reservoir
The United Nations Educational, Scientific and Cultural Organization (UNESCO) defines
the amazon region and adjacent areas, such as the Pantanal, as world heritage territories, since
they possess unique flora and fauna and great biodiversity. Unfortunately, these regions have
increasingly been suffering from anthropogenic impacts. One of the main anthropogenic impacts
in the last decades has been the construction of hydroelectric power plants.
As a result, dramatic altering of these ecosystems has been observed, including changes in
water levels, decreased oxygenation and loss of downstream organic matter, with consequent
intense land use and population influxes after the filling and operation of these reservoirs. This,
in turn, leads to extreme loss of biodiversity in these areas, due to the large-scale deforestation.
The fishing industry in place before construction of dams and reservoirs, for example, has become
much more intense, attracting large populations in search of work, employment and income.
Environmental monitoring is fundamental for reservoir management, and several studies
around the world have been performed in order to evaluate the water quality of these ecosystems.
The Brazilian Amazon, in particular, goes through well defined annual hydrological cycles, which
are very importante since their study aids in monitoring anthropogenic environmental impacts
and can lead to policy and decision making with regard to environmental management of this
area. The water quality of amazon reservoirs is greatly influenced by this defined hydrological
cycle, which, in turn, causes variations of microbiological, physical and chemical characteristics.
Eutrophication, one of the main processes leading to water deterioration in lentic environments,
is mostly caused by anthropogenic activities, such as the releases of industrial and domestic
effluents into water bodies.
Physico-chemical water parameters typically related to eutrophication are, among others,
chlorophyll-a levels, transparency and total suspended solids, which can, thus, be used to assess
the eutrophic state of water bodies.
Usually, these parameters must be investigated by going out to the field and manually
measuring water transparency with the use of a Secchi disk, and taking water samples to the
laboratory in order to obtain chlorophyll-a and total suspended solid concentrations. These
processes are time- consuming and require trained personnel. However, we have proposed other
techniques to environmental monitoring studies which do not require fieldwork, such as remote
sensing and computational intelligence.
Simulations in different reservoirs were performed to determine a relationship between these
physico-chemical parameters and the spectral response. Based on the in situ measurements,
empirical models were established to relate the reflectance of the reservoir measured by the
satellites. The images were calibrated and corrected atmospherically.
Statistical analysis using error estimation was used to evaluate the most accurate methodology.
The Neural Networks were trained by hydrological cycle, and were useful to estimate the physicalchemical
parameters of the water from the reflectance of visible bands and NIR of satellite images,
with better results for the period with few clouds in the regions analyzed.
The present study shows the application of wavelet neural network to estimate water quality
parameters using concentration of the water samples collected in the Amazon reservoir and Cefni
reservoir, UK. Sattelite imagens from Landsats and Sentinel-2 were used to train the ANN by
hydrological cycle.
The trained ANNs demonstrated good results between observed and estimated after Atmospheric
corrections in satellites images. The ANNs showed in the results are useful to estimate
these concentrations using remote sensing and wavelet transform for image processing.
Therefore, the techniques proposed and applied in the present study are noteworthy since
they can aid in evaluating important physico-chemical parameters, which, in turn, allows for identification of possible anthropogenic impacts, being relevant in environmental management
and policy decision-making processes.
The tests results showed that the predicted values have good accurate. Improving efficiency
to monitor water quality parameters and confirm the reliability and accuracy of the approaches
proposed for monitoring water reservoirs.
This thesis contributes to the evaluation of the accuracy of different methods in the estimation
of physical-chemical parameters, from satellite images and artificial neural networks. For future
work, the accuracy of the results can be improved by adding more satellite images and testing
new neural networks with applications in new water reservoirs
A review of ultrasonic sensing and machine learning methods to monitor industrial processes
Supervised machine learning techniques are increasingly being combined with ultrasonic sensor measurements owing to their strong performance. These techniques also offer advantages over calibration procedures of more complex fitting, improved generalisation, reduced development time, ability for continuous retraining, and the correlation of sensor data to important process information. However, their implementation requires expertise to extract and select appropriate features from the sensor measurements as model inputs, select the type of machine learning algorithm to use, and find a suitable set of model hyperparameters. The aim of this article is to facilitate implementation of machine learning techniques in combination with ultrasonic measurements for in-line and on-line monitoring of industrial processes and other similar applications. The article first reviews the use of ultrasonic sensors for monitoring processes, before reviewing the combination of ultrasonic measurements and machine learning. We include literature from other sectors such as structural health monitoring. This review covers feature extraction, feature selection, algorithm choice, hyperparameter selection, data augmentation, domain adaptation, semi-supervised learning and machine learning interpretability. Finally, recommendations for applying machine learning to the reviewed processes are made
Mining Safety and Sustainability I
Safety and sustainability are becoming ever bigger challenges for the mining industry with the increasing depth of mining. It is of great significance to reduce the disaster risk of mining accidents, enhance the safety of mining operations, and improve the efficiency and sustainability of development of mineral resource. This book provides a platform to present new research and recent advances in the safety and sustainability of mining. More specifically, Mining Safety and Sustainability presents recent theoretical and experimental studies with a focus on safety mining, green mining, intelligent mining and mines, sustainable development, risk management of mines, ecological restoration of mines, mining methods and technologies, and damage monitoring and prediction. It will be further helpful to provide theoretical support and technical support for guiding the normative, green, safe, and sustainable development of the mining industry
Combining Synthesis of Cardiorespiratory Signals and Artifacts with Deep Learning for Robust Vital Sign Estimation
Healthcare has been remarkably morphing on the account of Big Data. As Machine Learning
(ML) consolidates its place in simpler clinical chores, more complex Deep Learning (DL) algorithms
have struggled to keep up, despite their superior capabilities. This is mainly attributed
to the need for large amounts of data for training, which the scientific community is unable to
satisfy.
The number of promising DL algorithms is considerable, although solutions directly targeting
the shortage of data lack. Currently, dynamical generative models are the best bet, but focus on
single, classical modalities and tend to complicate significantly with the amount of physiological
effects they can simulate.
This thesis aims at providing and validating a framework, specifically addressing the data
deficit in the scope of cardiorespiratory signals. Firstly, a multimodal statistical synthesizer was
designed to generate large, annotated artificial signals. By expressing data through coefficients of
pre-defined, fitted functions and describing their dependence with Gaussian copulas, inter- and
intra-modality associations were learned. Thereafter, new coefficients are sampled to generate
artificial, multimodal signals with the original physiological dynamics. Moreover, normal and
pathological beats along with artifacts were included by employing Markov models. Secondly,
a convolutional neural network (CNN) was conceived with a novel sensor-fusion architecture
and trained with synthesized data under real-world experimental conditions to evaluate how its
performance is affected.
Both the synthesizer and the CNN not only performed at state of the art level but also innovated
with multiple types of generated data and detection error improvements, respectively.
Cardiorespiratory data augmentation corrected performance drops when not enough data is available,
enhanced the CNN’s ability to perform on noisy signals and to carry out new tasks when
introduced to, otherwise unavailable, types of data. Ultimately, the framework was successfully
validated showing potential to leverage future DL research on Cardiology into clinical standards
Multiphase flow measurement and data analytic based on multi-modal sensors
Accurate multiphase flow measurement is crucial in the energy industry. Over
the past decades, separation of the multiphase flow into single-phase flows has
been a standard method for measuring multiphase flowrate. However, in-situ, non-invasive, and real-time imaging and measuring the key parameters of multiphase
flows remain a long-standing challenge. To tackle the challenge, this thesis first
explores the feasibility of performing time-difference and frequency-difference imaging
of multiphase flows with complex-valued electrical capacitance tomography (CVECT).
The multiple measurement vector (MMV) model-based CVECT imaging algorithm
is proposed to reconstruct conductivity and permittivity distribution simultaneously,
and the alternating direction method of multipliers (ADMM) is applied to solve
the multi-frequency image reconstruction problem. The proposed multiphase flow
imaging approach is verified and benchmarked with widely adopted tomographic
image reconstruction algorithms. Another focus of this thesis is multiphase flowrate
estimation based on low-cost, multi-modal sensors. Machine learning (ML) has
recently emerged as a powerful tool to deal with time series sensing data from multi-modal sensors. This thesis investigates three prevailing machine learning methods,
i.e., deep neural network (DNN), support vector machine (SVM), and convolutional
neural network (CNN), to estimate the flowrate of oil/gas/water three-phase flows
based on the Venturi tube. The improvement of CNN with the combination of long-short term memory machine (LSTM) is made and a temporal convolution network
(TCN) model is introduced to analyse the collected time series sensing data from the
Venturi tube installed in a pilot-scale multiphase flow facility. Furthermore, a multi-modal approach for multiphase flowrate measurement is developed by combining
the Venturi tube and a dual-plane ECT sensor. An improved TCN model is built
to predict the multiphase flowrate with various data pre-processing methods. The
results provide guidance on data pre-processing methods for multiphase flowrate
measurement and suggest that the proposed combination of low-cost flow sensing
techniques and machine learning can effectively translate the time series sensing
data to achieve satisfactory flowrate measurement under various flow conditions
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